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Chapter 4

Chapter 4 – Potentially VulnerableSpecies: Animals

The last word in ignorance is the man who says of an animal orplant: ‘What good is it?’ If the land mechanism as a whole is good,then every part is good, whether we understand it or not. If thebiota, in the course of aeons, has built something we like but do notunderstand, then who but a fool would discard seemingly uselessparts? To keep every cog and wheel is the first precaution of intelligenttinkering.

—Aldo Leopold (1953)

Key Questions• Which species are rare or at risk in

the coastal mountains and foothillsof southern California?

• What is known about the status anddistribution of each?

• What factors threaten theircontinued persistence?

• What is the potential for conservingon existing public lands?

• To what extent are they vulnerable tocurrent agents of change?

In chapters 4 and 5 we examine the cur-rent status and trends of species that, for avariety of reasons, may be vulnerable to ex-tinction in the assessment area. Here in chapter4 we address animals, and plants are consid-ered in chapter 5. Taxa were selected usingvarious “species of concern” lists that state andfederal wildlife agencies and private conserva-tion organizations have developed (fig. 4.1).Also identified were species that are consid-ered common elsewhere but are rare orpotentially at risk within the assessment area.Each identified species possesses one or moreof the following traits: (1) occurs in only afew limited areas, (2) is particularly vulner-able to prevailing landscape changes, (3) has asmall population size, (4) has large area re-

quirements, or (5) there is a great deal of un-certainty about its distribution and abundance.

Using the fine-filter screening criteria, weidentified 181 animals occurring within ornear the assessment area which warrant indi-vidual consideration (fig 4.2). Thirty-one ofthese species are officially listed as threatenedor endangered (table 4.1), and thus legallyprotected under the federal Endangered Spe-cies Act. The remaining 150 species couldbecome candidates for federal listing in thefuture if measures are not taken to assure theirconservation. Our primary objective was touse the available data on these species to

Figure 4.1. The fine-filter criteria used toidentify rare or at-risk species. These speciesare addressed individually in this chapter.

• Threatened, Endangered, and ProposedSpecies (federal and state lists)

• A former USFWS Candidate (C1 and C2)Species

• A Forest Service, Region 5 SensitiveSpecies

• A California Species of Special Concern• A Riparian Obligate Species of Concern

(as defined by California Partners inFlight)

• A species determined to have viabilityconcerns at a local level

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Evaluating Status andConservation Potential

The potential for conservation, and theactions needed to conserve, vary considerablydepending on the individual characteristics ofeach species. To evaluate those characteristics,we compiled information on species-habitatassociations and used GIS coverages to pre-dict habitat suitability across the landscape.Databases of habitat and life history infor-mation were compiled for both animals andplants. In addition, the locations of current

assess their current status and vulnerabilitywithin the assessment area, and identify theirconservation needs. This information can thenbe used when developing managementpriorities.

Several species that occurred within theassessment area as recently as 50 to 150 yearsago are not addressed here because they areknown to have been extirpated. These are theCalifornia grizzly bear (Ursus arctoscalifornicus), gray wolf (Canis lupus fuscus),long-eared kit fox (Vulpes macrotis macrotis),and pronghorn antelope (Antilocapraamericana) (Williams 1986).

Determinations were made after analyz-ing available information on life historycharacteristics, degree of rarity or endemism,regional context, response to land use, extantpopulation size and trend, and other variablesas necessary. A matrix of species-specific char-acteristics was created to assist in this process.The categories and their associated criteria aredescribed in table 4.2. A complete listing ofall species by conservation category is locatedin appendix A. The findings from our speciesevaluations are summarized in the followingsections.

and historic observations of these species werecompiled and stored in a GIS database.

For vertebrate animals, we utilized infor-mation on distribution and habitat relation-ships from the CWHR database, but withmodifications to tailor it more specifically tothe habitats and geographic subregions insouthern California. Following the ideas ofHansen and Urban (1992), we also collectedavailable information on territory size, patchsize requirements, resilience to stressors, feed-ing strategy, and nest height. This type of lifehistory information was not available for manyspecies.

There are some clear differences in thedistribution of various taxa that have impor-tant ramifications for conservation andmanagement. For example, many rare plantsand invertebrates are narrowly endemic to aparticular area (e.g., restricted to a singlemountain range or watershed), while most rarevertebrates tend to be more widespread (fig.4.3). Successful conservation strategies formore widespread species generally require ahigher level of coordination and cooperationbetween landowners and jurisdictions.

Borrowing an approach developed by theSouthern Orange County NCCP ScientificAdvisory Committee (Atwood et al. 1996),we evaluated each species and placed it into aconservation category based on criteria that(1) consider its conservation needs, (2) assessthe ability to meet those needs on public landswithin the assessment area, and (3) evaluatethe type of actions needed.

Figure 4.2. The breakdown of rare or at-risk speciesby taxonomic group.

Plants255

Inverts24

Fish 11

Mammals 38

Herps35

Birds72

Invertebrates:Smith’s blue butterfly Euphilotes enoptes smithi Endangered 1976 yQuino checkerspot butterfly Euphydryas editha quino Endangered 1997 y p pLaguna Mountains skipper Pyrgus ruralis lagunae Endangered 1997 yLonghorn fairy shrimp Branchinecta longiantenna Endangered 1994 pVernal pool fairy shrimp Branchinecta lynchi Threatened 1994 p p

Fish:Southern steelhead Oncorhynchus mykiss Endangered 1998 h/p h h yMojave tui chub Gila bicolor mohavensis Endangered 1970 yhyb

Unarmored 3-spined Gasterosteus aculeatus Endangered 1970 y y h stickleback williamsoniTidewater goby Eucyclogobius newberryi Endangered 1994 p

Amphibians:Arroyo toad Bufo californicus Endangered 1994 y y y yCalifornia red-legged frog Rana aurora draytonii Threatened 1996 h/p h/p y y

Reptiles:Desert tortoise Xerobates agassizii Threatened 1980 p pBlunt-nosed leopard lizard Gambelia silus Endangered 1967 p

Birds:California brown pelican Pelecanus occidentalis Endangered 1970 y

californicusWestern snowy plover Charadrius alexandrinus Threatened 1993 p

nivosusMarbled murrelet Brachyramphus marmoratus Threatened 1992 yCalifornia condor Gymnogyps californianus Endangered 1967 h h h/p yBald eagle Haliaeetus leucocephalus Threatened 1978 y y y yAmerican peregrine falcon* Falco peregrinus anatum Endangered 1970 y y y ySouthwestern willow Empidonax traillii extimus Endangered 1995 y y y p flycatcherCalifornia gnatcatcher Polioptila californica californica Threatened 1993 y pLeast Bell’s vireo Vireo bellii pusillus Endangered 1986 y p p y

Mammals:Pacific pocket mouse Perognathus longimembris Endangered 1994 p

pacificusGiant kangaroo rat Dipodomys ingens Endangered 1987 h/pStephens’ kangaroo rat Dipodomys stephensi Endangered 1988 p pSan Bernardino kangaroo rat Dipodomys merriami parvus Endangered 1998 y pSan Joaquin kit fox Vulpes macrotis mutica Endangered 1967 yPeninsular bighorn sheep Ovis canadensis “cremnobates” Endangered 1998 ySouthern sea otter Enhydra lutris nereis Threatened 1977 ySteller sea lion Eumetopias jubatus Threatened 1990 y

Table 4.1. The thirty-one federally listed animal species occurring within or near the assessment area andtheir distribution by national forest (y = occurs, h = historically occurred, p = potential to occur, hyb = hybrid).

Federal YearCommon Name Scientific Name Status Listed

CNF

SBNF

ANF

LPNF

* delisted in 1999 (USFWS 1999)

Figure 4.3. The distribution of rare species varies by type. Invertebrate and plant species tend to be muchmore localized, with over 80 percent occurring on only one national forest (NF) in the assessment area. Rarevertebrates are more widely distributed, with 41 percent occurring on all four national forests.

Minimal Influence: Minimal ability to conserve on public lands within the assessment area

Species whose conservation is affected minimally by management of public lands in the mountains and

foothills. Suitable habitat for these species occurs outside the assessment area (or at least outside of

public lands within the assessment area), but they occur within the area only incidentally or in

insignificant numbers.

Landscape Level: Species best conserved through habitat or landscape-level management

Species that can be conserved through management activities at the habitat or landscape scale. These

species have relatively robust populations and/or have life history characteristics that respond to

habitat-scale conservation. They tend to be predictable occupants of a broad habitat type or structural

stage; thus, species-specific surveys are not crucial in order to conserve. Their persistence can be

relatively accurately inferred in a well-managed, functioning landscape that is within the natural range

of variability.

Site Specific: Species requires site-specific conservation attention

Organisms requiring species-level conservation action (including protection of individual locations) in

order to ensure their persistence in the planning area. Species in this category have one or more of the

following characteristics: extremely small populations, narrow endemism within the landscape, highly

specialized life history requirements, high sensitivity to small changes in habitat, dependence on

intensive conservation activities (e.g., exotic species control). The species in this category require one

or more of the following conservation actions: (1) site-specific protections or habitat enhancements, (2)

reintroductions, (3) additional data collection and research to determine basic needs.

Table 4.2. The categories and criteria used to evaluate each species’ conservation potential and needs onpublic lands within the assessment area.

Invertebrates(n = 156)

2 NFs17%

1 NF83%

Plants(n = 255)

3 NFs4%

2 NFs14%

1 NF82%

Vertebrates(n = 156) 1 NF

30%

3 NFs8%

4 NFs41%

2 NFs21%

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Chapter 4

Species AccountsIn the following sections, organized by

habitat groups, we summarize what is knownabout the 165 potentially vulnerable animalspecies. We focus primarily on informationthat is specific to populations in or near theassessment area. The individual accounts varyconsiderably in length and specificity, reflect-ing the variability of available information.Some species have received a lot of researchattention, while others have been almost en-tirely ignored. Because of the public interestand regulatory requirements associated withlisted T&E species, there tends to be muchmore information about them. For many ofthe nonlisted species, the amount of informa-tion on specific occurrences or even habitatassociations within the assessment area is re-markably small. Thus, we have tried to identifyimportant information needs in the speciesaccounts.

Tables in each section summarize the dis-tribution of each species within the assessmentarea. Also provided are general estimates of(1) how much information exists document-ing locations of the species in the southernCalifornia region, (2) what percentage of thoselocations are on national forest system lands,and (3) how vulnerable the species is to landuses and habitat changes occurring on nationalforest system lands in the assessment area.Population trend information is also shown if

available and the assigned conservation cat-egory, based on criteria in table 4.2, is provided.

The estimates of distributional knowledge,percent of occurrences on national forest sys-tem lands, and overall vulnerability should beregarded as educated guesses based on avail-able information and consultations with localexperts. There is a particularly high level ofuncertainty associated with the estimated per-centage of occurrences that fall on nationalforest system lands. The vulnerability catego-ries were based on sensitivity to the prevailingagents of change described in chapter 3, suchas current fire and stream flow regimes, non-native species, human land use activities, andpollution.

Habitat GeneralistsSeventeen animal species that warrant in-

dividual consideration are best described ashabitat generalists. Key habitat managementissues identified for species in this group in-clude (1) conservation of mesic microhabitatsin arid upland plant communities, (2) protec-tion of raptor cliff-nesting sites during thebreeding season, and (3) protection of aban-doned mine shafts that serve as importanthibernacula and roosting habitat for several batspecies. We conclude that only one of thesespecies, the California condor, is highly vul-nerable to existing agents of change on publiclands within the assessment area (table 4.3).

To structure the evaluation process, weseparated species into groups based on pri-mary habitat associations. The groupings areclearly generalizations and few of the speciesfit perfectly within their assigned habitatgroup. Many species occupy additional habi-tats and others, particularly invertebrates,occur in only a small portion of the definedhabitat association. Still, it is useful to orga-nize species based on general factors that helppredict their occurrence. The groups are definedprimarily by associations with vegetation types,but soil, geology, moisture, and elevation werealso used as habitat indicators.

California legless lizard (Anniella pulchra)Status and Distribution: The legless liz-

ard is a Forest Service Region 5 SensitiveSpecies and a California Species of SpecialConcern. Its geographic range overlaps exten-sively with the assessment area, although it isprimarily found at low elevations. Its reportedelevation range extends from sea level to ap-proximately 5,700 feet in the Sierra Nevadafoothills, but most historic localities along thecentral and southern California coast are be-low 3,500 feet (Jennings and Hayes 1994).Legless lizards are particularly well docu-mented in coastal dune habitats, but thedistribution map in Jennings and Hayes

Habitat GeneralistAnimals of Concern

federal status

(1)Knowledgeof SoCalLocations

(% on NFs)

(5)Conser-vation

Category

(4) Pop.Trend

(3)Vulner-ability

on NFs

(2) areas occupied or estimated # of occurrences if spp. localized

San Bern. NFCleveland NF Angeles NF Los Padres NFSan

DiegoRngs

SanJacMts

SntaAnaMts

SanBernMts

No.SL

Rng

So.SL

Rng

SanGabMts

Cas-taic

Rngs

So.LP

Rngs

Table 4.3. Habitat generalist animals that received individual consideration.Displayed for each species: (1) the level of knowledge about where it occurs in southern California and, inparentheses, the estimated percentage of locations that are on national forest system lands; (2) the mountainsubareas occupied (y = occurs in breeding season, h = historically occurred, p = potentially occurs, t = transient,w = winter visitor)—if the species is localized and data are available, the approximate number of occurrences may bedisplayed; (3) the vulnerability of populations on national forest system lands to existing threat factors; (4)population trends; and (5) the assigned conservation category.

Reptiles

California legless lizard Mod-Low y y y p y y y y y Low Unkn Landscape

(10-40%) level

Coronado skink Mod y y Low Unkn Landscape

(10-50%) level

San Bernardino Mod-Low y y y p p Low Unkn Landscape

ringneck snake (10-40%) level

San Diego Mod-Low y p y Low Unkn Landscape

ringneck snake (10-30%) level

Cliff-Nesting Birds

California condor High h h h h h h/p 16 12 p High Incr Site

endangered (> 70%) specific

Golden eagle High y y y y y y y y y Mod Decl1 Landscape

(30-60%) level

Peregrine falcon Mod y p p p p p p p y Mod Incr2 Site specific

endangered* (< 20%) (nest sites)

Prairie falcon Mod y p y y y y y y y Mod Unkn Landscape

(30-60%) level

Mammals

Yuma myotis bat Mod y y y y y y y y y Low Unkn Landscape

(20-40%) level

Western small-footed Mod y y y y y y y y y Low Unkn Landscape

myotis bat (40-70%) level

Spotted bat Low y p y y y y p Low Unkn Landscape

(?) level

Townsend’s big-eared Mod y y y y y y y y y Mod Unkn Site specific

bat (30-60%) (mine roosts)

Pallid bat Low y y y y y y y y y Low Unkn Landscape

(10-30%) level

Western mastiff bat Mod y y y y y y y p p Low Unkn Landscape

(10-50%) level

California chipmunk Mod y y Low Unkn Landscape

(40-70%) level

Western spotted skunk Low y y y y y y y y y Low Unkn Landscape

(30-70%) level

American badger Low y y y y y y y y y Mod Decl3 Site

(< 20%) specific

1 Declining in San Diego County based on monitoring done by San Diego Golden Eagle Study Group2 Based on rangewide information from Cade et al. 19973 Williams 1986* formally removed from the Endangered Species List in 1999 (USFWS 1999)

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Chapter 4(1994) suggests they probably occur in thelower reaches of all our mountain subareaswith the possible exception of the San Ber-nardino Mountains.

Habitat: The California legless lizard is aburrowing species associated with sandy orloose loamy soils under the sparse vegetationof beaches, chaparral, or pine-oak woodland,or under sycamores, cottonwoods, or oaksgrowing on stream terraces (Jennings andHayes 1994). It also occurs in desert scrubalong the western edge of the Mojave Desertnear Lancaster and in western portions ofAnza-Borrego Desert State Park. Legless liz-ards are often found under surface objects suchas logs, rocks, and leaf litter. Soil moisture isessential for them and legless lizards die if theyare unable to reach a moist substrate (Buryand Balgooyen 1976).

Fisher and Case (1997) describe findinglegless lizards at several locations in the east-ern Santa Ana Mountains (i.e. Indian Canyon,Ortega Highway, and upper Tenaja TruckTrail) under oak woodland, chaparral, andcoastal scrub vegetation in decomposing gran-ite soils. They suggest that the distribution ofthese lizards in foothill and lower montaneareas may be closely tied to decomposing gran-ite soils.

Conservation Considerations: Given thelegless lizard’s habitat requirements, life his-tory characteristics, and relatively broaddistribution, we believe it is not highly vul-nerable to existing agents of change in themountains and foothills. Thus, populations onpublic lands within the assessment area canbe adequately conserved through landscape-scale, habitat-based management. However,given the limited amount of information onthe distribution and abundance of this spe-cies in foothill and lower montane areas, wedo wonder if these upper-elevation habitatsare productive enough to support self-sustain-ing populations. Habitat connections towildland reserves in the coastal and inlandvalleys may be important for this species. Also,Jennings and Hayes (1994) describe problemsassociated with invasive non-native plants incoastal dune habitats. Exotic plants could be

a problem for legless lizards in other habitatstoo, especially if they affect soil moisture.

Coronado skink(Eumeces skiltonianus interparietalis)

Status and Distribution: A subspecies ofwestern skink, the Coronado skink is a Cali-fornia Species of Special Concern. It reportedlyinhabits the coastal plain and PeninsularRanges west of the deserts from approximatelySan Gorgonio Pass southward into Baja Cali-fornia (Jennings and Hayes 1994). However,there are problems with the taxonomy of Pa-cific Coast skinks in general and with themorphological characteristics used to distin-guish the Coronado skink in particular(Jennings and Hayes 1994).

Fisher and Case (1997) report that thecharacteristics used to identify the Coronadosubspecies are ill defined and the main char-acter (shape of the interparietal) is variable andnever occurs in a large proportion of individu-als, even at locations within the range of theproported subspecies. They found Eumecesskiltonianus at study sites near Big Bear in theSan Bernardino Mountains; at the James Re-serve in the San Jacinto Mountains; at PalomarMountain, Otay Mountain, and Japatul in SanDiego County; and at Starr Ranch in the SantaAna Mountains. However, they could not re-liably separate E. s. interparietalis from themore common E. s. skiltonianus based onmorphological characteristics (Fisher and Case1997).

Habitat: The Coronado skink reportedlyoccurs in a variety of plant associations includ-ing coastal sage scrub, chaparral, oakwoodlands, pinyon-juniper woodlands, ripar-ian woodlands, and coniferous forests.However, within these associations it is oftenrestricted to more mesic microhabitats(Jennings and Hayes 1994).

Conservation Considerations: As sug-gested by Jennings and Hayes (1994) andFisher and Case (1997), a review of the sys-tematic status of the Coronado skink relativeto other western skinks is needed to determineif it really warrants subspecies status and, if

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so, to better describe identifying characteris-tics. The Coronado skink has a relatively broaddistribution, and the work of Fisher and Case(1997) suggests it is fairly common in areas ofsuitable habitat. Thus, we believe it can beadequately conserved through landscape-scale,habitat-based management. Jennings andHayes (1994) express concern about the dry-ing up of mesic microhabitats due to humanuse of surface and underground water re-sources and the effect it may have on thisspecies. Management consideration should begiven to identifying and conserving these mi-crohabitats. It appears that trends in skinkabundance can be effectively monitored us-ing pitfall trap arrays (Fisher and Case 1997).

San Bernardino ringneck snake(Diadophis punctatus modestus)

Status and Distribution: The San Bernar-dino ringneck snake is a Forest Service Region5 Sensitive Species. Information on its distri-bution within the assessment area is scant.Most museum specimens are from coastal ba-sins and inland valleys. Blanchard (1942)documents occurrences in Miller Canyon inthe San Gabriel Mountains, Mill Creek andthe upper Santa Ana River (near Lost Creek)in the San Bernardino Mountains, and inTrabuco Canyon in Orange County (poten-tially within the Santa Ana Mountains). Fisherand Case (1997) found ringneck snakes onStarr Ranch at the foot of the Santa Ana Moun-tains but did not identify them to subspecies.

Habitat: Ringneck snakes are found in awide variety of habitats from sea level to 6,400feet (Blanchard 1942). Existing distributionalinformation is spotty, but it appears that thesesnakes are more common at low elevation sites(i.e., below 3,000 feet). Ringneck snakes arenot strongly associated with riparian habitats,but the apparent importance of tree frogs andslender salamanders in their diet (Blanchard1942; Stebbins 1972) suggests they may seekout and require moist microclimates. This isalso suggested by their reported absence fromdesert-side habitats (Blanchard 1942). Ring-

neck snakes are rarely seen on the surface butrather are found under rocks, logs, or leaf litter.

Conservation Considerations: The ring-neck snake’s secretive nature, relatively broaddistribution, and generalized habitat associa-tions suggest it can be conserved throughlandscape-scale, habitat-based management. Itdoes not seem particularly vulnerable to ex-isting change agents on public lands. Mesicmicrohabitats in otherwise arid, upland veg-etation types appear to be important to thisspecies. Management consideration should begiven to identifying and conserving these mi-crohabitats. It would be very difficult tomonitor population trends of ringneck snakesacross a broad region in a reliable manner.

San Diego ringneck snake(Diadophis punctatus similis)

Status and Distribution: The San Diegoringneck snake is a Forest Service Region 5Sensitive Species. Recent information on itsdistribution within the assessment area is scant.Fisher and Case (1997) found ringneck snakesin Hall Canyon in the San Jacinto Mountains,and on Otay Mountain in San Diego Countyand also report them as being widespread atlow-elevation inland valley sites in Riversideand San Diego counties. Other recently re-ported localities in the San Jacinto Mountainsinclude Apple Canyon, upper Hurkey Creek,Idyllwild, Dark Canyon, and Vista GrandeFire Station (D. Freeman, San Jacinto RangerDistrict, unpubl. notes). In San Diego County,they have recently been detected in Pamo Val-ley and Barona Creek (D. Mayer, Merkel &Associates, pers. comm.).

Blanchard (1942) documents occurrencesin Strawberry Canyon in the San JacintoMountains and in Pine Valley, Santa Ysabel,Warner Springs, Witch Creek, and Wynola inthe mountains of San Diego County. Unpub-lished maps based on Laurence Klauber’s workfrom the 1920s through the 1940s show theSan Diego localities reported by Blanchard andalso additional ones within the assessment areaat Pine Valley, Laguna Mountain, CuyamacaLake, Boulder Creek, Pine Hills, and the southside of Palomar Mountain.

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Chapter 4Habitat: Similar to that described for the

San Bernardino ringneck snake. The highestrecorded elevation is 5,500 feet. Blanchard(1942) reports that most specimens of thissubspecies came from coastal areas, withsmaller numbers from inland valleys and foot-hills, and only a few from the mountains. Thispattern is also reflected in the maps ofKlauber’s collections. Fisher and Case (1997)report that ringneck snakes were widespreadin coastal sage scrub and oak woodland habi-tats at coastal sites in San Diego and Orangecounties and at inland valley sites in RiversideCounty. Holland and Goodman (1998) foundthis snake on Camp Pendleton in coastal sagescrub, chaparral, oak woodland, grassland, andriparian areas.

Conservation Considerations: Same asthose described for the San Bernardino ring-neck snake.

California condor(Gymnogyps californianus)

Status and Distribution: The Californiacondor was federally listed as an endangeredspecies in 1967. In 1987, after years of steadypopulation declines, the last nine wild con-dors were captured on the Los Padres NationalForest and brought into captivity. Since thattime successful captive breeding programs havebeen ongoing at the Los Angeles Zoo and SanDiego Wild Animal Park (AZA 1995).

In January 1992, the first two Californiacondors were reintroduced into the Los Pa-dres National Forest’s Sespe Condor Sanctuary,along with two Andean condors. A total ofthirteen California condors were released atthe Sespe Sanctuary from 1992 to 1994. Fiveof these died, four from collisions with powerlines and one from ingesting ethylene glycol,a poisonous ingredient of antifreeze (AZA1995). The remaining eight were recapturedin March 1995 because of their tendency touse powerlines poles for day perches and over-night roosts.

Since that time, negative conditioning hasbeen used prior to release to train the condorsto avoid powerlines. Alternative release sites,in more remote locations, have also been used.

Release sites on the Los Padres National For-est include the Sierra Madre Mountains andthe Castle Crags area (Fig. 4.4) (AZA 1995).These actions have improved the success ofsubsequent releases. As of February 1999, therewere reportedly 28 wild condors in the vicin-ity of the Los Padres National Forest releasesites (CDFG 1999). Another 22 condors arein the wild on the Vermillion Cliffs of Ari-zona and 97 remain in captivity at three dif-ferent breeding facilities, for a total popula-tion of 147 birds (CDFG 1999).

Habitat: Condors generally nest on cliffs,although they have been observed using cavi-ties in large redwood trees (Jurek 1997). Theyare carrion feeders and often travel long dis-tances in search of large dead animals such asdeer, antelope, cattle, and sheep.

Conservation Considerations: Factorsthat led to the condor’s century-long declineinclude illegal collection of adults and theireggs, poisoning from substances put out byranchers to eradicate livestock predators, poi-soning from ingesting lead fragments frombullets embedded in animal carcasses the con-dors feed on, and collisions with structuressuch as power lines. In addition, the roads,cities, housing tracts, and weekend mountainretreats of modern civilization have replacedmuch of the open country condors need tofind food. Their slow rate of reproduction andyears spent reaching breeding maturity un-doubtedly make the condor population as awhole more vulnerable to these threats.

Keys to the success of the recovery pro-gram include successful breeding in the wildand maintenance of an ample food supply. Thefirst nesting of released condors cannot be ex-pected for at least three to five more years(sometime between 2000 and 2010) (Jurek1997). Currently, supplemental food is hauledin for the wild birds. It remains to be seen ifthe natural supply of large carrion is sufficientto support a stable condor population.

Golden eagle (Aquila chrysaetos)Status and Distribution: The golden eagle

is a California Species of Special Concern. It

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Figure 4.4. Areas currently occupied by California condors on the Los Padres National Forest.

is uncommon, but widely distributed through-out the assessment area, particularly in foothill,lower montane, and desert-montane habitats.Monitoring of historic territories by the SanDiego Golden Eagle Study Group has docu-mented a substantial decline in the San DiegoCounty population (D. Bittner and J. Oakley,pers. comm.). Drops in territory occupancyare most apparent in the coastal foothills wherethere is rapid urban growth.

Habitat: Golden eagles nest primarily oncliffs and hunt for rabbits and other smallmammals in nearby open habitats such asgrasslands, oak savannas, and open shrublands.

Conservation Considerations: Develop-ments on private lands that encroach on key

foraging areas are a problem for golden eagles,particularly in the southern half of the assess-ment area. There appears to be ample nestinghabitat on public land, but in many places thehighest quality foraging areas are on privateland. Increased recreational activity in the vi-cinity of cliff nests, particularly rock climb-ing, is also a problem in some areas and cancause eagles to abandon a site. Managementconsideration should be given to identifyingand protecting active nest sites during thebreeding season.

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Chapter 4American peregrine falcon(Falco peregrinus anatum)

Status and Distribution: The peregrinefalcon was removed from the Endangered Spe-cies List in August 1999. (USFWS 1999). It israre but widely distributed across southern andcentral California, usually near the coast or inother areas where migrant waterfowl or shore-birds are concentrated (e.g., inland reservoirs)(Garrett and Dunn 1981). Peregrine falcons aremore common in northern portions of the as-sessment area that are relatively close to coastalwetlands (i.e., the northern and southern SantaLucia Ranges and the Santa Ynez Mountains).

Widespread and indiscriminate use ofDDT in the middle of the century caused adrastic decline in U.S. peregrine populations.The pesticide, which accumulates in theaquatic food chain, causes a thinning of per-egrine egg shells which lowers reproductivesuccess. Bans on the use of DDT in the 1970sand a major reintroduction campaign led bythe Peregrine Fund have resulted in an im-pressive increase in the distribution andabundance of this bird over the last twentyyears (Cade et al. 1997). The population in-crease has been substantial enough to warrantthe peregrine’s delisting (Mesta et al. 1995; Cadeet al. 1997), although this decision is controver-sial (Pagel et al. 1996; Pagel and Bell 1997).

In the 1980s, a number of peregrine rein-troductions were attempted on the southernCalifornia national forests. Most of these birdsdid not remain in the vicinity of release sites.

Habitat: Peregrine falcons nest high oncliffs, usually near water. Much of the assess-ment area is not high-quality habitat for thisspecies because of the lack of water bodies thatconcentrate its preferred prey.

Conservation Considerations: Protectionof cliff nesting sites from human disturbanceis an important conservation measure for per-egrine falcons.

Prairie falcon (Falco mexicanus)Status and Distribution: The prairie fal-

con is a California Species of Special Concern.It is uncommon but widely distributed in theassessment area. Like the golden eagle, it has

declined in the coastal foothills, probably dueto the loss of foraging habitat (Garrett andDunn 1981).

The prairie falcon’s diet of nonaquaticbirds helped it escape the widespread, DDT-induced declines experienced by the peregrinefalcon. However, localized occurrences of eggthinning in prairie falcons have been reported.

Habitat: Prairie falcons nest on cliffs, gen-erally in arid open areas. Desert scrub andgrasslands are preferred foraging habitats(Garrett and Dunn 1981).

Conservation Considerations: Same asthose described for the golden eagle and per-egrine falcon.

Yuma myotis bat (Myotis yumanensis)Status and Distribution: The Yuma

myotis bat is currently a California Species ofSpecial Concern, although it may soon be re-moved based on a recent status review (P.Collins, Santa Barbara Nat. History Museum,pers. comm.). In bat surveys conducted by theForest Service from 1996 to 1998, Yumamyotis was detected at eighteen of seventy-sixsites surveyed (Simons et al. in prep.). It wasobserved at three or more locations on eachof the four national forests. Yuma myotis wasfound at elevations ranging from 1,400 to7,700 feet, but was most commonly detectedat sites below 5,000 feet (thirteen of the eigh-teen sites).

Habitat: Yuma myotis occurs in a varietyof habitats including riparian, arid scrublands,deserts, and forests (Bogan et al. 1998a). It isusually associated with permanent sources ofwater, typically rivers and streams, where itdoes most of its foraging. Yuma myotis roostsin bridges, buildings, cliff crevices, caves,mines, and trees (Bogan et al. 1998a).

Conservation Considerations: The Yumamyotis bat appears to be well represented onpublic lands in the assessment area, particu-larly at elevations below 5,000 feet on bothcoastal and desert slopes. The ability of thisspecies to utilize a wide range of roost typesreduces its vulnerability. Identification andprotection of maturity colony sites (e.g., in

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caves, mines, or structures) is important to theconservation of this species.

Western small-footed myotis bat(Myotis ciliolabrum)

Status and Distribution: The small-footedmyotis bat is a former C2 candidate species.It was detected at twenty-four of seventy-sixsites surveyed from 1996 to 1998, at eleva-tions ranging from 3,800 to 7,800 feet(Simons et al. in prep.). It was the fourth mostcommonly detected bat species in that surveyand was observed at four or more locationson each of the four national forests.

Habitat: The small-footed myotis is saidto occur in deserts, chaparral, riparian zones,and coniferous forest, and, most commonly,in pinyon-juniper forests (Bogan et al. 1998b).Local surveys found this species most fre-quently in montane conifer forests and desertmontane habitats (Simons et al. in prep.). Thisbat utilizes a variety of roost types.

Conservation Considerations: The west-ern small-footed myotis bat appears to be wellrepresented on public lands in the assessmentarea and its habitat requirements indicate rela-tively low vulnerability to existing agents ofchange. The ability of this species to use a va-riety of roost types reduces its vulnerability.Identification and protection of maturitycolony sites (e.g., in caves, mines, or struc-tures) is important to the conservation of thisspecies.

Spotted bat (Euderma maculatum)Status and Distribution: The spotted bat

is a California Species of Special Concern.There is little current information on its dis-tribution in the assessment area. It wasdetected at only two of seventy-six sites sur-veyed from 1996 to 1998 (on PalomarMountain and in the Sierra Madre Moun-tains), but it is not a species that is often caughtin mist nets (Simons et al. in prep.).

Habitat: Spotted bats forage in a widevariety of habitats but roost strictly in cliffs,which may limit their distribution (Luce1998).

Conservation Considerations: More in-formation is needed on the distribution andabundance of spotted bats within the assess-ment area. Their habit of roosting in cliffsreduces vulnerability to land use activities.

Townsend’s big-eared bat(Corynorhinus townsendii)

Status and Distribution: The Townsend’sbig-eared bat is a Forest Service Region 5 Sen-sitive Species and a California Species ofSpecial Concern. It was detected at six of sev-enty-six sites surveyed from 1996 to 1998 inthe mountains and foothills of southern Cali-fornia (one site on San Bernardino NationalForest and five sites on Cleveland NationalForest) (Simons et al. in prep.). More impor-tantly, it was found at fourteen abandonedmine locations in the northeastern San Ber-nardino Mountains, with fifty-five individualsobserved in one mine (Simons et al. in prep.).It has also been documented in several aban-doned mines in the Laguna Mountains.

Habitat: The distribution of this speciesis strongly correlated with the availability ofcaves and cave-like roosting habitat, withpopulation centers occurring in areas domi-nated by exposed, cavity forming rock and/orhistoric mining areas (Sherwin 1998a). Aban-doned mines are particularly important inareas where there are not well developed caves.

Conservation Considerations: TheTownsend’s big-eared bat’s dependence onabandoned mines for roosting makes it mod-erately vulnerable to ongoing activities. Minevandalism and over-utilization of these sitesare problems in a number of areas. Identifica-tion and protection of significant roost sites iskey to the conservation of this species. Addi-tional surveys are needed to identify roost sites.Several important roost sites have recently beenidentified and protected (by installing bat gatesacross mine entrances) in the San BernardinoMountains (Lisa Underwood, MountaintopDistrict, pers. comm.).

Pallid bat (Antrozous pallidus)Status and Distribution: The pallid bat is

a Forest Service Region 5 Sensitive Species and

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Chapter 4a California Species of Special Concern. It wasdetected at seven of seventy-six sites surveyedfrom 1996 to 1998 in the mountains and foot-hills of southern California (four sites on LosPadres National Forest, three sites on AngelesNational Forest), at elevations ranging from1,100 to 6,600 feet (Simons et al. in prep.). Itwas not detected in abandoned mine surveysin the northeastern San Bernardino Mountains(Simons et al. in prep.).

Habitat: Pallid bats roost in rock crevices,tree hollows, mines, caves, and a variety ofman-made structures (Sherwin 1998b). Lo-cal data suggest that this species may be mostcommon at elevations below 6,000 feet onboth coastal and desert sides (Simons et al. inprep.).

Conservation Considerations: It is diffi-cult to determine how widely distributed orabundant pallid bats are in the assessment areaand more information is needed. Their abil-ity to roost in a wide variety of sites may helpreduce their vulnerability to human activities.

Western mastiff bat (Eumops perotis)Status and Distribution: The western

mastiff bat is a California Species of SpecialConcern. It was detected at twenty-five of sev-enty-six sites surveyed from 1996 to 1998 inthe mountains and foothills of southern Cali-fornia (Simons et al. in prep.). It was the thirdmost commonly detected bat species in thatsurvey and was found on all four national for-ests, in a variety of habitats, and across a broadelevation range (1,100 to 7,600 feet).

Habitat: The mastiff bat is primarily acliff-dwelling species, where maternity colo-nies of thirty to several hundred (typicallyfewer than one hundred) roost generally un-der exfoliating rock slabs (e.g., granite, sand-stone, or columnar basalt) (Pierson 1998). Itcan also be found in similar crevices in largeboulders and buildings. Mastiff bats are foundin a wide variety of habitats, but the species’distribution may be geomorphically deter-mined, occurring primarily where there aresignificant rock features offering suitable roost-ing habitat (Pierson and Rainey 1996; Pierson1998).

Conservation Considerations: The west-ern mastiff bat appears to be widespread inthe assessment area, although its abundanceis unknown. The habitat requirements of thisspecies indicate relatively low vulnerability toexisting agents of change on public lands.Management attention should be given toconserving cliff and rock habitats that provideimportant roost sites. More complete infor-mation is needed on the distribution andabundance of this species in the assessmentarea.

California chipmunk(Tamias obscurus davisi)

Status and Distribution: The Californiachipmunk is not considered to be rare, butwe include it as a local species of concern be-cause its distribution is small and largely withinthe assessment area (Callahan 1977; Zeiner etal. 1990). The subspecies T. o. davisi is knownonly from the San Bernardino, Little San Ber-nardino, Eagle, San Jacinto and Santa Rosamountains of southern California (fig. 4.5)(Callahan 1977). It is reportedly common ondesert-facing slopes of the eastern San Bernar-dino Mountains eastward through the desertranges of Joshua Tree National Monument andin montane conifer habitats in the San Jacintoand Santa Rosa mountains.

Habitat: North of San Gorgonio Pass, T.o. davisi is largely restricted to rocky areas inpinyon-juniper woodland below about 6,700feet. It is replaced at higher elevations by theclosely related Merriam’s chipmunk (Tamiasmerriami). South of San Gorgonio Pass, thespecies are distributed in an opposite pattern:The California chipmunk replaces theMerriam’s chipmunk in plant communitieshigher than pinyon-juniper woodlands andoccurs at elevations up to 8,700 feet (Callahan1977).

Conservation Considerations: It would behelpful to have some current information onthe status of this narrowly distributed species.However, most of the California chipmunk’srange is on public land and its habitat require-ments generally indicate low vulnerability toexisting agents of change.

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Figure 4.5. The known distribution of the California chipmunk.

Western spotted skunk (Spilogale gracilis)Status and Distribution: The spotted

skunk is not on any concern lists and it is be-lieved to be relatively widespread (P. Collins,Santa Barbara Nat. Hist. Museum, pers.comm.). We include it as a local viability con-cern because there is essentially no recent,documented information on its distributionor status in the assessment area.

Habitat: Vaughan (1954) found spottedskunks in rocky canyons on the coastal sideof the San Gabriel Mountains. He thoughtthey also probably occurred in desert slopecanyons. Grinnell et al. (1937) report anelevational range for spotted skunks in south-

ern California of near sea level to at least 4,500feet.

Conservation Considerations: Some cur-rent information is needed on the distributionand abundance of this species on public landswithin the assessment area.

American badger (Taxidea taxus)Status and Distribution: The badger is a

California Species of Special Concern. Its geo-graphic range is large and takes in the entireassessment area, but its local distribution isspotty and not well documented. Badgers canoccur at high elevations in meadows near tim-berline, but we could find little informationdocumenting occurrences at high elevations

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Chapter 4in the southern California mountains. Distri-butional records in Williams (1986) indicatethe presence of badgers on Mount Pinos, butthey are not reported from high meadows inthe San Bernardino and San Jacinto moun-tains or the large mid-elevation meadows onPalomar and Laguna mountains.

Documented localities from the San Ber-nardino and San Jacinto mountains are largelyfrom desert montane areas (e.g., Highway 243south of Banning, Coxey Creek, Burnt Flats,Redonda Ridge, Lone Pine Canyon) and theCajon Wash area (D. Freeman, San Bernar-dino NF, unpubl. notes). A similar pattern wasreported by Vaughan (1954) for the SanGabriel Mountains, with badger sign beingmost common in Joshua tree woodlands andpinyon-juniper associations on the desertslope.

Localities in the San Diego County moun-tains are mainly from valleys in the coastalfoothills (e.g., Ramona, Pamo Valley, SantaYsabel, Witch Creek, and Sweetwater Reser-voir) (Bond 1977). Most of these areas are onprivate land.

Habitat: Badgers can occur in a wide va-riety of arid open habitats but are mostcommonly associated with grasslands, savan-nas, mountain meadows, and openings indesert scrub. The principal requirements seemto be sufficient food (burrowing rodents), fri-able soils, and relatively open, uncultivatedground (Williams 1986). They seem to occurprimarily in areas of low to moderate slope.

Conservation Considerations: Currentinformation is needed on the distribution andabundance of this species on public landswithin the assessment area, particularly in themountain subareas where historic localities aremainly on private lands (e.g., San Diego rangesand Santa Lucia Ranges). The presence of thisspecies can often be determined by sign ofdiggings and burrows.

Animals of Aquatic, Aquatic/Upland, Riparian, and LakeHabitats

Aquatic and riparian habitats are impor-tant to a lot of species and they are of limited

extent in arid southern California. Therefore,it is not surprising that thirty-nine rare or po-tentially at risk animals are closely associatedwith these habitat types. To address all of thesespecies, we have further subdivided this groupinto six categories: fish (fully aquatic), aquatic/upland amphibians and reptiles, riparian birds,mammals, invertebrates, and lake-associatedspecies.

Fish

There are few native fish in southern Cali-fornia streams and essentially all of them arerare and at risk. Nine native fish species areconsidered individually below (table 4.4).

Pacific lamprey (Lampetra tridentata)Status and Distribution: This anadro-

mous lamprey is not on any official concernlists, but we include it as a local viability con-cern species because its habitat requirementsare similar to the steelhead (Swift et al. 1993)and it faces many of the same threat factors.Lampreys still maintain runs in several creeksalong the coast in Monterey and San LuisObsipo counties, in parts of the Santa Mariaand Santa Ynez rivers, parts of the VenturaRiver, and the Sespe Creek portion of the SantaClara River drainage (Swift et al. 1993).

Habitat: Similar to that described for thesouthern steelhead.

Conservation Considerations: See south-ern steelhead account.

Southern steelhead(Oncorhynchus mykiss)

Status and Distribution: West coast steel-head populations have been divided intofifteen evolutionarily significant units (ESUs)based on natural geographic boundaries thatfoster genetic isolation (NMFS 1997a). EachESU is treated as a distinct population by theNational Marine Fisheries Service (NMFS) fordeterminations on the need for listing asthreatened or endangered. Our assessment areaspans two ESUs: the south-central Californiacoast ESU, which has been listed as threat-ened, and the southern California coast ESU,

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Fish of Concernfederal status

(1)Knowledge

of SoCalLocations

(% on NFs)

(5)Conser-vation

Category

(4) Pop.Trend

(3)Vulner-ability

on NFs

(2) areas occupied or estimated # of occurrences if spp. localized

San Bern. NFCleveland NF Angeles NF Los Padres NFSan

DiegoRngs

SanJacMts

SntaAnaMts

SanBernMts

No.SL

Rng

So.SL

Rng

SanGabMts

Cas-taic

Rngs

So.LP

Rngs

Pacific lamprey Mod h/p h h h 3-4 1 5 Mod Unkn Landscape(< 20%) level

Southern steelhead High h h/p h h 7-10 ~6 ~11 High Decl1 Siteendangered/threatened (25-50%) specific

Mojave tui chub High 1Hyb Mod Unkn Site endangered (50-75%) specific

Arroyo chub High 2 3 2 2 7-8 5 Int 9 Int 3 Int Mod Unkn Landscape(40-60%) level

Santa Ana speckled Mod 2 1-2 6-7 ~9 h 2SL 2 SL Mod Unkn Landscape dace (40-60%) level

Santa Ana sucker High h h h/p 4-5 2Int 2 Int High Decl2 Site(50-75%) specific

Unarmored three- High 2Sh 1 2 High Site spine stickleback (40-60%) specific endangered

Partially armored Mod h/p y y y Int y Int p y y y Mod Unkn Landscape threespine stickleback (40-70%} level

Tidewater goby High p None Decl MinimaIInfluence

which has been listed as endangered (NMFS1997b).

The south-central coast ESU encompassesstreams that drain the northern and southernSanta Lucia Ranges down to (but not includ-ing) the Santa Maria River in San Luis ObispoCounty. The primary rivers supporting steel-head runs in this ESU are the Pajaro, Salinas,

Table 4.4. Rare or potentially at risk fish that are native to southern California.Displayed for each species: (1) the level of knowledge about where it occurs in southern California and, inparentheses, the estimated percentage of locations that are on national forest system lands; (2) the mountainsubareas occupied (y = occurs in breeding season, h = historically occurred, p = potentially occurs, t = transient,w = winter visitor)—if the species is localized and data are available, the approximate number of occurrences may bedisplayed; (3) the vulnerability of populations on national forest system lands to existing threat factors; (4)population trends; and (5) the assigned conservation category.

1 Source: NMFS (1997b).2 Source: Swift et al. (1993)Hyb Mojave tui chubs in San Bernardino Mountains (Deep Creek) have hybridized with arroyo chubs.Int Introduced populations, not part of historic range.SL San Luis Obispo speckled dace may be a distinct subspecies (Swift et al. 1993).Sh Unarmored 3-spine stickleback in San Bernardino Mountains is genetically distinct Shay Creek form (Haglund and Buth 1988).

Carmel, Little Sur and Big Sur rivers. How-ever, an additional fifteen to twenty smallerstreams along the Monterey and San LuisObispo coast also support steelhead. Streamsspecified in the final rule on this ESU thatoccur at least partially on national forest sys-tem lands (all within the Los Padres NationalForest) include Little Sur River, Big Sur River,

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Chapter 4

Habitat: The following synopsis is fromMoyle et al. (1995). Major streams in south-ern California originate in the coastalmountains and many cross broad alluvial ar-eas before flowing into the sea. Theselow-elevation alluvial flats present inhospita-bly warm and fluctuating temperatures andstreamflows tend to be intermittent in thesesections. The higher elevation headwaters,therefore, are the primary spawning and rear-ing areas for steelhead. It is likely that thelargest steelhead populations historically oc-curred in major streams where the upstream

Big Creek, Alder Creek, San Carpoforo Creek,and Morro Creek.

Maps of the southern California ESU inthe west coast steelhead status review (NMFS1997a) show it extending from the SantaMaria River south to the Mexican border.However, the final rule on listing (NMFS1997b) defines the ESU as extending southto “the southern extent of the species’ range,”which is defined as Malibu Creek. This leavessome uncertainty as to whether a re-establishedpopulation south of Malibu Creek would beconsidered part of this ESU and recognizedas an endangered species. The primary streamssupporting steelhead runs in this ESU are theSanta Ynez River, Gaviota Creek, VenturaRiver, Santa Clara River (including SespeCreek) and Malibu Creek. Total run sizes inall of these streams were less than two hun-dred adults.

Historically, winter-run southern steelheador coastal rainbow trout moved up mostcoastal streams in central and southern Cali-fornia (Behnke 1992), although spawningsuccess south of the Los Angeles Basin mayhave been sporadic (Swift et al. 1993). NowMalibu Creek, Los Angeles County, is thesouthernmost stream recognized as support-ing a persistent spawning steelhead population(NMFS 1997b)(fig. 4.6). However, in April1999 trout believed to be southern steelheadwere found in a tributary of San Mateo Creekin San Diego County (A. Vejar, CDFG pers.comm). Tissue samples of these fish were col-lected for DNA analysis to determine if theyare indeed steelhead.

spawning and rearing habitats were closest tothe ocean, such as in the Ventura, Santa Clara,and Santa Ynez rivers. Streams still support-ing steelhead runs today are primarily in smalldrainages whose headwaters are in mountainsvery close to the coast (e.g., the Santa Lucia,Santa Ynez, and Santa Monica mountains).These streams tend to be the only ones thatdon’t have impassible barriers between spawn-ing habitats and the ocean.

Conservation Considerations: The exten-sive decline of steelhead in central andsouthern California is due mostly to in-streamwater developments that have resulted in in-adequate flows, flow fluctuations, blockages,and dewatering of portions of rivers (NMFS1997a). Suitable spawning and rearing habi-tats on national forest system lands arefrequently located in upper elevation areasabove currently impassable barriers. Efforts areongoing to develop a strategy for restoringsteelhead populations along the central coastand within the Los Padres National Forest.There has also been interest in trying to re-store habitat conditions for steelhead on SanMateo Creek in San Diego County (A. Vejar,CDFG, pers. comm.).

Mojave tui chub (Gila bicolor mohavensis)Status and Distribution: The Mojave tui

chub was federally listed as endangered in1970. The one remaining population withinthe assessment area is on lower Deep Creekon the San Bernardino National Forest. Un-fortunately, this population has hybridizedextensively with introduced arroyo chub (Swiftet al. 1993).

Habitat: The Mojave tui chub’s nativerange is restricted to the Mojave River and itstributaries (Swift et al. 1993).

Conservation Considerations: Moyle(1976) believed that the arroyo chubs hadeliminated the Mojave chubs in Deep Creek,but a hybrid collected in 1991 showed thatthe parental influence of both species still ex-ists (Swift et al. 1993). It is important to pre-vent further introductions of arroyo chubs intoDeep Creek.

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Figure 4.6. Current distribution of southern steelhead in the assessment area and the boundary between thesouth-central and southern California ESUs.

Arroyo chub (Gila orcutti)Status and Distribution: The arroyo chub

is a California Species of Special Concern. Itsstatus is interesting in that it is now most abun-dant in areas outside of its native range (Swiftet al. 1993). It was widely introduced in the1930s and 1940s, as bait with trout plants orwith mosquitofish, and now occurs in manyreservoirs and in central-coast and desert-sidestreams that are outside its native range (Swiftet al. 1993). Arroyo chubs are native to theLos Angeles, San Gabriel, Santa Ana, SantaMargarita, and San Luis Rey rivers and toMalibu and San Juan creeks (Moyle et al.1995). They have been successfully introduced

into the Santa Clara, Santa Ynez, Santa Maria,Cuyama, and Mojave river systems and othersmaller coastal streams (e.g., Arroyo GrandeCreek) (Swift et al. 1993; Moyle et al. 1995).

A number of native arroyo chub popula-tions occur in the assessment area. On theAngeles National Forest, it is in PacoimaCreek, Big Tujunga Creek, the west, east, andnorth forks of the San Gabriel River, CattleCanyon and Bear Creek. On the ClevelandNational Forest, it is in San Juan Creek,Trabuco Creek, the West Fork of the San LuisRey River and Agua Caliente Creek (aboveLake Henshaw). The largest population is

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Chapter 4considered to be in the West Fork of the SanGabriel River (Wells et al. 1975).

Habitat: Arroyo chubs are found in slow-moving or backwater sections of low-elevationstreams (Moyle et al. 1995). Wells et al. (1975)describe physical characteristics of stream siteswhere arroyo chub were collected.

Conservation Considerations: It is impor-tant to identify and maintain arroyo chubpopulations within the species’ native range.This can be achieved by ensuring that thereare adequate stream flows to maintain areasof permanent, year-round water in each of theoccupied streams. Moyle et al. (1995) iden-tify the West Fork of the San Gabriel River asa particularly important refugia for this spe-cies. A potential problem in some areas isintroduced red shiners, which may competi-tively exclude chub in some areas (Moyle etal. 1989). Red shiners are known to occur inBig Tujunga Creek below Big Tujunga Reser-voir.

Santa Ana speckled dace(Rhinichthys osculus)

Status and Distribution: The Santa Anaspeckled dace is a Forest Service Region 5 Sen-sitive Species and a California Species ofSpecial Concern. Its historic range is low-elevation streams in the Los Angeles, SanGabriel and Santa Ana river systems (Swift etal. 1993). The largest remaining populationis within the Angeles National Forest on lowerreaches of the east, north, and west forks ofthe San Gabriel River including Cattle Can-yon, Bear Creek and Fish Canyon (Swift et al.1993). Other reported occurrences on theAngeles include Pacoima Creek, Little TujungaCreek and Big Tujunga Creek (Moyle et al.1989), but more recent information indicatesthese populations may now be extinct (Moyleet al. 1995).

On the San Bernardino National Forest,small speckled dace populations are reportedfrom the North Fork of Lytle Creek, CajonWash, Lone Pine Canyon, Strawberry Creek,Plunge Creek, City Creek, Mill Creek (thispopulation is actually just downstream of theSan Bernardino National Forest boundary),

and the South Fork of the San Jacinto River(Moyle et al. 1995; S. Loe, SBNF, pers.comm.). On the Cleveland National Forest,there is a small population on Santiago Creek(R. Fisher, USGS Biological Resource Divi-sion, pers. comm.) and potentially in SilveradoCanyon (a historic population that may havebeen extirpated) (Moyle et al. 1995).

A genetically different form of speckleddace occurs in San Luis Obispo and northernSanta Barbara counties. The “San Luis Obispospeckled dace” occurs within the Los PadresNational Forest on the Cuyama and Sisquocrivers, and Manzana and San Luis Obispocreeks (Swift et al. 1993).

Habitat: The Santa Ana speckled dace re-quires permanent flowing streams with sum-mer water temperatures of 17 to 20 degreesCentigrade. The dace inhabit shallow cobbleand gravel riffles (Wells et al. 1975). Deinstadtet al. (1990) provide a detailed description ofspeckled dace habitat in the West Fork of theSan Gabriel River.

Conservation Considerations: Surveys areneeded to better determine the current distri-bution and abundance of speckled dace. Theprimary threat to most of the small popula-tions is maintaining areas of permanent,year-round surface water. Some populations(e.g., Silverado Canyon) suffered severe lossesor extirpation during the drought in the late1980s because streams dried up. Habitat deg-radation and the establishment of red shinersin Big Tujunga Canyon are cited as a cause ofspeckled dace decline (Moyle et al. 1989). Thewest, north, and east forks of the San GabrielRiver are identified as the best remaining habi-tat for Santa Ana speckled dace (Moyle et al.1995).

Santa Ana sucker(Catostomus santaanae)

Status and Distribution: The U.S. Fishand Wildlife Service has made a determina-tion that listing of the Santa Ana sucker asthreatened or endangered is warranted butprecluded at this time due to other pressingconcerns (P. Barrett, USFWS, pers. comm.).

130

Figure 4.7. Current distribution of the Santa Ana sucker.

The historic range of this species islow-elevation streams in the Los Angeles, SanGabriel and Santa Ana river systems (Swift etal. 1993). Remaining native populations areconcentrated within the Angeles NationalForest in the east, north, and west forks of theSan Gabriel River (including Cattle Canyonand Bear Creek), and Big Tujunga Creek (fig4.7). The only other native population is inthe lower Santa Ana River, outside the assess-ment area. Santa Ana suckers historicallyoccurred in the upper Santa Ana River, onCajon and City creeks in the foothills of theSan Bernardino Mountains, and in SantiagoCreek in the foothills of the Santa Ana Moun-tains (Moyle et al. 1995).

Introduced populations of the Santa Anasucker are present in the Santa Clara River,Sespe Creek, Piru Creek and San FrancisquitoCreek. Some of these introduced populationsare within the Los Padres and Angeles nationalforests. Hybridization with the non-nativedusky sucker (Catostomus fumeiventris) is ap-parently a problem in the Sespe Creek andlower Santa Clara River populations, but theupper Santa Clara River (Soledad Canyon)population has not been affected (Greenfieldet al. 1970, Swift et al. 1993).

Habitat: Santa Ana suckers are native tomany of the same streams as the speckled daceand have similar habitat requirements. Pre-ferred substrates are generally coarse gravel and

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Chapter 4

Habitat: Sticklebacks prefer quiet-waterhabitat like pools with abundant aquatic veg-etation, backwater areas, and stream marginswhere water velocity is low (Moyle et al. 1995).

Conservation Considerations: Currently,arundo is being removed along SanFrancisquito Creek and Soledad Canyon toincrease available surface water and improvehabitat for the stickleback. These localizedpopulations are vulnerable to a wide varietyof threats and require site-specific attention.

The Shay Creek stickleback is highly vul-nerable to extinction because of the tenuousnature of the water supply in Shay Creek. Ef-forts are ongoing to secure a dependable supplyof water and to establish additional popula-tions.

Partially armored threespine stickleback(Gasterosteus aculeatus microcephalus)

Status and Distribution: The partially ar-mored threespine stickleback is a Forest ServiceRegion 5 Sensitive Species. Swift et al. (1993)report that native populations of this subspe-cies are widespread north of Point Conceptionbut declining rapidly to the south. Recentrecords (1991 onward) south of the Los

boulders, and suckers are often associated withalgae, but not macrophytes (Moyle et al.1995). Additional habitat and life history in-formation for this species can be found inGreenfield et. al. (1970) and Moyle et al.(1995).

Conservation Considerations: The Ange-les National Forest is the primary refugia forthe Santa Ana sucker, and its few remainingpopulations require site-specific managementattention. The primary threats to these popu-lations are habitat degradation, streamflowalterations, and introduced species. Mining ac-tivities such as suction dredging are occurringin the upper San Gabriel River and have beenimplicated in the decline of suckers in CattleCanyon (Moyle et al. 1995).

Variable and sometimes extreme releasesof water from Big Tujunga and Cogswell res-ervoirs are constant threats to suckerpopulations on Big Tujunga Creek and theWest Fork of the San Gabriel River (Moyle etal. 1995). Red shiners, which have been in-troduced into Big Tujunga Creek, are apotential egg predator, and green sunfish arelikely to prey on juveniles. The elimination ofSanta Ana suckers from the upper Santa AnaRiver in the San Bernardino Mountains islargely attributed to predation by introducedbrown trout (Moyle et al. 1995). The west,north, and east forks of the San Gabriel Riverare identified as the best remaining habitat forSanta Ana suckers (Moyle et al. 1995).

Unarmored threespine stickleback(Gasterosteus aculeatus williamsoni)

Status and Distribution: The unarmoredthreespine stickleback was federally listed asendangered in 1970. Historically widespreadand abundant in the Los Angeles Basin, it isnow restricted to three areas in the upper SantaClara River watershed: an 8-mile stretch ofSoledad Canyon, a portion of upper SanFrancisquito Canyon and in Escondido Can-yon (a tributary of Agua Dulce Canyon) (Swiftet al. 1989). All of these populations are withinor near the Angeles National Forest (fig. 4.8).A recovery plan exists for this species (USFWS

1985) and a recovery team is in place that co-ordinates conservation activities.

The Shay Creek threespine stickleback isa morphologically similar, yet genetically dis-tinct population that occurs at elevations over6,000 feet in Baldwin Lake and its main tribu-tary, Shay Creek, in the eastern San BernardinoMountains (Haglund and Buth 1988). Thisstickleback is highly imperiled. Baldwin Lakeis ephemeral; thus, Shay Creek is the primaryrefugia for the fish. However, Shay Creek ispredominantly on private land and extractionof surface and groundwater in this basin hasreduced the availability of water in the creek.The one remaining population within ShayCreek exists in a small pool that must havewater artificially pumped in to sustain it. Atransplant population from Shay Creek hasbecome established on the San BernardinoNational Forest in an artificial pond inSugarloaf Meadows (Malcolm 1992).

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Angeles Basin are from the Santa Ana Moun-tains (Trabuco Creek in and below O’NeilPark, upper San Juan Creek near the mouthsof Hot Spring and Cold Spring canyons, andupper reaches of Bell Canyon on Starr Ranch)and the South Fork of the San Jacinto Riverbelow Lake Hemet (Swift et al. 1993).

To the north, partially armored stickle-backs occur in the Santa Clara, Ventura, andSanta Ynez rivers as well as many coastalstreams in Santa Barbara and San Luis Obispocounties. Other southern streams where na-tive populations of partially armoredsticklebacks historically occurred (and may stilloccur) include San Mateo Creek, Santa

Figure 4.8. Current distribution of the unarmored threespine stickleback.

Margarita River, and the San Luis Rey River(Swift et al. 1993). They were apparently ab-sent from streams in the Los Angeles Basininhabited by the unarmored threespine stick-leback.

Partially armored sticklebacks have beenwidely introduced into streams in associationwith trout plants. Established populations thatare believed to be the result of such introduc-tions can be found in Big and Little Rockcreeks (Angeles National Forest), HolcombCreek, Lake Arrowhead, and Big Bear Lake(San Bernardino National Forest), and theSweetwater River and Pine Creek (ClevelandNational Forest) (Swift et al. 1993).

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Chapter 4Habitat: They inhabit low-gradient, low-

elevation streams with characteristics similarto those described for the unarmoredthreespine stickleback.

Conservation Considerations: Similar tothose described for other native fish. Stickle-backs are hardy fish; the primary threat tonative populations is maintaining areas of per-manent, year-round surface water.

Tidewater goby (Eucyclogobius newberryi)Status and Distribution: The tidewater

goby was federally listed as endangered in1994. The assessment area extends to the coastonly for a small stretch in the northern SantaLucia Range (Monterey District, Los PadresNational Forest). None of the coastal streamsin this area are known to support populationsof the tidewater goby. The coastline is steepin this area and suitable lagoon habitats areabsent (Swift et al. 1989).

Habitat: Tidewater gobies are restricted tocoastal, brackish-water habitats (Swift et al.1989).

Conservation Considerations: The tide-water goby is a species whose conservation canbe minimally influenced by management ofpublic lands within the assessment area.

Aquatic/Upland Amphibians and Reptiles

Six amphibian and three reptile species(table 4.5) are dependent, to varying degrees,on aquatic habitats for some part of their lifecycle. These are collectively referred to asaquatic/upland species, because upland habi-tats in the vicinity of stream courses or waterbodies are also very important to their sur-vival.

Coast Range newt (Taricha torosa torosa)Status and Distribution: The Coast Range

newt is a California Species of Special Con-cern. It occurs along low-elevation streamsmostly near the coast. Newts occupy a num-ber of drainages along the southern Montereycoast, many within the Los Padres NationalForest. These include the upper Carmel River,Big Sur River, Big Creek, Devil’s Canyon,

Willow Creek, and San Carpoforo Creek.Many of the occupied streams in San LuisObispo and Santa Barbara counties are alongthe immediate coast and off of National For-est System land. However, newts do occur onnational forest system land in Lopez Canyon,East Fork of Morro Creek, Rincon Creek, andprobably the upper end of several other streamsdropping out of the Santa Ynez Mountains(Jennings and Hayes 1994).

South of the Santa Clara River, CoastRange newt populations are scarcer (Jenningsand Hayes 1994). Outside the assessment area,they occur in at least eight small, coastalstreams coming out of the Santa MonicaMountains (Gamradt and Kats 1996). In theSan Gabriel Mountains, they are known to bepresent in the east and west forks of the SanGabriel River, Bear Creek, San Dimas Creek,Big Dalton and Little Dalton canyons. Thereare historic records from other streams on thecoastal side of the San Gabriels, so they maystill be present in additional drainages.Jennings and Hayes (1994) show one mappednewt location in the San Bernardino Moun-tains, but they do not describe it and we arenot aware of any recent sightings in this range.

On the Cleveland National Forest, newtsoccur in a series of parallel drainages on thecoastal side of the Santa Ana Mountains, in-cluding Black Star Canyon, Silverado Canyon,Trabuco Creek, San Juan Creek, San MateoCreek, Devil’s Canyon, and Tenaja Creek. Justoff the forest in Camp Pendleton they alsooccur on San Onofre Creek, Santa MargaritaRiver, and DeLuz Creek. In the San Diegoranges, there is a disjunct population of CoastRange newts in three adjacent streams com-ing out of the Cuyamaca Mountains—CedarCreek, Boulder Creek, and Conejos Creek.

Habitat: Coast Range newts breed instreams and ponds but spend much of the yearaway from water. They generally prefer rockycanyons that contain streams with well-developed pools (Fisher and Case 1997).

Conservation Considerations: Betterdocumentation on the full extent of CoastRange newts in the southern California

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Aquatic/UplandAnimals of Concern

federal status

(1)Knowledgeof SoCalLocations

(% on NFs)

(5)Conser-vation

Category

(4) Pop.Trend

(3)Vulner-ability

on NFs

(2) areas occupied or estimated # of occurrences if spp. localized

San Bern. NFCleveland NF Angeles NF Los Padres NFSan

DiegoRngs

SanJacMts

SntaAnaMts

SanBernMts

No.SL

Rng

So.SL

Rng

SanGabMts

Cas-taic

Rngs

So.LP

Rngs

national forests is needed. They may be morewidespread than is documented here, particu-larly on the Los Padres National Forest. Recentgenetic studies by Dave Wake and others haveshown that newt populations in Orange andSan Diego counties (Cleveland National For-est) may represent a distinct species from thosenorth of the Los Angeles Basin (Fisher and Case1997).

Predatory non-native species, mainte-nance of adequate stream flows, water quality,and collecting appear to be the biggest factorsaffecting newt viability on public lands. Adultnewts are known to be highly toxic to preda-

tors and thus not at risk to introduced preda-tory animals. However, a recent study foundthat newt egg masses and larvae in the SantaMonica Mountains were readily consumed bycrayfish and mosquitofish (Gamradt and Kats1996). They documented the disappearanceof breeding newts in three drainages after cray-fish, mosquitofish, or both were introduced.On one of these drainages, they even observedrecovery of successful newt reproduction af-ter crayfish had been washed out of the streamduring heavy winter rains (Gamradt and Kats1996).

Table 4.5. Amphibians and reptiles associated with aquatic and upland habitats that receivedindividual consideration.Displayed for each species: (1) the level of knowledge about where it occurs in southern California and, inparentheses, the estimated percentage of locations that are on national forest system lands; (2) the mountainsubareas occupied (y = occurs in breeding season, h = historically occurred, p = potentially occurs, t = transient,w = winter visitor)—if the species is localized and data are available, the approximate number of occurrences may bedisplayed; (3) the vulnerability of populations on national forest system lands to existing threat factors; (4)population trends; and (5) the assigned conservation category.

1Jennings and Hayes (1994)2USFWS determination as described in listing decisions.

AmphibiansCoast Range newt High 3 6-8 p p 5-10 p 4-8 2-5 5-10 Mod Decl1 Site

(20-50%) specific

Western spadefoot toad Mod y y p p p y Mod Unkn Landscape(< 5%) level

Arroyo SW toad High ~19 ~8 1 3-5 3-6 3 ~10 0 1-2 High Decl2 Site endangered (30-50%) specific

CA red-legged frog Mod-High h/p 1 h h h 1-2 ~20 ~12 ~15 Mod Decl2 Site threatened (20-40%) specific

Foothill yellow- High h h h h/p 2-5 High Decl1 Site legged frog (10-30%) specific

Mountain yellow- Mod h/p 4-5 1-3 4-5 High Decl1 Site legged frog (> 80%) specific

ReptilesSW pond turtle High ~8 ~5 h/p 2 ~5 h/p ~25 ~15 ~15 Mod Decl1 Site

(30-60%) specific

South coast red-sided Low 1 1 0 0 0 0 1-2 Mod Decl1 Site garter snake (< 10%) specific

Two-striped garter snake Mod >25 >10 5-10 5-10 >10 5-10 >25 >10 5-10 Mod Decl1 Landscape

(40-70%) level

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Chapter 4On Boulder Creek on the Cleveland Na-

tional Forest, sudden large releases of water inmid-summer from an upstream reservoir oc-cur occasionally and appear to be negativelyaffecting newt reproductive success by flush-ing eggs and larvae downstream. Collectingof newts for the pet trade has historically beena major problem and may continue to be insome areas. Boulder Creek Road has histori-cally been a collecting spot (J. Copp, CA Acad-emy of Sciences, pers. comm.), and todaynewts can be readily found a half-mile or moreabove and below the road crossing but are in-creasingly rare as you approach the road.

Western spadefoot toad(Spea [Scaphiopus] hammondii)

Status and Distribution: The westernspadefoot is a California Species of SpecialConcern. Known localities for this species arepredominantly outside the assessment area, inlow-elevation coastal and inland valleys. It isreportedly abundant on the Camp PendletonMarine Corps Base along the northern SanDiego County coast (Holland and Goodman1998). Most known locations within or nearthe assessment area are in the coastal foothillsof San Diego County (e.g., Japatul Valley, OtayLakes, Santa Maria Valley, and WarnerSprings) (Ed Ervin and Joe Copp, pers.comm.) and Santa Barbara and San LuisObispo counties (e.g., Santa Maria Valley, andCuyama Valley) (Jennings and Hayes 1994).The toads also have been observed in the foot-hills of the Santa Ana Mountains at StarrRanch (Fisher and Case 1997) and the SantaRosa Plateau (Jennings and Hayes 1994).

Habitat: Western spadefoots occur incoastal valley habitats, valley-foothill grass-lands, coastal scrub, and chaparralcommunities up to approximately 3,000 feetin elevation (Ed Ervin, in litt.). Within thisrange, spadefoots are confined to areas withrelatively flat or low-gradient topography thatsupports the shallow ephemeral-pool habitatthey require for breeding. They are adaptedfor survival in dry, upland habitats. To avoiddesiccation, spadefoot toads spend the driermonths of the year inactive and hidden un-

derground. The toad uses its spadelike hindfoot to excavate its own retreats in loose orsandy soils. In areas where friable soils are notavailable, small mammal burrows are oftenused. Following spring rains, westernspadefoots congregate where there is pooledwater. Breeding takes place in shallow ephem-eral pools that form on valley floors, on ridgeand mesa tops, or in quiet drainages on low-gradient slopes above first-order streams.

Conservation Considerations: More com-plete information is needed on the distributionof western spadefoots on public lands in theassessment area. Threats to the spadefoot toadinclude destruction of breeding pool habitat,obstructions to migratory routes betweenbreeding sites and upland habitats, and highlevels of mortality along roads. Changes to thelength of time a breeding pool remains fullcan have significant negative effects on repro-ductive success. Pool “enhancements” thatmake them perennial water bodies create habi-tat for exotic species to invade and becomeestablished.

Arroyo southwestern toad(Bufo californicus)

Status and Distribution: The arroyosouthwestern toad was federally listed as en-dangered in 1994 (USFWS 1994). The entirerange of the arroyo toad in the United Statesis within or near the assessment area. The spe-cies also extends down into Baja California,Mexico. Based on our GIS database, approxi-mately 36 percent of occupied arroyo toadhabitat is on national forest system lands (fig4.9)—16 percent on the Los Padres NationalForest, 12 percent on the Cleveland NationalForest, 6 percent on the Angeles National For-est, and 2 percent on the San BernardinoNational Forest.

On the Los Padres National Forest, arroyotoads are concentrated in a small number oflocations. Substantial populations exist on PiruCreek including lower reaches of Agua BlancaCreek, Sespe Creek, and interconnected reachesof the upper Santa Ynez River, Mono Creek, andIndian Creek. A smaller population occurs along

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Figure 4.9. Current and historic locations of the arroyo toad within and adjacent to the assessment area.Approximately 36 percent of existing arroyo toad locations are on national forest system lands.

reaches of Kitchen and Morena creeks, PotreroCreek, the Sweetwater River, the upper SanDiego River, Santa Ysabel Creek and associ-ated lower reaches of Temescal Creek (PamoValley), the upper forks of the San Luis ReyRiver (above Lake Henshaw) including AguaCaliente Creek, Temecula Creek includinglower reaches of Arroyo Seco Creek, San MateoCreek, San Juan Creek, and Trabuco Creek.One population that is predominantly on na-tional forest system land occurs along Pine Val-ley Creek and several of its tributaries.

On the Angeles National Forest, arroyotoad populations exist along Castaic Creek,

the Sisquoc River. All of these Los Padrespopulations are predominantly on nationalforest system land. The northernmost popu-lation of arroyo toads, on the San Antonio Riverin Monterey County, lies just off the forest onthe Fort Hunter Liggett Military Reservation.

Arroyo toad populations on the ClevelandNational Forest and surrounding lands aremore numerous, but many appear to be smallin size. Most of the populations occur rightalong the forest boundary with the bulk ofprime breeding habitat often lying just offnational forest system land. This is the case atCottonwood Creek which includes lower

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Chapter 4Big Tujunga Creek including associated lowerreaches of Mill and Alder creeks, Arroyo SecoCreek, and on the desert side of the SanGabriel Mountains along Little Rock Creek.These populations lie near the forest bound-ary and, in some cases, extend beyond it.

On the San Bernardino National Forest,arroyo toad populations exist on tributaries ofthe Mojave River including lower Deep Creek,the West Fork of the Mojave River, the EastFork of the Mojave River (Miller Canyon),and Little Horsethief Creek. They also occuron lower portions of the Whitewater River andprobably still occur on lower reaches of theSan Jacinto River and adjacent Bautista Creek.

Habitat: Arroyo toads breed and depositegg masses in shallow, sandy pools along low-gradient sections of streams. These streams areusually bordered by sand-gravel flood terraces(USFWS 1999a). The flood terraces and otherupland streamside habitats are important forforaging and overwintering sites (fig 4.10). Ar-royo toads have been detected up to one kilo-meter from a water course (Holland andGoodman 1998). Many arroyo toad popula-tions occur along streams that do not normallyflow year-round. The largest populations tendto occur in broad floodplains along wide, shal-low streams. However, arroyo toads do existin some small ephemeral drainages (e.g., In-dian Flats area, Cleveland National Forest). Itis a low-elevation species, with known loca-tions extending from sea level to about 4,400feet.

Figure 4.10. An arroyo southwestern toad emergingfrom the sand on a streamside terrace. ROBERTGOODMAN, JR

Conservation Considerations: Arroyotoad populations are localized and face a vari-ety of threats. Many populations lieimmediately below major dams. The mannerin which water is released from upstream res-ervoirs can greatly influence arroyo toadreproductive success (Sweet 1992) (see “Ef-fect of Dams” section, chapter 3). Recentcoordination between various governmentagencies resulted in releases from PyramidDam that more closely mimic natural flowsin lower Piru Creek (Sweet 1992). The modi-fied releases have benefited arroyo toads in thatdrainage (USFWS 1999a).

Predatory, non-native species are a majorthreat to arroyo toads. Bullfrogs have beenobserved to eat juvenile and adult arroyo toads(Sweet 1993). A number of warm-water fishes(e.g., green sunfish, bluegill, largemouth bass,and black bullheads) and crayfish have beenshown to feed on arroyo toad larvae and cancause high larval mortality in breeding pools(Sweet 1992). These species occur in many ofthe streams occupied by arroyo toads (see “In-vasive, Non-Native Species” section, chapter3). In areas close to human development, Ar-gentine ants have spread into riparian areasand are reducing the native ant fauna (Ward1987, Holway 1995). Native ants are a majorfood source for arroyo toads; thus, they maybe negatively affected by the continued spreadof Argentine ants.

Introduced plants are also a problem insome areas. Tamarisk and arundo colonizenewly created flood terraces and can formdense masses of vegetation. These dense standshave higher rates of evapotranspiration thando native vegetation, thereby decreasing theamount of available surface water. They alsostabilize stream terraces, which helps to deepenflood channels, resulting in habitat unsuitablefor arroyo toads (USFWS 1999a).

Campgrounds and roads within or in closeproximity to arroyo toad breeding pools haveresulted in toads and their egg masses beinginadvertently crushed by vehicle and foottraffic and disturbed by waterplay. There are anumber of national forest campgrounds

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and banks, has occurred on Little HorsethiefCreek on the San Bernardino National Forest(USFWS 1999a). Drawdown of surface wa-ter from wells is also a concern.

California red-legged frog(Rana aurora draytonii)

Status and Distribution: The Californiared-legged frog (fig. 4.11) has declined pre-cipitously over the last thirty to forty years andbecame federally listed as threatened in 1996.Once widespread in low-elevation streams insouthern California, the Central Valley, andthe Sierra Nevada foothills, it has been extir-pated from 70 percent of its former range(USFWS 1996a). Red-legged frogs historicallyoccurred on all four national forests (fig. 4.12)but now appear to be extirpated from theCleveland and San Bernardino. They also werethought to be extirpated from the Angeles,until a small population was discovered on SanFrancisquito Creek in 1999.

Red-legged frogs extend down into BajaCalifornia and there reportedly are still a num-ber of populations in Mexico (Welsh 1988).However, within the United States, there areonly three known populations remainingsouth and east of Ventura County. The south-ernmost locality is on the Santa Rosa Plateauon the southeastern flank of the Santa AnaMountains in Riverside County. It is near theCleveland National Forest but does notextend onto it. This population has been

located near arroyo toad breeding habitat—seven on the Los Padres National Forest, fouron the Angeles National Forest, and four onthe Cleveland National Forest (USFWS1999a). Seasonal closures and/or restrictionson vehicle access have recently been institutedat some of these campgrounds to reduce im-pacts (e.g., Beaver, Lion, and Mono camp-grounds on the Los Padres and Joshua TreeCampground on the Angeles). Road crossingsin toad habitat are also being evaluated andseveral on the Los Padres and Cleveland havebeen relocated or rebuilt to reduce impacts tobreeding pools.

Off-highway vehicle (OHV) activity inarroyo toad habitat is a problem in some ar-eas, particularly on desert-side streams (e.g.,Little Rock Creek, Mojave River, upper PiruCreek). Most of the OHV-related habitatdamage, at least on national forest systemlands, is the result of unauthorized travel offof designated routes into areas legally closedto such use; it is the actions of a few irrespon-sible individuals and represents a challenginglaw enforcement problem.

Livestock grazing in arroyo toad habitatcan cause trampling of toads and their eggmasses. It also can result in degradation to sandbars and terrace habitats that are importantto arroyo toads (USFWS 1999a). Over the lastten years, most riparian habitat on the south-ern California national forests has been for-mally excluded from grazing. However, manyareas are intermingled with private lands whereriparian grazing still exists. Maintenance offence lines to prevent cattle movement ontopublic portions of the riparian corridor is amanagement problem in some areas occupiedby arroyo toads.

Suction dredge mining and streamsideprospecting (see descriptions of these activi-ties in “Mining” section, chapter 4) have thepotential to cause impacts in several areas.Suction dredging has occurred on Piru Creekon the Los Padres National Forest and PineValley Creek on the Cleveland National For-est (USFWS 1999a). Prospecting activities,including the digging of pits in the stream bed

Figure 4.11. An adult red-legged frog at Cole Creekon the Santa Rosa Plateau. ROBERT GOODMAN, JR.

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Chapter 4

The greatest number of remaining red-legged frog populations are within Monterey(thirty-two occurrences), San Luis Obispo(thirty-six), and Santa Barbara (thirty-six)counties (USFWS 1996a). Approximately 20to 30 percent of these populations occur onstreams within the Los Padres National For-

Figure 4.12. Current and historic locations of the California red-legged frog along California’s southerncoast. Approximately 30 to 40 percent of red-legged frog populations are on national forest lands, all on theLos Padres National forest.

est (fig. 4.12). The remaining are concentratedin small streams along the immediate coast-line. Populations occurring within the LosPadres National Forest include Piru Creek,Sespe Creek, Ventura River, Matilija Creek,upper Santa Ynez River, Mono Creek, IndianCreek, Sisquoc River, Manzana Creek, La BreaCreek, Cuyama River, Alamo Creek, BranchCreek, Stone Creek, Trout Creek, Lopez Can-yon, San Carpoforo Creek, and the Little Surand Big Sur rivers. A number of the streams alongthe Santa Barbara and San Luis Obispo coastcontain red-legged frogs and the upper reaches

declining; recent surveys found fewer than fourmales and no females (D. Holland, pers.comm. 1998; R. Goodman, in litt. 1998).The other populations are both in western LosAngeles County in the Castaic Ranges region,on Amargosa and San Francisquito creeks. TheAmargosa Creek population is on private land.

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Habitat: Habitat of California red-leggedfrogs is characterized by dense, shrubby ripar-ian vegetation (e.g., arroyo willow, cattails, andbulrushes) associated with deep (greater than3 feet), still or slow-moving water (Hayes andJennings 1988). Red-legged frogs are highlyaquatic and need surface water for most, if notall, of the year. They can occur in ephemeralstreams, but probably only ones that containsome year-round surface water (Jennings andHayes 1994). They have been found at eleva-tions up to 5,000 feet (e.g., Doane Pond onPalomar Mountain) but historically were mostabundant in low-elevation streams.

Conservation Considerations: The disap-pearance of red-legged frogs from so much oftheir former range heightens the importanceof remaining populations on the Los Padresand Angeles national forests. Further surveysare needed to determine conclusively if thereare any remaining populations on the othertwo national forests. Historically occupiedhabitat still exists on those forests and mayprovide suitable sites for reintroduction intothe southern half of the assessment area.

Predatory, non-native fish and amphibiansare particularly significant threats to red-leggedfrogs. With few exceptions, red-legged frogshave disappeared from virtually all sites wherebullfrogs have become established (Hayes andJennings 1988; Fisher and Shaffer 1996;Moyle 1973). The only areas where the twospecies have managed to coexist for prolongedperiods is along the immediate coast, wherecool “fogbelt” temperatures appear to providered-legged frogs some competitive advantages(S. Sweet, UC Santa Barbara, pers. comm.).

Red-legged frogs appear more capable ofpersisting in the presence of non-native fish;however, there are still strong negative corre-lations between the abundance of such fishand these frogs (Hayes and Jennings 1988; Fisherand Shaffer 1996). Results of a recent study inartificial ponds showed that mosquitofish andbluegill were significant predators of red-leggedfrog larvae (Schmieder and Nauman 1994).

Impacts from campgrounds and roads aresimilar to those described for the arroyo toad,except that the more highly aquatic frogs areless likely to be affected by activities away fromthe streambed. Livestock grazing that resultsin a loss of riparian vegetation can be highlydetrimental to red-legged frogs. However, suchgrazing in riparian habitats is not authorizedat any of the occupied red-legged frog sites onnational forest system lands.

Maintenance of adequate stream flows andhigh water quality is a key issue for red-leggedfrogs. Water diversions, groundwater extrac-tion, and stock pond or small reservoirdevelopments can cause degradation or elimi-nation of habitat (USFWS 1996a).

Foothill yellow-legged frog (Rana boylii)Status and Distribution: The foothill yel-

low-legged frog is a Forest Service Region 5Sensitive Species and a California Species ofSpecial Concern. While still present on manystreams along the northern California coast,it has become extremely rare in the south(Jennings and Hayes 1994). Its range histori-cally extended to the San Gabriel River (Northand East forks), and included a number oflocations in the Castaic and southern Los Pa-dres ranges, including Elizabeth Lake Canyon,Piru Creek, Sespe Creek, Hopper Creek, SantaPaula Canyon, upper Santa Ynez River (atJuncal Campground), upper Indian Creek,and Santa Cruz Creek (near the Guard Sta-tion) (Zweifel 1955; J. Copp, CA Academyof Sciences, in litt.). However, foothill yellow-legged frogs have not been observed in or southof the southern Los Padres ranges since 1978.The last sighting was near Frenchman’s Flat alongPiru Creek in 1977 (Jennings and Hayes 1994).

Foothill yellow-legged frogs do still occur inseveral coastal drainages in northern San LuisObispo and Monterey counties (fig. 4.13). Theonly occupied drainages on national forest sys-tem lands are along the southern Monterey coast;they include the Big Sur River and Willow Creek.Further surveys are needed to determine the fullextent of foothill yellow-legged populations inthe northern Los Padres. They historically oc-curred in Lopez Canyon (Zweifel 1955).

of some these are within the Los Padres NationalForest (e.g., Tajiguas Creek, Toro Creek).

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Chapter 4

Mountain yellow-legged frog(Rana muscosa)

Status and Distribution: The mountainyellow-legged frog is a Forest Service Region5 Sensitive Species and a California Species ofSpecial Concern. Southern California popu-lations are also under consideration for federallisting as endangered. In southern California,these frogs are found in the San Gabriel, SanBernardino and San Jacinto mountains and

Habitat: Foothill yellow-legged frogs typi-cally inhabit small- to moderate-sized,perennial streams with at least some cobble-sized substrate (Hayes and Jennings 1988).Most current and historic localities in the as-sessment area are at elevations below 4,000feet. It is a highly aquatic frog and seldomfound more than one or two leaps from astream (Zweifel 1955).

Conservation Considerations: The foot-hill yellow-legged frog is extremely rare in theassessment area and should be given site-specific management attention. Threats to thisspecies are similar to those described for thered-legged frog. Predatory non-native fish andbullfrogs are apparently not present in the

Figure 4.13. Current and historic locations of mountain and foothill yellow-legged frogs.

southern Monterey and northern San LuisObispo coast streams still occupied by foot-hill yellow-legged frogs (D. Holland, pers.comm.). This may explain why the yellow-legged frogs are still there.

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at least historically on Palomar Mountain (fig.4.13) (Jennings and Hayes 1994). Small popu-lations of mountain yellow-legged frogs stillexist in the San Gabriel Mountains on upperLittle Rock Creek and along the upper SanGabriel River and several of its forks (Jennings1995a, 1998). They also may still be presentin Day Canyon (R. McKernan, San Bernar-dino Nat. History Museum, pers. comm.). Inthe San Jacinto Mountains, populations arestill present in Hall Canyon, Dark Canyon,Fuller Mill Creek, and the North Fork of theSan Jacinto River (Jennings 1998). They werehistorically collected on Snow Creek and re-portedly were observed in Andreas Canyon (R.McKernan, pers. comm.), but 1997 surveysat both those locations failed to detect them(D. Holland, pers. comm.).

In the San Bernardino Mountains, moun-tain yellow-legged frogs were recentlyrediscovered in City Creek (B. Matibag, pers.comm. 1998). They were reportedly sightedin Barton Creek in the late 1980s (R.McKernan, pers. comm.), but 1997 surveysin this area failed to detected them (D. Hol-land, pers. comm.). Other historic locationsin the San Bernardino Mountains include Si-beria Creek, Mill Creek, Plunge Creek, andWaterman Canyon. Focused surveys in 1997failed to detect mountain yellow-legged frogson any of these drainages (D. Holland, pers.comm.), although there was an independentreport of one such frog on Mill Creek (G.Cardiff, pers. comm.). At the one historic lo-cation on Palomar Mountain, a pond onDoane Creek, this species has not been seensince the 1970s and the pond is now overrunwith bullfrogs and exotic fishes (Jennings andHayes 1994).

Mountain yellow-legged frogs have de-clined precipitously in the southern Califor-nia mountains; Jennings and Hayes (1994)suggest that they have been extirpated from99 percent of their historic range in this re-gion. All of the remaining populations appearto be very small, most with less than fifteenadults observed.

Habitat: Mountain yellow-legged frogsinhabit high-elevation streams usually above4,000 feet. However, in the San GabrielMountains and perhaps other areas where thecharacteristics of mountain streams (i.e., steep,rocky canyons) extend to lower elevations,these frogs historically occurred at elevationsdown to 2,000 feet (e.g., Bear Creek and EveyCanyon) (G. Stewart, Cal. Poly Pomona, in litt.).

Conservation Considerations: Mountainyellow-legged frog populations within the as-sessment area are small, localized, andvulnerable to existing threats. They thereforewarrant site-specific management attention.

The primary threats to this species are (1)the increasing spread of non-native predatoryfish and amphibians (i.e., bullfrogs), (2) lossof breeding pools from siltation or decliningsurface water, and (3) disturbance of individu-als and egg masses from recreation and landuse activities. Jennings (1995a, 1998) foundpotentially impactive recreation activities (e.g.,people walking in the creek, swimming, leftbehind trash, trail crossings) occurring at themountain yellow-legged frog locations inDark Canyon, Fuller Mill Creek, Little RockCreek, and Vincent Gulch. He recommendsrerouting trails and campsites to steerrecreationists away from these key breedingareas. Jennings (1995) also observed placermining activity on the upper San GabrielRiver (East Fork) within the Sheep Moun-tain Wilderness Area. Associated with this un-authorized activity were trash and toxic ma-terials such as mercury being dumped intothe stream bed.

More survey work is needed to determineif additional populations exist and to betterdetermine the size of known populations. Re-introductions of mountain yellow-leggedfrogs to historically occupied sites may be anoption, particularly in the San Gabriel andSan Bernardino mountains where suitablehabitat is most widespread. However, the spe-cific habitat conditions necessary forreintroductions first need to be defined. Re-search done in high mountain lakes in theSierra Nevada has found mountain yellow-legged frogs to be largely intolerant of

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Chapter 4introduced predatory fish (i.e. trout), sincethey rarely persist in lakes where such fisheshave been introduced (Bradford 1989;Bradford et al., 1993). The fish apparentlyconsume frog egg masses and larvae. There isuncertainty about whether the effect of intro-duced trout is as strong in southern California,since the frogs occupy stream habitats ratherthan lakes. In August 1997 surveys of knownmountain yellow-legged frog locations,Jennings (1998) observed rainbow trout andno frogs in pools at two locations—VincentGulch (a fork of the upper San Gabriel River),and Fuller Mill Creek. The relationship be-tween introduced trout and yellow-leggedfrogs in southern California streams needs tobe better understood.

Southwestern pond turtle(Clemmys marmorata pallida)

Status and Distribution: The southwest-ern pond turtle is a Forest Service Region 5Sensitive Species and a California Species ofSpecial Concern. Pond turtles are consider-ably more abundant in the northern half ofthe assessment area (i.e., northwest of the SantaClara River). In the Los Padres National For-est there are forty to fifty streams that containpond turtle populations (USFWS 1993a),with the largest occurring on Piru Creek, SespeCreek, the Indian Creek/Mono Creek area, theSisquoc River/Manzana Creek area, AlamoCreek, Nacimiento River and Arroyo SecoCreek (D. Holland pers. comm.; Brattstromand Messer 1988). Populations also occuralong most of the drainages along the imme-diate coast in Santa Barbara and San LuisObispo counties.

South of the Santa Clara River, pond turtlepopulations have declined substantially bothin size and number (Holland 1991; Brattstromand Messer 1988). They still occur at over fiftysites, but most of these contain few turtles.Only six to eight sites contain populations ofthirty or more individuals (Holland 1991).There is one large pond turtle population onthe Angeles National Forest on the West Forkof the San Gabriel River below Cogswell Res-

ervoir. Small populations on the Angeles alsooccur on upper Castaic Creek, Aliso Canyon,Pacoima Creek, Little Tujunga Creek, BigTujunga Creek, the East Fork of the SanGabriel River, and possibly Big Dalton Creek.

On the San Bernardino National Forest,there may still be small pond turtle popula-tions in Cajon Wash, Deep Creek, and prob-ably the West Fork of the Mojave River belowSilverwood Lake. Pond turtles historically oc-curred in Andreas Canyon on the desert sideof the San Jacinto Mountains (Jennings andHayes 1994) and may still be present there.

Two large pond turtle populations occuron the Cleveland National Forest at San MateoCreek and Pine Valley Creek. Just outside theforest there are also sizable populations on theSanta Margarita River/Temecula Creek (con-nected drainages), on Aliso Creek in ChinoHills State Park (Goodman 1994), and onCole Creek within the Santa Rosa Plateau Pre-serve. Small populations also occur on TenajaCreek, the upper San Luis Rey River, SantaYsabel Creek, the upper San Diego River (in-cluding Cedar, Boulder and Conejos creeks),the upper Sweetwater River, and CottonwoodCreek above Barrett Lake.

Habitat: Pond turtles inhabit a wide vari-ety of low-elevation aquatic habitats generallybelow 4,000 feet elevation. In the assessmentarea, pond turtles are found primarily in riv-ers and streams that have persistent deep pools(Holland 1991). The pond turtle is a highlyaquatic turtle that moves onto land to repro-duce and overwinter (Jennings and Hayes1994). Along the central and southern coastof California, pond turtles may remain activeyear-round (Holland 1991).

Conservation Considerations: Pond turtlepopulations south of the Santa Clara River aresufficiently rare to warrant site-specific man-agement attention. The few remaining largepopulations deserve particular attention andadditional surveys are needed to determine thestatus of the others. Populations on the LosPadres are considerably more abundant andcan likely be conserved through general ripar-ian area management.

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The primary reason for pond turtle de-clines has been loss of suitable habitat. Thisloss has been greatest in the lower foothills andvalleys where pond turtles were historicallymost abundant (Holland 1991). Dams, diver-sions, and stream channelization have greatlyreduced the availability of persistent, pooledwater along low-elevation streams. Pondturtles do not do well in large reservoirs; theyfrequently inhabit stock ponds, but there areindications that reproductive success is poorin these habitats and they may constitute sinkhabitats (D. Holland, pers. comm.). The re-duced availability of water makes pond turtleseven more vulnerable to extended droughts.Monitored populations in San Mateo Creekand Pine Valley Creek declined dramaticallyin the early 1990s at the end of our last pro-longed drought (D. Holland, pers. comm.).Some small populations on highly intermit-tent streams probably disappeared completelyduring the drought.

Other threats include introduced preda-tory fish, bullfrogs, and collecting. Predatoryfish and bullfrogs impact reproductive successby consuming juvenile turtles. It can be diffi-cult to determine the severity of this impact;pond turtles are long-lived animals and canpersist in an area for many years even withoutsuccessful reproduction. However, a numberof pond turtle populations consist primarilyof older adults and are considered to be at risk(Holland 1991). Collecting of pond turtles isa significant problem in some easily accessibleareas.

South coast red-sided garter snake(Thamnophis sirtalis spp.)

Status and Distribution: The south coastred-sided garter snake is believed to be a dis-tinct taxon from red-sided garter snakes northof the Tehachapi Mountains and Carpinteria(Santa Barbara County) (Jennings and Hayes1994). It is known only from scattered locali-ties along the southern California coastal plain,from the Santa Clara River Valley south to thevicinity of San Pasqual Valley in San Diego

County. Historic localities on CampPendleton (San Diego County) are dominatedby tules, cattail, and willow (Holland andGoodman 1998).

The south coast garter snake has beensighted recently in only a few localities, someof which are near national forest system lands:the lower Santa Clara River, the lower SantaMargarita River, San Mateo Creek, the lowerSan Luis Rey River and above Lake Henshawalong the upper reaches of the same drainage(Jennings and Hayes 1994; Holland andGoodman 1998; R. Fisher pers. comm.). Thisspecies has not been extensively surveyed forand is regarded as difficult to detect. There ispotential for it to occur at low elevations (be-low 3,000 feet) on any or all of the fournational forests.

Habitat: The south coast garter snake oc-curs in marshy, permanent-water habitatsalong low-elevation streams (Jennings andHayes 1994).

Conservation Considerations: Surveysneed to be conducted for this species alongthe major low-elevation streams that extendonto national forest system lands. Given itsrarity, any occurrences of this species shouldbe give site-specific management attention.

Two-striped garter snake(Thamnophis hammondii)

Status and Distribution: The two-stripedgarter snake is a Forest Service Region 5 Sen-sitive Species and a California Species ofSpecial Concern. In a reversal of the patternexhibited by most aquatic species, the two-striped garter snake appears to have declinedmore in the northern portion of its range(Jennings and Hayes 1994). It is consideredto be most common in eastern San DiegoCounty, where it occurs in most foothill andmountain streams that have pools with per-sistent water (Jennings and Hayes 1994). Itstill occurs in all the mountain subareas withinthe assessment area but has disappeared frommany historic locations in the coastal basins.The assessment area and the coastal region tothe west make up almost the entire range ofthis species.

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Cooper’s hawk (Accipiter cooperi)Status and Distribution: The Cooper’s

hawk is a California Species of Special Con-cern. Cooper’s hawks are found in all themountain subareas, but they occur at low-densities and were not effectively monitoredin the riparian point-count surveys (i.e., onlyabout two per year were detected) (Stephensonet al. 1998). However, results from the BBSsuggest that Cooper’s hawks may be decliningstatewide (table 4.6) (Sauer et al. 1997).

Habitat: Cooper’s hawks typically nest inriparian forests, mountain canyons (Garrettand Dunn 1981), and oak woodlands (Unitt1984). They also utilize eucalyptus groves tosome degree and have been observed success-fully fledging young in residental areas.

Conservation Considerations: Cooper’shawk breeding habitat is declining on privatelands at the lower elevations; thus, publiclands in the assessment area are becomingincreasingly important to this species. How-ever, this hawk does not seem particularlyvulnerable to prevailing agents of change onpublic lands. Its broad distribution and lifehistory characteristics suggest it can be con-served through landscape-scale, habitat-based management.

Yellow-billed cuckoo(Coccyzus americanus occidentalis)

Status and Distribution: The yellow-billed cuckoo is state listed as endangered and

Habitat: Two-striped garter snakes inhabitperennial and intermittent streams from sealevel to over 7,000 feet (e.g., Tahquitz Valleyin the San Jacinto Mountains) (Jennings andHayes 1994). They also occupy stock pondsand other artificially created aquatic habitats.

Conservation Considerations: Althoughit is thought to be declining, the two-stripedgarter snake is considerably more commonthan the other aquatic amphibians and rep-tiles described above. For that reason webelieve it can be adequately conserved throughappropriate landscape-scale management ofriparian and aquatic habitats. However, giventhat national forest system lands are the pri-mary refugia for this species, there is a need tobetter determine the specific drainages whereit occurs. It is a relatively easy species to de-tect and, once inventoried, it would be easyto at least periodically monitor its presence orabsence in specific drainages over time.

Riparian Birds

The importance of riparian habitats tobirds has long been recognized and has led toan emphasis on research and monitoring ofthis group. In southern California, the endan-gered least Bell’s vireo has been the marqueeriparian bird over the last two decades. Morerecently the southwestern willow flycatcher hasalso become a focal species. To look morebroadly at the avian riparian community, in1988 the four southern California nationalforests initiated a broad-scale, coarse-filter ap-proach to annually monitor the abundance ofbirds in riparian habitats. A standardized ten-minute point count technique with threeindependent observers has been used to sampleabout two hundred permanent stations eachyear during the breeding season. These point-count stations are spread across more thantwenty drainages (fig 4.14).

Trends in the detection rates of specificbird species have recently been analyzed(Stephenson et al. 1998). Trends from thepoint-count data were compared with similartrend estimates from the North AmericanBreeding Bird Survey (BBS) (Sauer et al. 1997).

For our comparisons we used BBS trends from1980 to 1996 for all of California, the Cali-fornia foothills physiographic region, and theLos Angeles Ranges physiographic region. Sta-tistically significant trends in abundance wereobserved for a number of species; however, fewof our fine-filter species were detected oftenenough to reliably determine their trends(table 4.6).

Thirteen riparian bird species were iden-tified as being rare or potentially at risk andreceived individual consideration (table 4.7).Most of them are associated with low-eleva-tion riparian habitats.

146

Figure 4.14. Riparian bird point-count monitoring stations across the four southern California nationalforests. Birds were monitored annually at about two hundred stations from 1988 to 1997.

is a Forest Service Region 5 Sensitive Species.Yellow-billed cuckoos have been observed inthe breeding season at various locations alongthe central and southern California coast (e.g.,Prado Basin, lower San Luis Rey River, lowerSanta Ysabel Creek above Lake Hodges), butnot within the assessment area (Garrett andDunn 1981). There is very little potential habi-tat for this species on national forest systemlands in southern California.

Habitat: Yellow-billed cuckoos breed inbroad, well-developed, low-elevation riparianwoodlands.

Conservation Considerations: The yel-low-billed cuckoo is not known to occur

within the assessment area and the potentialto support a population is believed to be verylow. Therefore management activities on na-tional forest system lands in the assessmentarea are believed to have little influence onthe conservation of this species.

Black swift (Cypseloides niger)Status and Distribution: The black swift

is a local species of concern because (1) it hasspecialized nesting requirements that are foundin very few locations in southern Californiaand (2) most of its breeding localities arewithin the assessment area. Known nestinglocalities include Santa Anita Canyon and

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Wolfskill Canyon in the San Gabriel Moun-tains, Fallsvale in Mill Creek Canyon in theSan Bernardino Mountains, and TahquitzCreek in the San Jacinto Mountains (Garrettand Dunn 1981).

Habitat: Black swifts nest in rocky cliffsbehind waterfalls. They occur in mountainand foothill canyons that contain waterfalls.

Conservation Considerations: Since wa-terfalls are also popular recreation sites,management attention is needed to ensure thatblack swift nest sites are not disturbed.

Southwestern willow flycatcher(Empidonax traillii extimus)

Status and Distribution: A precipitous de-cline in the abundance of the southwesternwillow flycatcher led to its federal listing asendangered in 1995. Extensive loss of low-

Avg. # Point Counts BBS Routes — 1980 to 1996 observed 1988 to 1996 California CA Foothills LA Ranges

Species each year Trend P Trend P Trend P Trend P

Song sparrow 163 -3.6% 0.04 0.3% 0.76 1.6% 0.55 -6.1% 0.37

Yellow warbler 104 -0.1% 0.91 -3.0% 0.04 -5.0% 0.00 31.5% 0.00

Warbling vireo 43 7.6% 0.09 -2.0% 0.03 -2.9% 0.02

Lawrence’s goldfinch 21 -9.6% 0.04 0.7% 0.78 0.1% 0.97 -11.6% 0.12

Black-chinned hummingbird 19 -7.1% 0.04 -7.0% 0.03 -9.5% 0.01

Common yellowthroat 10 2.3% 0.66 5.1% 0.08

Swainson’s thrush 3 -6.0% 0.56

Red-shouldered hawk 3 -2.5% 0.75

Willow flycatcher** 2 Sample too small

Yellow-breasted chat 2 Sample too small 1.3% 0.25 0.9% 0.62

Cooper’s hawk 2 Sample too small -7.5% 0.02 -7.0% 0.03

American dipper 1 Sample too small

MacGillivray’s warbler** < 1 Sample too small

Tree swallow < 1 Sample too small

Least Bell’s vireo < 1 Sample too small

Black swift < 1 Sample too small

** Detections of these species were believed to be migrating birds based on time of year.

elevation riparian habitat across its range andbrood parasitism by the brown-headed cow-bird were identified as the primary causes ofits decline (USFWS 1995c). Its breeding rangeincludes southern California, Arizona, NewMexico, southern portions of Utah and Ne-vada, and western Texas (USFWS 1995c).

In southern California, the southwesternwillow flycatcher is considerably less abundantthan the least Bell’s vireo (fig. 4.15). It occursat fewer locations and in smaller numbers. Oneof the largest remaining populations is on theupper San Luis Rey River, partially within theCleveland National Forest (Unitt 1987).About eighteen to twenty-five pairs breed alonga 3-mile stretch of this river below Lake Henshaw(Griffith and Griffith 1995). A similar size popu-lation exists on the Santa Margarita River within

Table 4.6. Detection rates and, where possible, trends in abundance for sixteen riparian birds from thenational forest riparian point count study (1988 to 1996) and the Breeding Bird Survey (1980 to 1996). Thetrend value is the mean percent change per year in number of birds detected, based on the slope of aregression line. Statistically significant trend values (P < 0.10) are in bold. Detection rates were too low toproduce meaningful trends for many of our fine-filter species.

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Camp Pendleton. The only larger popula-tion in California occurs on the South Forkof the Kern River, where thirty-eight pairswere documented in 1997 (Whitfield et al.1997).

One to three breeding pairs have been ob-served annually between 1996 and 1998 onMill Creek near Mountain Home Village onthe San Bernardino National Forest. A size-able number of early-summer detections at

Riparian BirdsAnimals of Concern

federal status

(1)Knowledgeof SoCalLocations

(% on NFs)

(5)Conser-vation

Category

(4) Pop.Trend

(3)Vulner-ability

on NFs

(2) areas occupied or estimated # of occurrences if spp. localized

San Bern. NFCleveland NF Angeles NF Los Padres NFSan

DiegoRngs

SanJacMts

SntaAnaMts

SanBernMts

No.SL

Rng

So.SL

Rng

SanGabMts

Cas-taic

Rngs

So.LP

Rngs

Table 4.7. Riparian-associated birds that received individual consideration.Displayed for each species: (1) the level of knowledge about where it occurs in southern California and, inparentheses, the estimated percentage of locations that are on national forest system lands; (2) the mountainsubareas occupied (y = occurs in breeding season, h = historically occurred, p = potentially occurs, t = transient,w = winter visitor)—if the species is localized and data are available, the approximate number of occurrences may bedisplayed; (3) the vulnerability of populations on national forest system lands to existing threat factors; (4)population trends; and (5) the assigned conservation category.

BirdsCooper’s hawk Mod y y y y y y y y y Low Unkn Landscape

(30-60%) scale

Yellow-billed cuckoo Mod p Low Unkn Minimal (0%) influence

Black swift Mod p 2-3 3-5 3-5 p p p Mod Unkn Site(>75%) specific

SW willow flycatcher High 20+ 0 0 1 0 1-2 p 0 0 High Decl Site endangered (20-50%) specific

Tree swallow Low y t y y y p y y y High Unkn Landscape(< 5%) scale

Swainson’s thrush Low y y p/t p/t y y y y y Mod Unkn Landscape(10-30%) scale

American dipper Low 2-4 0-2 5-15 20-30 20-30 0-2 ~15 5-10 5-15 Low Unkn Landscape(> 75%) scale

Least Bell’s vireo High 15 1-2 0 0 0 1 25 0 0 High Incr/ Site endangered (< 3%) Decl2 specific

Warbling vireo Mod y y y y y y y y y Mod Unkn Landscape(30-60%) scale

Yellow warbler Mod y y y y y y y y y Mod Stab1 Landscape(30-60%) scale

Common High y y y y y y y y y Mod Unkn Landscape yellowthroat (< 30%) scale

Yellow-breasted Mod y y y y y y y y y Mod Unkn Landscape chat (< 20%) scale

Lawrence’s Mod-Low y y y y y y y y y Mod Decl1 Landscape goldfinch (30-60%) scale

1 based on USFS riparian point count results2 Bell’s vireo is increasing regionwide, but decreasing on national forest service lands

point-count stations on San FrancisquitoCreek in the Angeles National Forest suggestwillow flycatchers may breed along that drain-age. Also, a willow flycatcher was observedbuilding a nest along the Santa Clara River inSoledad Canyon just north of national forestsystem lands (D. Cooper, UC Riverside, inlitt.). There are currently no known breedinglocations on the Los Padres, although severalearly-summer detections have been made at

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Figure 4.15. Known locations of the southwestern willow flycatcher and least Bell’s vireo along the southernCalifornia coast.

are highly localized and variable in vegetationstructure, making it difficult to readily seewhat microhabitat features are being selected.One common denominator appears to be thepresence of perennial or near-perennial water.Whitfield and Enos (1996) measured thevegetative characteristics of willow flycatcherbreeding sites on the Kern River and foundthat all nesting territories had high vegetativevolume in the lower strata and high canopydensity.

point-count stations on several drainages. Itis unknown if they were residents or migrants.

Recent monitoring of the upper San LuisRey River population suggests that it is cur-rently stable (B. Haas, Varanus Consulting,pers. comm.). Populations on the SantaMargarita River and Prado Basin also appearstable, but willow flycatchers have not re-sponded to cowbird control with dramaticincreases as did the least Bell’s vireo at thosesame locations (L. Hays, USFWS, pers.comm.).

Habitat: The southwestern willow fly-catcher is a neotropical migrant that breeds inlow-elevation riparian habitats. Occupied sites

Conservation Considerations: Southwest-ern willow flycatcher populations within theassessment area are few and vulnerable to ex-isting threat factors. They therefore warrant

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vicinity of slow-moving or standing water(Garrett and Dunn 1981).

Conservation Considerations: More com-plete information is needed on the distributionof tree swallows on public lands in the assess-ment area. Ongoing surveys associated withthe development of breeding bird atlases inLos Angeles and San Diego counties shouldprovide much needed information. The de-cline of this species as a breeder in the regionis attributed to loss of low-elevation riparianhabitat and competition with starlings for nestcavities (Garrett and Dunn 1981).

Swainson’s thrush (Catharus ustulatus)Status and Distribution: There seems to

be broad consensus that Swainson’s thrushesare declining throughout California and havedisappeared from many areas (Garrett andDunn 1981; Unitt 1984; Stefani 1998). Re-sults from the BBS also show a downwardtrend, although it is not statistically signifi-cant. The status of Swainson’s thrushes withinthe assessment area is difficult to determinegiven the paucity of data on its distributionand abundance.

The Swainson’s thrush is a common springtransient and localized summer resident inlow-elevation riparian habitats in southernCalifornia. Breeding populations are report-edly more abundant from Santa BarbaraCounty north (Garrett and Dunn 1981).Knowledge of its distribution and abundancewithin the assessment area is poor. TheSwainson’s thrush’s apparent affinity for coastallowland habitats (Unitt 1984) reduces theamount of potential nesting habitat on na-tional forest system lands. Still, Swainson’sthrushes were detected repeatedly along sev-eral drainages during the annual riparian pointcounts conducted from 1988 to 1996 (table4.8). Some of these were probably transientbirds, but the locations provide a place to startwhen looking for nesting locations.

Habitat: The Swainson’s thrush occupieslow-elevation riparian habitats, typically indense thickets of willow and other hardwoodsalong the primary stream channel (R. Stefani,UC Davis, pers. comm.).

site-specific management attention. The up-per San Luis Rey River population is aparticularly significant resource and should bemanaged accordingly. Threats are similar tothose described for the least Bell’s vireo, al-though factors controlling willow flycatcherpopulation growth are not as well understood.

The South Fork, Kern River populationis the best studied. In the years prior to cow-bird control (1989 to 1992), nest parasitismrates averaged 62.5 percent. With cowbirdremoval (1994 to 1997), parasitism rates haveaveraged only 16.5 percent (Whitfield et al.1997). However, this improvement has not,as of yet, resulted in a significant increase inthe number of willow flycatchers (Whitfieldet al. 1997). The Cleveland National Foresthas trapped cowbirds annually along the up-per San Luis Rey River since 1992. Nestparasitism rates prior to cowbird trapping arenot known, but nest monitoring since the ini-tiation of trapping has detected very lowparasitism rates (less than 5 percent) (Griffithand Griffith 1995; B. Haas, pers. comm.).

More inventory work is needed to deter-mine the full extent of breeding willowflycatcher populations. Determining if breed-ing is occurring along San Francisquito Creekis a particular priority. In addition, a betterunderstanding is needed of the key factorlimiting the growth and expansion of south-western willow flycatcher populations.

Tree swallow (Tachycineta bicolor)Status and Distribution: The tree swal-

low is a rare summer resident in southernCalifornia. We found no confirmed breedinglocations on national forest system lands, al-though there likely are some. Most of thebreeding locations identified by Garrett andDunn (1981) are near the immediate coast(e.g. Morro Bay, Santa Maria River, and thelower San Luis Rey River). Two breeding lo-cations, Lake Henshaw and Wynola, arewithin the assessment area and close to theboundaries of the Cleveland National Forest.

Habitat: Tree swallows typically breed inlowland and foothill riparian habitats in the

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Chapter 4Conservation Considerations: Major

threats are loss of lowland riparian habitat andnest parasitism by brown-headed cowbirds(Garrett and Dunn 1981). Better informationon the distribution and abundance of theSwainson’s thrush within the assessment areais sorely needed. It is clearly not common andappears to be vulnerable to existing threat fac-tors.

American dipper (Cinclus mexicanus)

Status and Distribution: The Americandipper is a species of local concern because itis rare in southern California and most loca-tions are within the assessment area. Dippersare most common in the San Gabriel and SanBernardino mountains, with scattered occur-rences in some of the other mountain ranges.Known dipper nesting localities include Up-per Sisquoc Falls, Santa Paula Canyon, Agua

Cachuma Creek Santa Ynez River Los Padres 2 1

Santa Ynez River Santa Ynez River Los Padres 1 3

Elizabeth Lake Canyon Elizabeth Lake Canyon Angeles 2 3

San Francisquito Canyon San Francisquito Canyon Angeles 2 2

Little Tujunga Canyon Little Tujunga Canyon Angeles 2 2

Lower Big Tujunga Canyon Big Tujunga Canyon Angeles 3 4

Upper Big Tujunga Canyon Big Tujunga Canyon Angeles 1 3

Mill Creek (Big Tujunga) Big Tujunga Canyon Angeles 2 2

Arroyo Seco Creek Arroyo Seco Creek Angeles 2 2

Cajon Creek (Lost Lake) Cajon Creek San Bern. 2 1

Bautista Canyon San Jacinto River San Bern. 4 2

Silverado Canyon Silverado Canyon Cleveland 3 4

San Juan Creek San Juan Creek Cleveland 3 2

Long Canyon San Juan Creek Cleveland 2 1

Pine Valley Creek Pine Valley Creek Cleveland 1 2

Kitchen Creek Cottonwood Creek Cleveland 1 2

La Posta Creek Cottonwood Creek Cleveland 2 2

Morena Creek Cottonwood Creek Cleveland 2 1

Table 4.8. Locations where Swainson’s thrushes were detected multiple times in riparian pointcount surveys from 1988 to 1996. These surveys did not extend north of the Sisquoc River. Mostdetections were made during the month of May. Further survey work is needed to determine ifthese represent breeding locations or just birds migrating through the area.

Swainson Thrush Locations # of points

National # of Years where

Specific Drainage Primary Drainage Forest Detected detected

Blanca Creek and Sespe Creek (Los PadresNational Forest); Santa Anita Canyon and theupper forks of the San Gabriel River (AngelesNational Forest); Upper Santa Ana River, BearCreek and Mill Creek in the San BernardinoMountains and Tahquitz Creek and the NorthFork of the San Jacinto River in the San JacintoMountains (San Bernardino National Forest);and Pauma Creek on Palomar Mountain(Cleveland National Forest)(Garrett andDunn 1981; Unitt 1984; Lane 1985; Lentz1993).

Habitat: Dippers occupy fast-flowing,clear streams in mountain canyons (Garrettand Dunn 1981).

Conservation Considerations: Dipperhabitat is typically in remote canyons and vul-nerability to land use impacts is believed to below. The biggest threat is further impound-ment or diversion of streamflows.

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Least Bell’s vireo (Vireo bellii pusillus)

Status and Distribution: The least Bell’svireo was federally listed as endangered in1986. Its breeding range is restricted to south-ern California and northern Baja California,Mexico (USFWS 1998c). The low-elevationriparian habitats preferred by Bell’s vireos areuncommon in the assessment area. Conse-quently, Bell’s vireo numbers are low on na-tional forest system lands and make up a smallpercentage (less than 3 percent) of the totalregional population. The largest populationon national forest system lands, currentlytwenty to thirty pairs, is located on the LosPadres along the upper Santa Ynez River andits tributaries, Mono and Indian Creeks, aboveGibraltar Reservoir. This population has beenmonitored for many years by Jim Greaves andassociates (Gray and Greaves 1984; Greaves1989, 1993, 1997). It appears to be the onlyarea on the Los Padres where Bell’s vireos con-sistently breed (Greaves and Labinger 1997).

The other documented breeding locationswithin the assessment area are within or nearthe Cleveland National Forest. Bell’s vireo lo-cations on the Cleveland National Forest arealong the upper reaches of drainages that havesubstantially larger populations further down-stream. Small breeding populations (one to tenpairs) exist on national forest system landsalong Cottonwood Creek (a tributary of theTijuana River), Pine Valley Creek (a tributaryof Cottonwood Creek), Santa Ysabel Creek,and the San Luis Rey River.

Within the Angeles National Forest therehave been sporadic sightings of Bell’s vireosduring the breeding season on SanFrancisquito Creek, Big Tujunga Creek, andthe upper Santa Clara River (USFWS 1998c).Two were also sighted on Cajon Creek withinSan Bernardino National Forest in 1990.However, breeding has not been documentedat any of these locations. There is a need todetermine if breeding populations exist inthese drainages.

The decline of this species is attributedprimarily to extensive loss of low elevation ri-parian habitat and brood parasitism by the

brown-headed cowbird. In recent years, leastBell’s vireo numbers in southern Californiahave increased dramatically, from an estimated300 pairs in 1986 to an estimated 1,346 pairsin 1996 (USFWS 1998c).

Habitat: The least Bell’s vireo is aneotropical migrant that breeds in low-eleva-tion riparian habitats, particularly broadcottonwood-willow woodlands and mule fatscrub. A detailed description of habitat char-acteristics is provided in the draft recovery plan(USFWS 1998c).

Conservation Considerations: Within theassessment area, habitat degradation and nestparasitism by brown-headed cowbirds are thebiggest threats to least Bell’s vireos (USFWS1998c). Habitat loss is occurring primarily inurbanizing areas and is not considered to be amajor problem on public lands.

Cowbird nest parasitism, where it has notbeen effectively reduced through control pro-grams, is probably the most chronic anddebilitating threat to least Bell’s vireo popula-tions. It is considered to be a major problemfor all of the Bell’s vireo populations on na-tional forest system lands (Greaves 1997; Wellsand Turnbull 1998). Cowbird control effortsnear vireo breeding areas are cited as being par-ticularly instrumental in the recovery of thisspecies.

On the Santa Margarita River within theCamp Pendleton Marine Corps Base, cowbirdparasitism of least Bell’s vireo nests was at 47percent in 1983 when the base began an in-tensive cowbird trapping program. Withannual trapping, by 1990 the brood parasit-ism rate had dropped to less than 1 percent(Griffith and Griffith, in press). The SantaMargarita River Bell’s vireo population rosefrom 60 pairs in 1983 to 319 pairs in 1993(Griffith and Griffith, 1995). Since the initia-tion of annual cowbird removal programs,similarly dramatic population increases haveoccurred on the Tijuana and San Luis Rey riv-ers and in the Prado Basin (Kus 1995; Kus1996; Pike and Hays 1997).

Bell’s vireo populations on national forestsystem lands have not been nearly as success-ful. The Santa Ynez River population has

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Chapter 4dropped from fifty-five breeding pairs in 1980to fewer than thirty pairs in 1994 (Greaves1997). The population along Pine ValleyCreek has dropped from five pairs in 1994 tozero in 1997 and 1998, although in neigh-boring Cottonwood Creek the population hasstayed consistently around four to six pairs(Wells and Turnbull 1998).

Habitat degradation can occur when thestructure or composition of riparian vegeta-tion is altered. Dense shrub cover within 3 to6 feet of the ground is important for Bell’svireos and this cover can be significantly re-duced by overgrazing, off-road vehicle activity,concentrated recreation use, channel clearing,and large discharges of water from upstreamreservoirs. Invasions of non-native plants, par-ticularly arundo and tamarisk, are alsocrowding out native plants and degradinghabitats for the Bell’s vireo in a number of lo-cations.

Warbling vireo (Vireo gilvus)Status and Distribution: The warbling

vireo is identified as a high-priority riparianobligate species by California Partners in Flight(Evans 1997). It is a summer resident at low-to mid-elevations across the assessment area,although there are few recent breeding recordsfrom the San Jacinto Mountains and the SanDiego ranges (Garrett and Dunn 1981; Unitt1984).

Warbling vireos were detected at 30 per-cent of the riparian point-count stationsannually and they increased significantly inabundance between 1988 and 1996 (table 4.6)(Stephenson et al. 1998). However, the BBSresults suggest that warbling vireos may be de-clining statewide. Garrett and Dunn (1981)indicate that this species has declined in thesouthern half of the assessment area, particu-larly at lower elevations.

Habitat: In the northern part of the as-sessment area, warbling vireos commonly nestin low-elevation riparian and mixed woodlandhabitats (Garrett and Dunn 1981). In thesouth they apparently now nest primarily inmixed conifer-oak woodlands in the moun-tains (Garrett and Dunn 1981; Unitt 1984).

Conservation Considerations: Nest para-sitism by brown-headed cowbirds is stronglyimplicated in the decline of this species as abreeder in coastal lowland and foothill ripar-ian areas (Garrett and Dunn 1981; Unitt1984).

Yellow warbler(Dendroica petechia brewsteri)

Status and Distribution: The yellow war-bler is a California Species of Special Concernand is identified as a high-priority riparian ob-ligate species by California Partners in Flight(Evans 1997). It is a summer resident at low-elevations across the assessment area.

Yellow warblers were detected at 51 per-cent of the riparian point-count stationsannually and had a very stable trend. This wasthe only species for which it was possible toconclude, with high statistical power, that theyare not declining at an annual rate of 3 per-cent or more (table 4.6) (Stephenson et. al.1998). However, results from the BBS sug-gest that the yellow warbler may be decliningstatewide and in the California foothills physi-ographic region (Sauer et al. 1997).

Habitat: Yellow warblers breed in ripar-ian woodlands in the lowlands and foothillcanyons (Garrett and Dunn 1981; Unitt 1984;Lehman 1994). They are typically found inriparian forests that contain cottonwoods, sy-camores, willows, or alders.

Conservation Considerations: Nest para-sitism by brown-headed cowbirds is stronglyimplicated in the decline of this species as abreeder in coastal lowland and foothillriparian areas (Garrett and Dunn 1981; Unitt1984).

Common yellowthroat (Geothlypis trichas)Status and Distribution: The common

yellowthroat is identified as a high priority ri-parian obligate species by California Partnersin Flight (Evans 1997). It is primarily a spe-cies of lowland habitats and occurs in theassessment area only in the low foothills. Com-mon yellowthroats were detected at only 8percent of the riparian point-count stations

154

annually and no clear trend in abundancecould be ascertained (table 4.6). BBS resultssuggest that yellowthroats may be on the in-crease statewide (Sauer et al. 1997).

Habitat: Common yellowthroats typicallybreed in fresh water and brackish marshes ofcattails, bulrushes, and other emergent veg-etation and also occupy dense brush in dampareas (Garrett and Dunn 1981).

Conservation Considerations: The pri-mary threat to this species is loss or degradationof riparian habitats, particularly areas that sup-port dense emergent vegetation.

Yellow-breasted chat (Icteria virens)Status and Distribution: The yellow-

breasted chat is a California Species of SpecialConcern and is identified as a high-priorityriparian obligate species by California Partnersin Flight (Evans 1997). It is a localized sum-mer resident in low-elevation foothill canyonsacross the assessment area and appears to bequite rare. Indications are that this species hasdeclined dramatically in southern California(Garrett and Dunn 1981).

Chats were rarely detected in the riparianpoint-count survey. All of the stations at whichthey were detected in multiple years are lo-cated on the Los Padres National Forest.Known locations of the yellow-breasted chatinclude Mono Creek, Santa Ynez River, andSespe Creek on the Los Padres National For-est; San Francisquito and Elizabeth Lake can-yons on the Angeles National Forest; BautistaCanyon on the San Bernardino National For-est; and the upper San Luis Rey River on theCleveland National Forest (Unitt 1984).

Habitat: Yellow-breasted chats breed indense riparian thickets and brushy tangles inthe vicinity of water courses (Garrett andDunn 1981). They are found primarily in thecoastal lowlands.

Conservation Considerations: Majorthreats to this species are loss of lowland ri-parian habitat and nest parasitism by brown-headed cowbirds (Garrett and Dunn 1981).More information is needed on the distribu-tion and abundance of the yellow-breasted

chat within the assessment area. The rarity andapparent decline of this species warrants pay-ing increased attention to sites where they stilloccur.

Lawrence’s goldfinch (Carduelis lawrencei)Status and Distribution: The Lawrence’s

goldfinch has been identified as a “extremelyhigh priority” watch list species by Partners inFlight, although no reason is given for this des-ignation (Carter 1998). It is probably becausethe breeding range of this species is restrictedto California west of the Sierra Nevada and tonorthern Baja California. Lawrence’s gold-finches are found at low- to mid-elevations onboth coastal and desert sides of the assessmentarea, but it is described as an opportunistic,nomadic breeder (D. Cooper, UC Riverside,pers. comm.), and thus its distribution andabundance varies considerably from year toyear (Garrett and Dunn 1981).

Lawrence’s goldfinches were detected at 12percent of the riparian point count stationsannually and had a declining trend of 9.6 per-cent per year (table 4.6). However, this speciesis known for having large and erratic fluctua-tions in abundance (Garrett and Dunn 1981),so this trend may be misleading. A decline inLawrence’s goldfinches was not apparent instatewide BBS results, but was observed in BBSroutes from the Los Angeles Ranges physi-ographic region (Sauer et al. 1997).

Habitat: Lawrence’s goldfinches breedaround riparian thickets within arid wood-lands and shrublands (e.g., arid oak savanna,pinyon-juniper, chaparral, open coniferousforest) (Garrett and Dunn 1981).

Conservation Considerations: It is diffi-cult to assess the conservation needs of theLawrence’s goldfinch. More information isneeded on what areas or microhabitats maybe particularly important to this species.

Riparian Invertebrates

Three riparian invertebrates were identi-fied as being rare or potentially at risk and re-ceived individual consideration (table 4.9).

155

Chapter 4California diplectronan caddisfly(Diplectronan californica)

Status and Distribution: The Californiadiplectronan caddisfly is a former C2 candi-date for federal listing. Information is scarceon the range of this species; the type localityis from Claremont and the only other identi-fied location is on Mill Creek at Thurman Flatsin the San Bernardino National Forest (Ermanand Nagano 1992).

Habitat: Little is known about this par-ticular species, but other species of this genusare known to occur in rapid portions of small,cool streams (Erman and Nagano 1992).

Conservation Considerations: More in-formation is needed on the distribution, abun-dance, and habitat associations of this caddisflybefore a meaningful conservation strategy canbe developed.

InvertebratesCA diplectronan Very Low y p p Unkn Unkn Landscape caddisfly (?) level

Greenest tiger beetle Very Low p p Unkn Unkn Miinimal(?) Influence

Harbison’s dun skipper Mod y y Mod Unkn Landscape(< 20%) level

MammalsWestern red bat Low y y y y y y y y y Mod Unkn Landscape

(?) level

San Bernardino Low y y Low Unkn Landscape dusky shrew (> 75%) level

Ringtail Low y y y y y y y y y Low Unkn Landscape(30-70%) level

Greenest tiger beetle(Cicindela tranquebarica virudissima)

Status and Distribution: The greenest ti-ger beetle was formerly a C1 candidate spe-cies for federal listing. It is known from theupper Santa Ana River wash area at the baseof the San Bernardino Mountains (Ballmer1992) and was observed in Bautista Canyonin the 1970s (M. Nelson, USFWS, pers.comm.). It is unknown if these populationsextend onto public lands within the assessmentarea.

In 1996, the U.S. Fish and Wildlife Ser-vice removed this subspecies from thecandidate list based on taxonomic studieswhich indicate that C. t. virudissima is syn-onymous with the more widely distributed C.t. vibex (USFWS 1996b).

Habitat: The greenest tiger beetle is usu-ally found near running water where there isfine sand. Larvae live in burrows in the sandat the margin of streams. Adults are active

Riparian Mammalsand Invertebrates

federal status

(1)Knowledgeof SoCalLocations

(% on NFs)

(5)Conser-vation

Category

(4) Pop.Trend

(3)Vulner-ability

on NFs

(2) areas occupied or estimated # of occurrences if spp. localized

San Bern. NFCleveland NF Angeles NF Los Padres NFSan

DiegoRngs

SanJacMts

SntaAnaMts

SanBernMts

No.SL

Rng

So.SL

Rng

SanGabMts

Cas-taic

Rngs

So.LP

Rngs

Table 4.9. Riparian-associated invertebrates and mammals that received individual consideration.Displayed for each species: (1) the level of knowledge about where it occurs in southern California and, inparentheses, the estimated percentage of locations that are on national forest system lands; (2) the mountainsubareas occupied (y = occurs in breeding season, h = historically occurred, p = potentially occurs, t = transient,w = winter visitor)—if the species is localized and data are available, the approximate number of occurrences may bedisplayed; (3) the vulnerability of populations on national forest system lands to existing threat factors; (4)population trends; and (5) the assigned conservation category.

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Riparian Mammals

Three riparian-associated mammals wereidentified as being rare or potentially at riskand received individual consideration (table 4.9).

Western red bat (Lasiurus blossevillii)Status and Distribution: The western red

bat is a Forest Service Region 5 Sensitive Spe-cies and a California Species of SpecialConcern. There is little information on thedistribution and relative abundance of west-ern red bats in southern California. Duringsurveys in the national forests, it was recentlydetected by mist net capture or Anabat detec-tor in the following locations: upper SalinasRiver (Los Padres National Forest), SugarloafMeadows and Big Bear Dam (San BernardinoNational Forest), and Laguna Meadow andLost Valley (Cleveland National Forest)(Miner and Brown 1996; Simons et al. inprep.).

Habitat: The western red bat is primarilya solitary species that roosts in the foliage oftrees and shrubs often, but not exclusively, inriparian habitats (Bolster 1998).

Conservation Considerations: More in-formation is needed on the distribution andabundance of this species before its conserva-tion needs can be adequately assessed. Thereis a concern about the effect of controlledburns on this species when roosting in leaf lit-ter during cool weather (Bolster 1998).

San Bernardino dusky shrew(Sorex monticolus parvidens)

Status and Distribution: The San Bernar-dino dusky shrew was formerly a CaliforniaSpecies of Special Concern. It is reported tooccupy riparian habitats from about 4,200 to7,500 feet elevation in the San Bernardino andSan Gabriel mountains (Hennings andHoffman 1977). However, Williams (1986)reports that these shrews are indistinguishablefrom ornate shrews captured in the same ar-eas. He concludes that they are probably thesame species and that these populations arenot threatened.

runners and fliers along stream shores (Ballmer1992).

Conservation Considerations: Informa-tion is needed on the distribution of this beetlealong portions of the Santa Ana River andBautista Creek that lie within the assessmentarea. However, changes in the species’ tax-onomy suggest it is no longer a rare taxon.

Harbison’s dun skipper(Euphyes vestris harbisoni)

Status and Distribution: The Harbison’sdun skipper is a former C2 candidate for fed-eral listing. This butterfly occurs in a series ofscattered and disjunct colonies throughoutwestern San Diego County, extending as farnorth as the Santa Ana Mountains in OrangeCounty (Brown 1991). Localities in or nearthe assessment area include Silverado Canyon(Santa Ana Mountains), San Pasqual Valley,Ramona, Flinn Springs, Old Viejas Grade,Otay Mountain, and Tecate Peak (Murphy1990; Brown 1991). Some historic popula-tions have declined or been extirpated,primarily due to habitat loss resulting fromdevelopment.

Habitat: The Harbison’s dun skipper typi-cally occurs in partially-shaded, riparian oakwoodland habitats in a matrix of chamisechaparral or southern mixed chaparral, whereseeps or springs provide adequate water tosupport the larval host plant, San Diego sedge(Carex spissa) (Brown 1991). The butterfly hasnever been found in the absence of San Diegosedge (Brown 1991).

Conservation Considerations: More in-formation is needed on occurrences of thisspecies on public lands in the Santa AnaMountains and the San Diego ranges. Thepresence of San Diego sedge in considerablenumbers is a strong indicator of potential habi-tat for this species (Brown 1991). Watersources associated with occupied or potentialhabitat should be protected.

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Chapter 4

Bald Eagle (Haliaeetus leucocephalus)Status and Distribution: Bald eagle popu-

lations in the continental United States werefederally listed as threatened in 1978. How-ever, steady population increases nationwideculminated in a formal proposal on July 4,1999, to remove bald eagles from the threat-ened species list. Southern California isprimarily wintering habitat for bald eagles.Breeding has been confirmed only in a fewlocations in the northern part of the assess-ment area (i.e., Nacimiento Lake, San AntonioLake, and Cachuma Lake). However, a pairrecently attempted to nest near SilverwoodLake in the San Bernardino Mountains.

The largest wintering population in south-ern California is at Big Bear Lake in the SanBernardino Mountains, where twenty to thirtyeagles typically congregate from November toMarch. Most of the other large reservoirs inthe assessment area also support anywherefrom two to ten wintering eagles. In the SanBernardino Mountains, bald eagles have beenobserved moving between lakes during thewinter (R. Butler, Mountaintop District, pers.comm.).

Habitat: In the assessment area, baldeagles are usually found close to lakes and res-ervoirs where they feed on fish, coots, andwaterfowl (Garrett and Dunn 1981).

Conservation Considerations: There arehigh levels of human activity around many ofthe reservoirs in the assessment area where baldeagles spend the winter months. The eaglesare affected by this activity and can alter their

Habitat: These shrews are solitary, secre-tive animals that occupy moist soil, stumps,and logs in montane riparian and wet meadowareas (Ingles 1965; Zeiner et al. 1990).

Conservation Considerations: The rec-ommended change in the taxonomic status ofthe San Bernardino dusky shrew has caused itto be dropped from the California Species ofSpecial Concern list. The ornate shrew is wide-spread and, given its habitat requirements andlife history characteristics, it should not be par-ticularly vulnerable to land use activitiescurrently occurring on national forest systemlands.

Ringtail (Bassariscus astutus)Status and Distribution: The ringtail is

not on any concern lists and it is believed tobe relatively common (P. Collins, Santa Bar-bara Nat. Hist. Museum, pers. comm.). Weinclude it as a local viability concern becausethere is little recent, documented informationon its distribution or status in the assessmentarea. Vaughan’s (1954) report on mammals inthe San Gabriel Mountains says that ringtailswere present in San Gabriel Canyon, DaltonCanyon, Palmer Canyon, and San AntonioCanyon. There are more recent reports ofsightings in Lytle Creek Canyon (S. Loe, SanBernardino NF, pers. comm.).

Habitat: Ringtails are generally known tooccupy brushy and wooded areas along watercourses in foothill and lower montane can-yons (Jameson and Peeters 1988). Its principalhabitat requirements seem to be den sitesamong boulders or in hollows in trees andsufficient food in the form of rodents and othersmall animals (Williams 1986). Rocky habi-tats are apparently preferred. In the SanGabriel Mountains, Vaughan (1954) reportsthat ringtails occur in canyons in the chapar-ral belt. Unlike the raccoon, ringtailsreportedly avoid urbanized areas (Jameson andPeeters 1988).

Conservation Considerations: Some cur-rent, baseline information is needed on thedistribution of this species within the assess-ment area. However, the ringtail’s habitat

requirements are not likely to make it highlyvulnerable to land use activities occurringon national forest system lands.

Lake Species

Two species of concern, both birds, arestrongly associated with lake or reservoirhabitats (table 4.10). The distribution andabundance of these species has actually in-creased within the assessment area over thelast eighty years as a result of reservoir de-velopment.

158

Habitat: The Smith’s blue butterly occursin coastal prairie and coastal scrub habitats.Its distribution is limited to a portion of the

habitat use patterns because of it (Steidl andAnthony 1996).

Osprey (Pandion haliaetus)Status and Distribution: The osprey is a

California Species of Special Concern. It pri-marily is an uncommon winter visitor insouthern California, but nesting has beendocumented at Lake Casitas near Ventura andLake San Antonio in Monterey County(Garrett and Dunn 1981) and may occur else-where.

Habitat: Ospreys eat fish and thus arefound near large coastal estuaries and inlandlakes.

Conservation Considerations: The habi-tat requirements of osprey in the assessmentarea center on lake resources. Typically, theseresources are little affected by managementactivities occurring on national forest systemlands.

Animals of Monterey CoastHabitats

As described in chapter 2, the Montereycoast has habitats that are found nowhere elsein the assessment area. Ten animal species as-sociated with these unique habitats are con-sidered individually in this section (table 4.11).

Included in this group are two marine mam-mals and several bird species that are foundonly along the immediate coast. They requireconsideration because the Monterey Districtof the Los Padres National Forest encompassesalmost twenty miles of ocean coastline in thisarea.

Smith’s blue butterfly(Euphilotes enoptes smithi)

Status and Distribution: The Smith’s bluebutterfly was federally listed as endangered in1976. At the time of listing it was thought tooccur only in coastal dunes along MontereyBay and from coastal scrub near Big Sur (Fos-ter 1998). However, focused surveys haverevealed additional populations and theSmith’s blue is now known to occur along thecoastal portions of Monterey, Santa Cruz, andSan Mateo counties at about one hundred dif-ferent locations (R.A. Arnold pers. comm., ascited in Foster 1998). Eleven of these sites areon or close to national forest system land (Fos-ter 1998). Occupied areas include Big SurPark, Burns Creek, along the Nacimiento-Ferguson Road, Kirk Creek, and Gorda HorsePasture (fig. 4.16).

BirdsBald eagle High threatened* (30-60%) w t w w w w y y y Mod Stable Site

Specific

Osprey High w t w p/w t w y p/w y Mod Unkn Minimal(20-50%) Influence

Table 4.10. Rare or potentially at risk species associated primarily with lake habitats.Displayed for each species: (1) the level of knowledge about where it occurs in southern California and, inparentheses, the estimated percentage of locations that are on national forest system lands; (2) the mountainsubareas occupied (y = occurs in breeding season, h = historically occurred, p = potentially occurs, t = transient,w = winter visitor)—if the species is localized and data are available, the approximate number of occurrences may bedisplayed; (3) the vulnerability of populations on national forest system lands to existing threat factors; (4)population trends; and (5) the assigned conservation category.

* There is now a formal proposal to remove the bald eagle from the threatened species list.

Lake AssociatedAnimals of Concern

federal status

(1)Knowledgeof SoCalLocations

(% on NFs)

(5)Conser-vation

Category

(4) Pop.Trend

(3)Vulner-ability

on NFs

(2) areas occupied or estimated # of occurrences if spp. localized

San Bern. NFCleveland NF Angeles NF Los Padres NFSan

DiegoRngs

SanJacMts

SntaAnaMts

SanBernMts

No.SL

Rng

So.SL

Rng

SanGabMts

Cas-taic

Rngs

So.LP

Rngs

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Chapter 4

InvertebratesSmith’s blue butterfly High y Mod Unkn Site endangered (10-50%) specific

Doudoroff’s elfin Low y Low Unkn Landscape(40-80%) level

Clemence’s silverspot Mod y y Low Unkn Landscape(40-80%) level

AmphibiansPacific giant Low y Low Unkn Landscape salamander (40-80%) level

BirdsCA brown pelican High y Low Incr Minimal endangered (<2%) Influence

Western snowy plover Mod p Mod Unkn Site threatened (< 2%) specific

Marbled murrelet Mod y Low Unkn Site endangered (< 5%) specific

MammalsMonterey dusky-footed Low y Low Unkn Landscape woodrat (?) level

Southern sea otter High y Low Stable Minimal threatened (< 1%) Influence

Steller sea lion High y Low Decl Minimal threatened (< 5%) Influence

Monterey CoastAnimals of Concern

federal status

(1)Knowledgeof SoCalLocations

(% on NFs)

(5)Conser-vation

Category

(4) Pop.Trend

(3)Vulner-ability

on NFs

(2) areas occupied or estimated # of occurrences if spp. localized

San Bern. NFCleveland NF Angeles NF Los Padres NFSan

DiegoRngs

SanJacMts

SntaAnaMts

SanBernMts

No.SL

Rng

So.SL

Rng

SanGabMts

Cas-taic

Rngs

So.LP

Rngs

Table 4.11. Animals associated with Monterey Coast habitats that received individual consideration.Displayed for each species: (1) the level of knowledge about where it occurs in southern California and, inparentheses, the estimated percentage of locations that are on national forest system lands; (2) the mountainsubareas occupied (y = occurs in breeding season, h = historically occurred, p = potentially occurs, t = transient,w = winter visitor)—if the species is localized and data are available, the approximate number of occurrences may bedisplayed; (3) the vulnerability of populations on national forest system lands to existing threat factors; (4)population trends; and (5) the assigned conservation category.

combined range of two host plants: seacliffbuckwheat (Eriogonum parvifolium) and coastbuckwheat (Eriogonum latifolium). Togetherthese two plants function as the sole larval andprimary adult food plants for the butterfly(Arnold 1983). Norman (1994) surveyed thewest slope of the northern Santa Lucia Rangeand, based on the presence of seacliff buck-wheat, estimated that there are several thou-sand acres of potentially suitable Smith’s bluebutterly habitat on the Monterey Ranger Dis-trict. The elevation range of seacliff buckwheat

is from sea level to approximately 2,600 feet(Foster 1998).

Conservation Considerations: TheSmith’s blue butterfly is a rare and highly lo-calized species that warrants site-specificmanagement attention. Foster (1998) providesa detailed evaluation of factors potentially af-fecting Smith’s blue butterfly populationswithin the assessment area; the following syn-opsis is based on that report. Small amountsof suitable habitat may be affected by existingroads, trails, and developed recreation sites.

160

Figure 4.16. Documented locations of the Smith’s blue butterfly along the Monterey coast (this map may notshow all known localities).

1990). Potential habitat occurs elsewhere alongthe southern Monterey coast, primarily on theLos Padres National Forest east of Highway 1and largely within the Ventana WildernessArea. The lack of observations of this speciesfrom other areas is attributed to the inaccessi-bility of its habitat and its short, early flightperiod (February to early March) (Murphy1990).

Habitat: The host plant for Doudoroff ’selfin is a Sedum species (Murphy 1990).

Conservation Considerations: Additionalinformation is needed on the distribution andabundance of this species and its host plant.In Murphy’s (1990) status review, the

able and occupied Smith’s blue habitat andmay be causing habitat degradation. Invasive,non-native plants may be causing a reductionin the abundance of seacliff buckwheat. Par-ticular problem species are kikuyu grass(Pennisetum clandestinum), Pampas grass, andFrench broom.

Doudoroff’s elfin butterfly(Incisalia mossii doudoroffi)

Status and Distribution: The Dou-doroff ’s elfin butterfly is known primarily fromPartington Canyon near Big Sur (Murphy

Livestock grazing is permitted in areas of suit-

161

Chapter 4Doudoroff ’s elfin is listed as a category Ctaxon, that is, a taxon for which specific pro-tective measures are not presently necessary.However, it appears this determination is basedupon very little specific information.

Clemence’s silverspot butterfly(Speyeria adiaste clemencei)

Status and Distribution: The Clemence’ssilverspot butterfly occurs in both the north-ern and southern Santa Lucia Ranges, fromthe vicinity of Carmel on the north, to thearea of Pozo on the south (Murphy 1990). Itis also found on the north end of GarciaMountain. Much of its distribution is believedto be on the Los Padres National Forest(Murphy 1990).

Habitat: The suspected food plant of thisbutterfly is Viola quercetorum (Murphy 1990).

Conservation Considerations: Additionalinformation is needed on the distribution andabundance of this species. Murphy (1990)considers the Clemence’s silverspot to be a cat-egory D taxon, that is, a taxon that is neitherin danger of extinction nor likely to be. How-ever, it is unclear what specific information isbeing used to make this determination.

Pacific giant salamander(Dicamptodon ensatus)

Status and Distribution: The northernSanta Lucia Range contains the southernmostpopulations of this salmander (Anderson1969). This disjunct population is concen-trated along the Little Sur River (J. Copp, CAAcademy of Sciences, pers. comm.). We didnot find any information on the abundanceor status of the Pacific giant salamander in thisarea. It is not considered to be a sensitive spe-cies.

Habitat: The Pacific giant salamander isassociated with streams and other mesic habi-tats in humid, coastal forests (particularlyredwood).

Conservation Considerations: Waterquality and the sustainability of mesic condi-tions appear to be important factors for thePacific giant salamander. Along the Monterey

coast, much of the habitat for this species iswithin a designated wilderness area.

California brown pelican(Pelecanus occidentalis californicus)

Status and Distribution: The federally en-dangered California brown pelican is foundonly near the ocean, along the entire centraland southern California coast and in BajaCalifornia, Mexico (Garrett and Dunn 1981).It is addressed as a Monterey coast species be-cause that is the only place where theassessment area reaches the ocean’s edge. Ap-proximately twenty miles of coastline arewithin the Monterey District of the Los Pa-dres National Forest. Brown pelicans are notbelieved to breed along this stretch, but theycan be found there during the summermonths.

Habitat: The California brown pelican isalmost exclusively a bird of marine habitatsand thus is found only along the immediatecoastline. Birds currently nest in several largecolonies on the Channel Islands (Garrett andDunn 1981).

Conservation Considerations: The pri-mary threats to brown pelicans are (1) thecontinued, although dwindling, presence oforganochlorine pesticides (e.g., DDT) in themarine food chain, and (2) depleted foodresources due to commercial harvesting of fishsuch as anchovies (Garrett and Dunn 1981).However, brown pelican numbers have in-creased substantially in the last twenty years.This increase has largely been attributed to adecline in near-shore DDT levels.

Although the brown pelican does occuron public lands within the assessment area,the management of those lands has little ef-fect on the conservation of this species. Brownpelicans are dependent on resources that comefrom the marine environment and on the keylocations where they nest.

Western snowy plover(Charadrius alexandrinus nivosus)

Status and Distribution: The westernsnowy plover is primarily an inhabitant of

162

sandy coastal beaches. It was federally listedas threatened in 1993 because of populationdeclines and disturbance to coastal nesting sites(USFWS 1993d). The preference of snowyplovers for sandy beaches has led to its declineas a nesting bird along the coast; such areassuffer from much human disturbance duringthe nesting season (Garrett and Dunn 1981).Snowy plovers reportedly nest on the beachnear Point Sur Lighthouse just north of theassessment area (California Coastal Commis-sion 1987). Most of the coastline within theassessment area is steep and devoid of sandybeaches; however, there are several smallbeaches (e.g., Pfeiffer and Sand Dollar) thatpotentially could support this species.

Habitat: Snowy plovers nest, feed, andtake cover on sandy or gravelly beaches alongthe coast, on estuarine salt ponds, and on al-kali lakes (Zeiner et al. 1990a).

Conservation Considerations: More in-formation is needed on the nesting status ofsnowy plovers in this area and the potentialfor beaches within the assessment area to sup-port nesting.

Marbled murrelet(Brachyramphus marmoratus)

Status and Distribution: The marbledmurrelet was federally listed as threatened in1992 because of population declines and con-cerns that logging in coastal forests of the PacificNorthwest was eliminating its nesting habitat(USFWS 1992b). The Monterey coast is at theextreme southern periphery of the marbledmurrelet’s breeding range (Ralph et al. 1995).

Reported sitings of marbled murreletsalong the central California coast have beenconcentrated within a 6-mile (10 kilometer)radius of Point Año Nuevo in Santa CruzCounty (Ainley et al. 1995). It is unclear ifthey actually do nest as far south as the coastalforests in the northern Santa Lucia Range. Thehabitat appears suitable, but we could find nodocumentation of sitings in this area.

Habitat: Marbled murrelets spend mostof their lives at sea but come onshore to nestin large, old trees. They are highly secretive

on land and it is difficult to locate their nestsites (Ralph et al. 1995).

Conservation Considerations: It is impor-tant to determine if marbled murrelets do nestin the northern Santa Lucia Range. How-ever, even if they do, threats to suitablebreeding habitats are likely to be low. Nologging is done in this area and most of theforested area along the immediate coast iswithin state parks or Forest Service wilder-ness areas.

Monterey dusky-footed woodrat(Neotoma fuscipes luciana)

Status and Distribution: The Montereydusky-footed woodrat is listed as a CaliforniaSpecies of Concern although it was not dis-cussed in Williams’ (1986) report onmammalian species of concern in California.We could find very little information on thisspecific subspecies, other than it is reportedto occur in a variety of areas on Fort Ordnear Monterey. Woodrats are common inthe northern Santa Lucia Range (e.g., theHastings Reserve) (Williams et al. 1992),but it is unclear if they are this particularsubspecies.

Habitat: Dusky-footed woodrats are gen-erally found in dense chaparral, oak and ri-parian woodland, and in mixed conifer forestthat has a well-developed understory. Theyseem to favor brushy habitat or woodland thathas a live oak component. They are highly ar-boreal, and thick-leaved trees and shrubs areimportant habitat components for this spe-cies (Williams et al. 1992).

Conservation Considerations: Clarifica-tion is needed on whether woodrats occurringin the northern Santa Lucia Range are N. f.luciana. There is a large amount of suitablewoodrat habitat in these mountains and it isnot considered to be threatened by existingland uses or ecological changes.

Southern sea otter (Enhydra lutris nereis)Status and Distribution: Coastal waters

from the Carmel River south to Santa RosaCreek have been designated as the California

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Chapter 4Sea Otter State Game Refuge. Sea otters arecommon along this stretch of coastline.

Habitat: Sea otters spend essentially theirentire life in shallow ocean waters, particularlyin the vicinity of kelp beds. They occur nearland in protected coves and shallow intertidalwaters but rarely, if ever, venture onshore.Abalone and urchins are their preferred food.

Conservation Considerations: Activitiesoccurring on the Los Padres National Forestand other public lands within the assessmentarea are unlikely to have any effect on sea ot-ters. The primary threats to this species, asidentified on the Friends of the Sea Otter webpage, are offshore oil spills and competitionfrom humans for abalone.

Steller sea lion (Eumetopias jubatus)Status and Distribution: The central Cali-

fornia coast is the southern limit of the Stelleror northern sea lion’s range. Historically therewas a rookery on San Miguel Island, one ofthe Channel Islands, but the last pups wereborn there in 1982 (Marine Mammal Center1997). The southernmost active rookery is onAño Nuevo Island in San Mateo County.Steller sea lions are declining precipitously andare now rare along the Monterey coast.

Habitat: The Steller sea lion is a marinemammal that forages near shore. It does haulout on mainland coastlines but more com-monly utilizes offshore rocks (MarineMammal Center 1997).

Conservation Considerations: Activitiesoccurring on the Los Padres National Forestand other public lands within the assessmentarea are unlikely to have any significant effecton the status of this species.

Animals of Low-Elevation ValleyHabitats

Sixteen of the animal species that receivedindividual consideration are associated withlow-elevation valley habitats (table 4.12). Sixspecies are either restricted to or primarilyfound in the vicinity of the San Joaquin Val-ley, six are found strictly in valleys on thecoastal side of the mountains, and four occur

Western San Joaquin Valley InhabitantsLonghorn fairy shrimp(Branchinecta longiantenna)

Status and Distribution: The longhornfairy shrimp was federally listed as endangeredin 1994. It occurs primarily along the westside of the San Joaquin Valley from AltamontPass south to the Carrizo Plain (Eng et al.1990). There are no known localities withinthe assessment area; the closest is at Soda Lake.There is some potential for the species to oc-cur in potrero habitats in the Sierra MadreMountains.

Habitat: These small crustaceans inhabitrain-filled, ephemeral pools (i.e., vernal pools)that form in depressions usually in grasslandhabitats (Eng et al. 1990). These pools mustfill frequently enough and persist long enoughfor the fairy shrimp to complete their life cycle.

Conservation Considerations: Surveys areneeded to determine if this species occurs onpublic lands within the assessment area.

Blunt-nosed leopard lizard (Gambelia silus)Status and Distribution: The blunt-nosed

leopard lizard was federally listed as endan-gered in 1967. It is endemic to the San JoaquinValley and surrounding foothills. Its distribu-tion overlaps the assessment area only in theupper Cuyama Valley, where it approaches theLos Padres National Forest. This region is sig-nificant from an evolutionary perspectivebecause it is a contact zone between the blunt-nosed leopard lizard and the long-nosedleopard lizard (Gambelia wislizenii), a speciescommon in the Mojave Desert (Montanucci

on both sides of the mountains. Low-eleva-tion valley habitats are primarily outside theassessment area and poorly represented onnational forest system lands. Consequently, theability to influence the conservation of thesespecies through management of national for-est system lands is often small. However, theyhave the potential to occur within the assess-ment area in a few localized areas so they needto be considered.

Low-Elevation ValleyAnimals of Concern

federal status

(1)Knowledgeof SoCalLocations

(% on NFs)

(5)Conser-vation

Category

(4) Pop.Trend

(3)Vulner-ability

on NFs

(2) areas occupied or estimated # of occurrences if spp. localized

San Bern. NFCleveland NF Angeles NF Los Padres NFSan

DiegoRngs

SanJacMts

SntaAnaMts

SanBernMts

No.SL

Rng

So.SL

Rng

SanGabMts

Cas-taic

Rngs

So.LP

Rngs

Table 4.12. Animals associated with low-elevation valley habitats that received individualconsideration. Displayed for each species: (1) the level of knowledge about where it occurs in southern Californiaand, in parentheses, the estimated percentage of locations that are on national forest system lands; (2) themountain subareas occupied (y = occurs in breeding season, h = historically occurred, p = potentially occurs,t = transient, w = winter visitor)—if the species is localized and data are available, the approximate number ofoccurrences may be displayed; (3) the vulnerability of populations on national forest system lands to existing threatfactors; (4) population trends; and (5) the assigned conservation category.

West. San Joaquin Val.

Longhorn fairy shrimp Mod p Unkn Unkn Minimal endangered (0%) influence

Blunt-nosed leopard High h/phy Low Decl1 Minimal lizard endangered (< 1%) influence

Mountain plover Mod w w Decl2 Minimal C1 candidate (0%) influence

Giant kangaroo rat Mod p p Low Decl1 Minimal endangered (0%) influence

San Joaquin antelope High p p Low Unkn Minimal squirrel (< 1%) influence

San Joaquin kit fox High p p Low Decl1 Minimal endangered (< 2%) Influence

Coastal Valleys

CA tiger salamander Mod p p y Mod Decl3 Site(< 5%) Specific

L.A. pocket mouse Low p p h/p p Low Minimal (< 2%) Influence

Pacific pocket mouse Mod p p Low Decl1 Minimal endangered ( 0%) influence

San Bern. kangaroo rat Mod y p Low Decl1 Site endangered (< 3%) specific

Stephens’ kangaroo rat High y p p Low Decl1 Landscape endangered (< 1%) level

San Diego black-tailed Mod y p p y h/p Low Unkn Landscape jackrabbit (< 5%) level

Both

Vernal pool fairy shrimp High y y p Mod Unkn Landscape threatened (< 5%) level

Burrowing owl Mod p p p h/p p Mod Decl2 Minimal(< 1%) Influence

Swainson’s hawk Mod t t t t t p p p t Low Decl2 Minimal(< 5%) influence

Loggerhead shrike Mod y y y y p y y y p Low Unkn Landscape(< 5%) level

hy Hybrid population (Gambelia silus x G. wislizenii)1 USFWS determination as described in Final Rule to list as endangered.2 Garrett and Dunn (1981); Zeiner et al. (1990); Lehman (1994)3 Jennings and Hayes (1994)

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Chapter 4habitats in the Los Padres National Forest toany significant extent. Thus, it appears thereis little potential to influence the conservationof mountain plovers through management ofnational forest system lands within the assess-ment area.

Giant kangaroo rat (Dipodomys ingens)Status and Distribution: The giant kan-

garoo rat was federally listed as endangered in1987. It inhabits the arid southwestern edgeof the San Joaquin Valley, the Carrizo andElkhorn plains, and the Cuyama Valley (Wil-liams 1992). It occurs at elevations rangingfrom approximately 280 to 2,800 feet but israre above 2,400 feet (Williams 1996). Thegiant kangaroo rat’s range approaches, andpotentially extends onto, the Los Padres Na-tional Forest at the lower end of the CuyamaValley (fig. 4.17). We did not find any docu-mented sightings of this species on nationalforest system lands.

1978). Patterns of hybridization in this areaare of scientific interest and have providedinsights into the selective factors that main-tain two distinct species (Montanucci 1970;Montanucci 1978). There are no known oc-currences of the full species G. silus on theLos Padres; however, the narrow zone whereG. silus x G. wislizenii hybrids have beenfound is partially on national forest systemlands in the lower parts of Ballinger andQuatal canyons.

Habitat: The blunt-nosed leopard lizardinhabits semi-arid, sparsely vegetated grass-lands and dry washes (Montanucci 1970).

Conservation Considerations: Jennings(1995) reports that habitat loss in the zone ofhybridization may have eliminated the hybridpopulations studied by Montanucci. Surveywork is needed to conclusively determine ifhybrid blunt-nosed leopard lizards still occuron the Los Padres. If they do still occur, ef-forts should be made to protect thesepopulations because of their significance.However, conservation of the full species G.silus will be minimally influenced by man-agement of public lands within theassessment area.

Mountain plover (Charadrius montanus)Status and Distribution: The mountain

plover is proposed for federal listing as threat-ened and is a California Species of SpecialConcern. It winters in sparsely vegetated fieldsand grasslands at low elevations in southernCalifornia. Mountain plovers have becomevery rare on the coastal side of the mountains,although small wintering populations may stilloccur just west of Santa Maria (Lehman 1994)and in the Tijuana River Valley (Unitt 1984).The primary wintering ground near the as-sessment area is on the Carrizo Plain insoutheastern San Luis Obispo County (Knopfand Rupert 1995).

Habitat: Wintering mountain plovers ap-parently prefer alkaline flats, cultivated andplowed fields, and sparse grasslands.

Conservation Considerations: The studyby Knopf and Rupert (1995) suggests thatwintering mountain plovers do not utilize

Habitat: Giant kangaroo rats mainly in-habit sandy-loam soils located on level andgently sloping ground vegetated with annualgrasses and forbs and widely scattered desertshrubs. Long-term occupancy of a site by gi-ant kangaroo rats results in a mima-moundtopography, with burrow systems located onmounds a few to several centimeters above theintervening ground (Williams 1996).

Conservation Considerations: Additionalsurvey work is needed to conclusively deter-mine if the giant kangaroo rat extends ontothe Los Padres. If found, those areas shouldreceive site-specific management attention.However, it is likely that any occurrences onnational forest system lands will be at the fringeof suitable habitat which is concentrated inthe valley below. Thus management of publiclands within the assessment area will likelyhave minimal influence on the conservationof giant kangaroo rats.

San Joaquin antelope squirrel(Ammospermophilus nelsoni)

Status and Distribution: The San Joaquinantelope squirrel is state listed as threatened.

166

Figure 4.17. The documented locations of the giant kangaroo rat and San Joaquin antelope squirrel..

It occurs in the San Joaquin Valley and onslopes and ridgetops in the foothills along thewestern edge of the valley, in the Cuyama andPanoche valleys, and on the Carrizo andElkhorn plains (Best et al. 1990). The ante-lope squirrel’s range approaches, andpotentially extends onto, the Los Padres Na-tional Forest along the upper margins of theCuyama Valley (fig. 4.17). We did not findany documented sightings of this species onnational forest system lands.

Habitat: San Joaquin antelope squirrelsinhabit arid grassland, shrubland, and alkalisink habitats and are often found in associa-tion with saltbush (Atriplex) and Mormon tea

(Ephedra) (Best et al. 1990). Present popula-tions range in elevation from approximately100 feet to 3,600 feet (Brown and Williams1996).

Conservation Considerations: Same asthose described for the giant kangaroo rat.

San Joaquin kit fox(Ammospermophilus nelsoni)

Status and Distribution: The San Joaquinkit fox was federally listed as endangered in1967. It formerly occupied most of the SanJoaquin Valley as well as low-elevation basinsand ranges along the eastern side of the cen-tral Coast Ranges (Brown et al. 1997). Kit

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Chapter 4foxes potentially occur within the Los PadresNational Forest in the upper Cuyama Valleywatershed and along the eastern slope of theLa Panza Range. The species is most likely atransitory visitor on national forest systemlands, since there is little high-quality habitat.

Habitat: The San Joaquin kit fox prima-rily inhabits arid grasslands and openscrublands. It also will utilize oak savanna andalkali sink habitats (McGrew 1979).

Conservation Considerations: Additionalsurvey work is needed to determine the ex-tent to which kit foxes utilize areas within theLos Padres National Forest. Occupied areasshould receive site-specific management atten-tion. However, it seems apparent that nationalforest system lands are on the fringe of suit-able habitat; thus, management of public landswithin the assessment area will likely haveminimal influence on the conservation of thisspecies.

Coastal Valley InhabitantsCalifornia tiger salamander(Ambystoma californiense)

Status and Distribution: The Californiatiger salamander is a California Species of Spe-cial Concern. The known range of this speciesextends into the assessment area from thenorthern Santa Lucia Range south to the SantaYnez River. Based on the distribution map inJennings and Hayes (1994), tiger salamandersoccur in upper portions of the Carmel Riverand Little Sur River watersheds where they areeither on or near the Los Padres NationalForest.

No localities are shown in the southernSanta Lucia Mountains, but they do occur inthe lower Sisquoc River and Santa Ynez Riverwatersheds. These southernmost localities ap-pear to correspond with the Solomon Hillsand Santa Rita Hills, respectively, where SamSweet (pers. comm.) has found tiger sala-manders. Both of these locations are west ofthe Los Padres National Forest by at least 5miles. It is uncertain to what extent potentialhabitat is available on national forest systemlands.

Habitat: The California tiger salamanderis a lowland species restricted to grasslands andlow foothill regions where its breeding habi-tat (long-lasting rain pools) occurs. Permanentaquatic sites are unlikely to be used for breed-ing unless they lack fish predators (Shaffer etal. 1993; Jennings and Hayes 1994). Tigersalamanders also appear to require dry-seasonrefuge sites (typically small mammal burrows)in the vicinity of breeding sites (up to one mileaway) (Jennings and Hayes 1994). The knownelevational range of this species extends fromnear sea level to 3,400 feet (Shaffer et al. 1993).

Conservation Considerations: Californiatiger salamanders are dependent on the integ-rity of large rain pool complexes. Effortsshould be made to identify such potentialbreeding sites on the Los Padres National For-est, beginning with the upper Carmel Riverand Little Sur River watersheds where thisspecies is known to occur. Efforts should bemade to keep tiger salamander breeding sitesfree of non-native predators (e.g., fish, bull-frogs, and crayfish). This may requirecoordination with agencies in charge of mos-quito abatement to avoid the stocking ofmosquitofish in these areas (Jennings andHayes 1994).

Los Angeles pocket mouse(Perognathus longimembris brevinasus)

Status and Distribution: The Los Ange-les pocket mouse is a Forest Service Region 5Sensitive Species and a California Species ofConcern. The known range of this subspeciesextends from the cities of Burbank and SanFernando on the northwest, to the city of SanBernardino on the northeast, to the vicinityof Cabazon, Hemet, and Aguanga on the eastand southeast. Its geographic limits on thesouthwest are unclear but probably lie some-where near the Hollywood Hills (Williams1986). Bond (1977) identifies specimens fromRanchita and Warner Pass in San DiegoCounty as this subspecies, but Williams (1986)believes they are probably P. l. internationalis.

The geographic range just described is al-most entirely outside our assessment area.

168

Stephens’ kangaroo rat(Dipodomys stephensi)

Status and Distribution: The Stephens’kangaroo rat was federally listed as endangeredin 1988. It is known only from arid grassland

However, one historic Los Angeles pocketmouse locality listed in Williams (1986) is atDos Palmas Spring at the base of the SantaRosa Mountains, well to the east of the de-scribed range and within the San JacintoDistrict of the San Bernardino National For-est. Historic localities near Cabazon, Banning,Valle Vista, and Cajon Wash are close to na-tional forest system lands, although thetransition to steep, low-quality habitat occursrapidly in these areas.

Habitat: The Los Angeles pocket mouseoccupies areas with fine, sandy soils, typicallyin arid grassland or coastal sage scrub habitats(Genoways and Brown 1993). The upper el-evation limit of distributional records listedin Williams (1986) is 3,500 feet (at DosPalmas Spring), but most locations (all buttwo) are below 2,200 feet.

Conservation Considerations: Althoughthe potential for major populations is low,surveys are needed to determine if the LosAngeles pocket mouse occurs on public landswithin the assessment area. At a minimum theDos Palmas Spring location should be resur-veyed to see if this subspecies is present.National forest system lands in Cajon Washmay also contain potential habitat. However,given its known distribution and habitat re-quirements, this is a species whoseconservation is not likely to be significantlyinfluenced by management of national forestsystem lands within the assessment area.

Pacific pocket mouse(Perognathus longimembris pacificus)

Status and Distribution: The Pacificpocket mouse was federally listed as endan-gered in 1994. This taxon is endemic to theimmediate coast of southern California fromMarina del Rey and El Segundo in Los Ange-les County south to the vicinity of the Mexicanborder in San Diego County (Williams 1986).All known locations have been within 2.5miles of the coast and below 600 feet in eleva-tion (USFWS 1994c). Given this geographicrange, it is highly unlikely that the Pacific pocketmouse occurs within the assessment area.

Habitat: The habitat requirements of thisspecies are not well understood, but it is knownto occur in sparsely vegetated areas on fine-grain, sandy substrates in the immediatevicinity of the Pacific Ocean (USFWS 1994c).

Conservation Considerations: All indica-tions are that the Pacific pocket mouse is aspecies whose conservation cannot be influ-enced by management of national forestsystem lands within the assessment area.

San Bernardino kangaroo rat(Dipodomys merriami parvus)

Status and Distribution: The San Bernar-dino kangaroo rat was federally listed asendangered in 1998. The historical range ofthis subspecies extends from the San Bernar-dino Valley in San Bernardino County toMenifee Valley in Riverside County (USFWS1998e). Extant populations along lower LytleCreek and Cajon Wash extend into the assess-ment area and may extend into the SanBernardino National Forest (fig. 4.18). A largepopulation along the Santa Ana River extendsupstream to Greenspot Road bridge(McKernan 1997), which is less than a milebelow the San Bernardino National Forestboundary.

Habitat: San Bernardino kangaroo rats arefound primarily on sandy loam substrates,characteristic of alluvial fans and flood plains,where they are able to dig simple, shallowburrows (McKernan 1997). Vegetation inthese areas is typically alluvial sage scrub orchaparral.

Conservation Considerations: Additionalinformation is needed on the distribution ofSan Bernardino kangaroo rats on public landswithin the assessment area. Threats to its habi-tat include disruption of the natural hydrologicregime and habitat degradation due to a vari-ety of factors (e.g., sand and gravel mining,stream channelization, and vehicular traffic).

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Chapter 4

Figure 4.18. The approximate geographic ranges of the San Bernardino and Stephens kangaroo rats.

habitats in northern San Diego County, west-ern Riverside County, and the southwesternedge of San Bernardino County (fig. 4.18)(Bleich 1977). Known locations within the as-sessment area are all in San Diego County andinclude the Warner Springs/Lake Henshawarea (O’Farrell 1986), the Guejito Valley, andSanta Maria Valley. The only location wherethe Stephens’ kangaroo rat may actually occuron national forest system lands is along thenorthern edge of the Warner Springs/LakeHenshaw area, where suitable habitat extendsonto the Cleveland National Forest.

Habitat: Stephens’ kangaroo rats inhabitsparse grassland habitats, in areas with pen-etrable soils and flat to moderately slopingtopography. These areas include the base ofhillsides, flat areas along ridgetops, sandy

washes, and open fields (O’Farrell and Uptain1989). In addition, Stephens’ kangaroo ratsalmost always occupy habitats in which at leasthalf of the soil is bare during the summer andfall.

Conservation Considerations: This is aspecies whose conservation is not significantlyinfluenced by management of national forestsystem lands within the assessment area. Thesmall amount of Stephens’ kangaroo rat habi-tat that extends onto the Cleveland NationalForest is not threatened by existing activities.The area is grazed by livestock, but this activ-ity is widely believed to be conducive tomaintaining suitable habitat for this species.

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San Diego black-tailed jackrabbit(Lepus californicus bennettii)

Status and Distribution: The San Diegoor coastal black-tailed jackrabbit is a Califor-nia Species of Special Concern. Black-tailedjackrabbits are abundant in the deserts, but L.c. bennettii occurs only on the coastal side ofthe southern California mountains where suit-able jackrabbit habitat is less common. Mostof the historic habitat for this subspecies haseither been developed or converted to agri-culture. Vaughan (1954) found black-tailedjackrabbits to be “plentiful” in the coastal sagebelt along the base of the San Gabriel Moun-tains from Cajon Wash west to San GabrielCanyon. However, the landscape in that areahas changed dramatically since the early 1950sand the status of jackrabbit populations theretoday is unknown. In recent years, Steve Loe(San Bernardino NF, pers. comm.) has ob-served jackrabbits near the Del Rosa FireStation at the base of the San BernardinoMountains.

Bond (1977) provides locality informationfor a number of museum specimens collectedin San Diego County. Specimens were col-lected at elevations ranging from sea level to6,000 feet. Most San Diego County localitieswere west of the assessment area, but speci-mens were reported from Santa Ysabel and theLaguna and Cuyamaca mountains. Themountain localities are curious since they seemto be outside of traditional habitat and jack-rabbits are not seen in these areas today.

Habitat: Black-tailed jackrabbits are foundonly in open or semi-open country, typicallyin grasslands or sparse coastal scrub (Bond1977). They are not generally found in chap-arral or woodland habitats. Vaughan (1954)found them in “thin stands” of coastal sagescrub and on the margins of citrus groves inthe lower foothills of the San Gabriel Moun-tains.

Conservation Considerations: Informa-tion is needed on the current distribution ofSan Diego black-tailed jackrabbits on publiclands along the coastal slopes of the SanGabriel, San Bernardino, and San Jacinto

mountains and the mountains of San DiegoCounty. Activities currently occurring on pub-lic lands within the assessment area probablyare not a substantial threat to jackrabbits, butit is not clear if viable populations exist in theseareas which are on the edge of this species’historic range.

Inhabitants of Both Coastal andSan Joaquin ValleysVernal pool fairy shrimp(Branchinecta lynchi)

Status and Distribution: The vernal poolfairy shrimp was federally listed as threatenedin 1994. Most known locations are in the Sac-ramento and San Joaquin valleys, and alongthe eastern margin of the central Coast Ranges(e.g., Soda Lake). However, vernal pool fairyshrimp also occur inside the assessment areain two locations: (1) several small potreros inthe mountains north of Santa Barbara and (2)on the Santa Rosa Plateau along the south-eastern flank of the Santa Ana Mountains (Enget al. 1990).

Habitat: These small crustaceans inhabitrain-filled, ephemeral pools (i.e., vernal pools)that form in depressions usually in grasslandhabitats (Eng et al. 1990). These pools mustfill frequently enough and persist long enoughfor the fairy shrimp to complete their life cycle.

Conservation Considerations: Reportedoccurrences of vernal pool fairy shrimp in themountains north of Santa Barbara appear tobe within the Los Padres National Forest. Thevernal pools which support these populationsshould be identified and managed to main-tain their integrity and natural hydrologicregime. Pools on the Santa Rosa Plateau areprotected within an ecological reserve that ismanaged by The Nature Conservancy andRiverside County. There is little potential habi-tat for fairy shrimp on national forest systemlands in the Santa Ana Mountains.

Burrowing owl(Athene cunicularia hypogaeae)

Status and Distribution: The burrowingowl is a California Species of Special Concern.Burrowing owl populations are declining

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Chapter 4across much of their range (Haug et al. 1993)as habitat destruction and improper use ofpesticides affect chick survivorship and dis-persal (Winchell 1994). Once widespread,their distribution on the coastal side of themountains is now highly localized and frag-mented.

Although recorded at elevations up to5,300 feet (Zeiner et al. 1990), burrowing owlsare primarily found in low elevation valleys.On the Los Padres National Forest, these owlshistorically occurred in the Santa Ynez Moun-tains but now appear to be absent. They dostill nest in the Carrizo Plain and possibly inthe Cuyama Valley (Lehman 1994). A few bur-rowing owls may still occur along lower desertslopes and inland valleys in the other assess-ment area mountain ranges, but there are nodocumented populations in any of them.

Habitat: Burrowing owls inhabit dry,sparse grasslands, desert scrub, and agriculturalareas. Rodent burrows, usually those of Cali-fornia ground squirrels, are utilized for roostingand nesting (Unitt 1984; Lehman 1994).

Conservation Considerations: Burrowingowls have been adversely affected by loss oflowland habitats and by the widespread use ofpesticides to control ground squirrel popula-tions. Given its distribution and habitatrequirements, the burrowing owl is a specieswhose conservation cannot be significantlyinfluenced by management of national forestsystem lands within the assessment area.

Swainson’s hawk (Buteo swainsoni)Status and Distribution: The Swainson’s

hawk is a Forest Service Region 5 SensitiveSpecies and is listed as threatened by the stateof California. Historically (i.e., prior to the1930s), this species commonly nested in thecoastal lowlands of southern California inplaces like Santa Monica, Temecula, Corona,and Santee (Garrett and Dunn 1981; Unitt1984). However, breeding populations in thecoastal valleys have long been extirpated andSwainson’s hawks are not likely to recolonizethe area (SDNHM 1998).

The only localities close to the assessmentarea where Swainson’s hawks may still nest are

in the Antelope Valley north of the CastaicRanges and in eastern San Luis ObispoCounty (Garrett and Dunn 1981).

Habitat: During the breeding season,Swainson’s hawks are closely associated withopen grassland or agricultural lands (particu-larly alfalfa fields) that contain scattered treeswhich can be used for nesting. Migrants maybe noted over any habitat, but spring concen-trations are usually found over desertgrasslands (Garrett and Dunn 1981).

Conservation Considerations: Given theknown distribution and habitat requirementsof Swainson’s hawks, their conservation is notlikely to be significantly influenced by man-agement of national forest system lands withinthe assessment area.

Loggerhead shrike (Lanius ludovicianus)Status and Distribution: The loggerhead

shrike is a California Species of Special Con-cern. It is widely distributed at low elevations(below approximately 5,000 feet) across theassessment area but is limited by the availabil-ity of suitable open habitat. It has been foundnesting at Garner Valley in the San JacintoMountains (D. Freeman, unpub. notes). Arid,open country on the eastern side of the south-ern Santa Lucia Range and southern LosPadres ranges are probably the largest areas ofsuitable habitat for this species.

Habitat: Loggerhead shrikes are typicallyfound in dry, open habitats with sparse shrubsand trees (Zeiner et al. 1990b). They com-monly utilize posts, fences, and utility lines asperches.

Conservation Considerations: Suitableshrike habitat occurs on public lands in theassessment area but is not extensive. The habi-tat requirements of this species generallyindicate low vulnerability to existing land useactivities on public lands.

Animals of Coastal Scrub andChaparral Habitats

Thirteen of the animal species that re-ceived individual consideration are associatedwith scrub or chaparral habitats (table 4.13).

172

Inhabitants of Coastal Sage Scrub andOther Habitats Below 3,000 Feet

Five of the species that received individualconsideration are associated with coastal sage

This group is further subdivided into the fol-lowing categories: (1) species restricted tocoastal sage scrub and other habitats foundonly at elevations below 3,000 feet; (2) inhab-itants of both coastal scrub and chaparralhabitats, but only on the coastal (cismontane)side of the mountains; and (3) inhabitants of

Table 4.13. Animals associated with coastal scrub or chaparral habitats that received individualconsideration. Displayed for each species: (1) the level of knowledge about where it occurs in southern Californiaand, in parentheses, the estimated percentage of locations that are on national forest system lands; (2) themountain subareas occupied (y = occurs in breeding season, h = historically occurred, p = potentially occurs,t = transient, w = winter visitor)—if the species is localized and data are available, the approximate number ofoccurrences may be displayed; (3) the vulnerability of populations on national forest system lands to existing threatfactors; (4) population trends; and (5) the assigned conservation category.

Scrub and ChaparralAnimals of Concern

federal status

(1)Knowledgeof SoCalLocations

(% on NFs)

(5)Conser-vation

Category

(4) Pop.Trend

(3)Vulner-ability

on NFs

(2) areas occupied or estimated # of occurrences if spp. localized

San Bern. NFCleveland NF Angeles NF Los Padres NFSan

DiegoRngs

SanJacMts

SntaAnaMts

SanBernMts

No.SL

Rng

So.SL

Rng

SanGabMts

Cas-taic

Rngs

So.LP

Rngs

Primarily Coastal Sage Scrub or <3,000 ft

Quino checkerspot Mod h/p p p p p Mod Decl1 Site endangered (< 5%) specific

Orange-throated whiptail Mod y y y Low Unkn Landscape(< 2%) level

California gnatcatcher High 30-50 10-20 p p p High Decl2 Site threatened (< 2%) pairs pairs specific

Coastal cactus wren High y y p p y p Mod Unkn Landscape(< 1%) level

Rufous-crowned sparrow Mod-High y y y y y y y Mod Unkn Landscape(< 10%) level

Primarily Cismontane Chaparral & ScrubHermes copper butterfly Mod y Low Unkn Landscape

(10-40%) level

Coast patch-nosed Low y y y y y y y p Low Unkn Landscape snake (30-50%) level

Bell’s sage sparrow Mod y y y y y y y y y Mod Unkn Landscape(30-60%) level

In Both Cismontane & Desert Scrub/Chap.

Pratt’s blue butterfly Low 2-4 Unkn Unkn Landscape(?) pops. level

Coast horned lizard High y y y y y y y y y Mod Decl3 Landscape(> 50%) level

Coastal rosy boa Mod-Low y y y y y Mod Decl3 Landscape(10-40%) level

Red diamond rattlesnake Mod y y y Low Unkn Landscape(30-50%) level

San Diego pocket mouse Mod y p y y y Low Unkn Landscape(20-60%) level

1 U.S. Fish and Wildlife Service (1997d)2 U.S. Fish and Wildlife Service (1993b)3 Jennings and Hayes (1994)

shrublands on both coastal and desert sides ofthe mountains.

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Habitat: The primary larval food plant forquino checkerspot is Plantago erecta, but it alsoutilizes other Plantago species as well asCastilleja exserta and Keckiella antirrinoides(Mattoni et al. 1997). The primary food plant,and thus the butterfly, is not strongly associ-ated with a single plant community; rather, itis found in sparsely vegetated openings em-bedded in a variety of vegetation types butmost commonly within coastal sage scrub,chaparral, or oak woodlands.

Where Plantago erecta is present, optimumstand structure for quino reportedly consistsof patchy shrub or small tree landscapes withopenings of several meters between large plants(Mattoni et al. 1997). The butterfly typicallydoes not occur in extensive open grasslands,even where Plantago erecta is abundant, al-though apparently there are exceptions (e.g.,in the Murrieta area).

There are indications that the distributionof Plantago erecta and other native annuals mayoften be associated with the presence ofcryptobiotic crusts on the soil surface (Mattoniet al. 1997). These crusts appear to inhibitinvasions of non-native grasses and forbs, pro-viding a competitive advantage for the nativeannuals. Other edaphic factors (e.g., high clay

scrub or other predominately shrubland habi-tats that occur below 3,000 feet elevation onthe coastal side of the mountains. These habi-tats are not well represented in the assessmentarea.

Quino checkerspot butterfly(Euphydryas editha quino)

Status and Distribution: The quinocheckerspot butterfly was federally listed as en-dangered in 1997. Once considered abundantin Orange, San Diego, and western Riversidecounties, it has declined dramatically, dueprobably to the combined effects of habitatloss and population fragmentation (Murphy1990; USFWS 1997d). The quino’s historicrange along the southern California coast andinland valleys includes northernmost occur-rences in Los Angeles and San Bernardinocounties and southernmost localities in theSierra Juarez of Baja California, Mexico(Mattoni et al. 1997). Currently, it is docu-mented only from several areas insouthwestern Riverside County, southern SanDiego County, and Baja (Mattoni et al. 1997).

Nearly all of the historic and current loca-tions of this butterfly are outside theassessment area, in more coastal areas of SanDiego and Orange counties and in the lowelevation valleys of western Riverside County(fig. 4.19). However, there is a 1975 museumspecimen from “Mount Palomar” and someof the remaining populations in RiversideCounty are near the north slope of Palomar(i.e., near Vail Lake and Aguanga) (Mattoniet al. 1997; Hawks, Ballmer, and Pratt,unpubl. notes 1997). The Oak Mountaincolony near Vail Lake is considered to be a“source population”; thus, potential habitatalong the north side of Palomar Mountain hasan increased likelihood of being occupied.There is a confirmed sighting at Oak Grovejust outside the Cleveland National Forestboundary and an unconfirmed sighting nearDripping Springs campground, which is onnational forest system lands (G. Ballmer, pers.comm.).

Extant occurrences on the slopes of OtayMountain, Tecate Peak, and several other lo-

cations in southern San Diego County sug-gest there may be remaining populations onthe southern end of the Cleveland NationalForest. Potential habitat exists in that area onthe slopes of Lawson and Lyons peaks andPoser and Viejas mountains. Seemingly suit-able habitat also remains on the west side ofthe Santa Ana Mountains (e.g., Black StarCanyon), but the fact that quino has not beenlocated in Orange County since the 1960s(Mattoni et al. 1997) lowers the likelihood ofpopulations in that area. There may be higherpotential on the east side of the range (e.g.,Elsinore Peak), which is relatively close to ex-tant populations in the Murrieta area. Suitablehabitat within the historic range of the quinomay also be present along the base of the SanGabriel, San Bernardino, and San Jacintomountains, but there are no known popula-tions near those areas.

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Figure 4.19. Current and historic locations of the quino checkerspot butterfly in relation to the assessmentarea and national forest system lands (this map may not show all known localities).

content) may similarly inhibit non-natives andmight serve as indicators of potential habitat.

Topographic relief such as raised mounds,hills, slopes, or ridges may be an importanthabitat component (Mattoni et al. 1997). Thephenomenon of hilltopping, where butterfliescongregate on ridges or hilltops to mate, hasbeen observed at a number of quino locations.All of the known extant quino populations areat elevations below 3,500 feet.

Conservation Considerations: Surveys areneeded to determine the distribution of quinocheckerspot butterflies on public lands withinthe assessment area. Particular emphasisshould be given to potential habitat areas on

the Cleveland National Forest that are nearextant populations.

If colonies are found, habitat managementfor quino will likely center on maintainingample populations of the larval food plants.Although Plantago erecta still occurs in manyareas, there are indications that it has becomeless abundant as non-native annual grasses andforbs have spread. Soil disturbance, particu-larly degradation of cryptobiotic crusts, cansubstantially hamper the ability of Plantagoand other native annuals to hold their own ona site (J. Byers, Riverside Fire Lab, pers.comm.). Thus ground-disturbing activities,such as intensive livestock grazing or off-road

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Chapter 4vehicle traffic, can contribute to the declineof quino food plants.

Plantago erecta and other native annualsoften become abundant in coastal scrub andchaparral for several years immediately after afire, until the canopy is closed by the regener-ating shrub layer. Thus, a shifting age-classmosaic is desirable in these shrublands tomaintain a steady supply of early successionalpatches for native annuals. However, thisshould not trigger calls for shorter fire-returnintervals, particularly in coastal scrub, sincefrequent fires in these shrublands usually in-creases the abundance of non-native annualgrasses (Zedler et al. 1983).

Orange-throated whiptail(Cnemidophorus hyperythrus beldingi)

Status and Distribution: The orange-throated whiptail is a California Species ofSpecial Concern. Its geographic range extendsfrom Orange and the southern edge of SanBernardino counties south to around Loretoin Baja California, Mexico (Jennings andHayes 1994). Its reported elevation range inCalifornia is from near sea level to about 3,400feet (Jennings and Hayes 1994), but it is mostcommonly found at elevations below 2,300feet (Fisher and Case 1997).

Orange-throated whiptails occur at lowelevations on the coastal side of the San Di-ego Ranges, the Santa Ana Mountains, andSan Jacinto Mountains. They are common onstreamside terraces along the upper San Di-ego River in the Cleveland National Forest andalso were found on Starr Ranch at the base ofthe Santa Ana Mountains (Fisher and Case1997). They likely occur in Bautista Canyonin the San Jacinto Mountains.

Habitat: The orange-throated whiptail oc-curs in coastal sage scrub and, to a lesser extent,chaparral. It appears to reach peak densitieson floodplains and streamside terraces(Jennings and Hayes 1994).

Conservation Considerations: Orange-throated whiptails occur in some of the lowestelevation areas within the southern part of theassessment area. The proximity to urbanizingareas increases the potential for whiptail popu-

lations to become fragmented and isolated.The food base of orange-throated whiptails(principally termites), may be adversely af-fected by invasions of Argentine ants fromirrigated areas (Jennings and Hayes 1994).

California gnatcatcher(Polioptila californica)

Status and Distribution: The Californiagnatcatcher was federally listed as threatenedin 1993 (USFWS 1993b). The current knowndistribution of California gnatcatchers isconcentrated along the coast in maritime-influenced areas of Orange and San Diegocounties (Mock 1998). There are also sizablepopulations in the inland valleys of southwest-ern Riverside County and on the Palos VerdesPeninsula (Atwood 1993). Within the assess-ment area, the only known Californiagnatcatcher population on national forest sys-tem lands is on the Cleveland National Forest(fig 4.20). However, recent sightings atSycamore Flat (near Lytle Creek), at theconfluence of Lytle Creek and Cajon Wash,and on the Etiwanda Fan (Davis et al. 1998)indicate a possible population along the lowerfoothills of the eastern San Gabriel Mountainsthat may extend onto the San Bernardino andAngeles national forests. There is also a slightpossibility that gnatcatchers may also occuron the lower western slopes of the San JacintoMountains.

On the Cleveland, the largest population(thirty-plus pairs) is along the upper San Di-ego River above El Capitan Reservoir. Smallclusters have also been observed in the vicin-ity of Pamo Valley near Ramona and on thelower slopes of the Santa Ana Mountains onthe east side near Lake Elsinore and on thewest side near San Juan Creek.

Habitat: California gnatcatchers arenonmigratory and strongly associated withDiegan and Riversidian coastal sage scrub(Atwood 1993). These types of sage scrub oc-cur in Los Angeles, Orange, Riverside, SanBernardino, and San Diego counties at eleva-tions below 3,000 feet on the coastal side of themountains. However, gnatcatcher densities seem

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Figure 4.20. Known locations of the California gnatcatcher within or near the assessment area (this mapdoes not show all known localities outside the assessment area).

to decline substantially at elevations aboveabout 2,200 feet and at increasing distancesfrom the coast (Mock 1998).

Total shrub cover appears to be more im-portant than shrub height in determininghabitat suitability (Beyers and Wirtz 1997).California gnatcatchers are most abundant inmature stands, where shrub canopy cover istypically greater than 50 percent and oftenexceeds 60 percent (Atwood 1993; Beyers andWirtz 1997). However, they will forage in re-cently burned sites and pairs have beenobserved establishing territories in burned ar-eas within three years postfire at coastal sites

(Wirtz et al. 1997). The rapidity of shrub re-growth appears to affect the rate at whichgnatcatchers reoccupy burned areas, and in-land sites (particularly Riversidian sage scrub)are slower to recover than coastal sites (Wirtzet al. 1997).

Conservation Considerations: Althoughthe potential for major new populations is low,surveys are needed to more fully determinethe distribution of California gnatcatchers inthe Cleveland, San Bernardino, and Angelesnational forests. Information on occurrencesat low elevations in the eastern San GabrielMountains would be particularly useful.

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Chapter 4Conservation of coastal sage scrub where itdoes occur within the assessment area is im-portant for the gnatcatcher.

The gnatcatcher population on the upperSan Diego River has been negatively affectedby recurring fires in the early 1990s. High firefrequencies and invasions of exotic grasses areserious problems in gnatcatcher habitat(Minnich and Dezzani 1998). Coastal sagescrub is a highly flammable vegetation typeand maintaining mature stands in fire-proneareas near the urban interface is a significantmanagement challenge (Beyers and Wirtz1997). Cowbird nest parasitism is also a prob-lem for gnatcatchers in some areas Braden etal. 1997) and has been documented in the up-per San Diego River population.

Coastal cactus wren(Campylorhynchus brunneicapillus ssp.)

Status and Distribution: The San Diegocoastal cactus wren (C. b. sandiegoense) is aForest Service Region 5 Sensitive Species anda California Species of Special Concern. Reaand Weaver (1990) define the range of thissubspecies as coastal portions (i.e., west of themountain crest) of San Diego and southernOrange counties (Trabuco Canyon is thenorthern boundary). There are no known lo-cations of coastal cactus wrens within theCleveland National Forest, although they havebeen observed close by. On the coastal slopesof the Santa Ana Mountains, they have beenobserved at Starr Ranch, Live Oak CanyonPark, and Caspers Wilderness Regional Park.In San Diego County, they have been foundabove El Capitan Reservoir on the San DiegoRiver and in Pamo Valley.

Coastal-slope populations of cactus wrensin Riverside, San Bernardino, Los Angeles,Ventura, and northern Orange counties areclassified as C. b. anthonyi, which is the samesubspecies that occurs in the deserts of Cali-fornia and western Arizona (Rea and Weaver1990). Given its abundance in the desert, thissubspecies is not considered to be rare or sen-sitive. However, coastal-slope populations ofcactus wrens are rare and we regard them as a

local viability concern. Cactus wrens are scat-tered across the lower slopes of the San GabrielMountains (e.g., Fish Canyon, Duarte, andClaremont) (D. Cooper, UC Riverside, pers.comm.) and may also extend into the foot-hills of the San Bernardino and San Jacintomountains.

Habitat: Coastal cactus wrens are closelyassociated with coastal sage scrub vegetationthat contains patches of cholla or prickly pear(Opuntia spp.) cactus (Rea and Weaver 1990).The wren’s chief requisite is tall Opuntia cacti.The wrens construct their nests in these cactiand supplement their insect diet in fall andwinter by feeding on cactus fruit (Rea andWeaver 1990).

Conservation Considerations: Althoughthe potential for major populations is low, sur-veys are needed to more fully determine thedistribution of cactus wrens in the low coastalfoothills that lie within the Cleveland, SanBernardino, and Angeles national forests.

Rufous-crowned sparrow(Aimophila ruficeps canescens)

Status and Distribution: The southernCalifornia rufous-crowned sparrow, A. r.canescens, is a California Species of SpecialConcern. It occurs from Santa Barbara Countysouth to northwestern Baja California at lowelevations on the coastal side of the moun-tains (Garrett and Dunn 1981; Unitt 1984).This sparrow is occasionally found on thedesert side of the mountains, particularly onthe northern end of the San Jacinto Moun-tains (e.g., near Cabazon) and in southern SanDiego County. It is described as being ratherscarce on the lower coastal slopes of the SanBernardino Mountains (Garrett and Dunn1981).

Habitat: Preferred habitat for this spar-row consists of slopes, typically south facing,with sparse brush intermixed with bunchgrasses and large rocks. These slopes are oftenquite steep and rocky (Garrett and Dunn1981; Unitt 1984). The range of this subspe-cies is virtually coincident with extensivestands of coastal sage scrub, although it does

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appear to be more adaptable than the Cali-fornia gnatcatcher and cactus wren in that itextends further up into the foothill scrub-chaparral transition zone (Unitt 1984).Rufous-crowned sparrows do not occupydense chaparral but can be found in recentlyburned chaparral or along firebreaks as longas other key habitat elements (e.g., grasses androcks) are present.

Conservation Considerations: Coastalsage scrub is a declining habitat type and onethat is poorly represented on public lands inthe assessment area. Conservation of this typewhere it does occur is important for therufous-crowned sparrow. Additional informa-tion is needed on the distribution andabundance of this species in the foothill scrub-chaparral transition zone, since that type ofhabitat is much more extensive on publiclands. Surveys associated with the develop-ment of breeding bird atlases in Los Angeles(LACBBA 1999) and San Diego (SDNHM1999) counties should help in this regard.

Inhabitants of Coastal-side Chaparraland Scrub

Three of the species that received indi-vidual consideration can occur in eitherchaparral or scrub habitats. The ability of thesespecies to occur in higher elevation chaparralhabitats increases the potential to conservethem on public lands within the assessmentarea.

Hermes copper butterfly (Lycaena hermes)Status and Distribution: The Hermes

copper is a former federal C2 Candidate Spe-cies and now is on the federal special concernlist. It is known only from western San DiegoCounty and a small portion of adjacent north-western Baja California, Mexico (Brown1991). Initial collections of this species wereall in the immediate vicinity of San Diego,but it has proven to be more widespread thanoriginally thought, particularly across thebroad chaparral belt east of San Diego. TheHermes copper is known to extend inland to

Viejas Grade, Guatay, and Pine Valley(Murphy 1990; Brown 1991). Thus, a signifi-cant amount of its known range is within theCleveland National Forest.

Habitat: The Hermes copper is restrictedto mixed chaparral and coastal sage scrub com-munities where its larval host plant, redberry(Rhamnus crocea), occurs (Brown 1991). Colo-nies are confined closely to the vicinity of thehost plant, with adults frequently observednectaring on flat-topped buckwheat(Eriogonum fasciculatum) (Thorne 1963).

Conservation Considerations: Redberry,the larval host plant, is a common componentof chaparral and coastal scrub and is not be-lieved to be vulnerable to existing land uses orfire regimes.

Coast patch-nosed snake(Salvadora hexalepis virgultea)

Status and Distribution: The coast patch-nosed snake is a California Species of SpecialConcern. Its range extends from near Crestonin San Luis Obispo County southward pri-marily on the coastal side of the mountainsinto Baja California (Jennings and Hayes1994). Its known elevation range is from nearsea level to around 7,000 feet (Jennings andHayes 1994), but it is typically found below5,000 feet (Glaser 1970). The species appearsto be widespread on national forest systemlands, but not in high densities.

Habitat: Patch-nosed snakes seem to pre-fer coastal sage scrub and chaparral (Fisher andCase 1997). Their primary prey is whiptail liz-ards and this may be what determines thehabitat preferences of this snake (Jennings andHayes 1994).

Conservation Considerations: The abun-dance of coast patch-nosed snakes on publiclands in the assessment area is not known.However, this species does not seem particu-larly vulnerable to existing change agents onpublic lands. Based on what we currently knowof its distribution and life history characteris-tics, we believe it can be conserved throughlandscape-scale, habitat-based management. Itwould be a difficult species to monitor fortrends in abundance.

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Chapter 4Bell’s sage sparrow (Amphispiza belli belli)

Status and Distribution: The Bell’s sagesparrow is a California Species of Special Con-cern. Sage sparrows occur on both coastal anddesert slopes, but the subspecies A. b. belli oc-curs only on the coastal side. Its geographicrange extends from northern California intoBaja California. This subspecies extends intolower montane chaparral habitats, which in-creases its representation in the assessmentarea. Portions of western Riverside and SanDiego counties are identified as centers ofabundance for this sparrow (Garrett and Dunn1981).

Habitat: The Bell’s sage sparrow is associ-ated with dry chaparral in interior foothills; italso occurs in coastal sage scrub (Garrett andDunn 1981). This sparrow is said to inhabitdense stands (Garrett and Dunn 1981; Unitt1984), but a recent account suggests it is mostcommon in semi-open chaparral and describesareas of bare ground unencumbered by heavyleaf litter as essential (SDNHM 1998). Thelatter description is consistent with recentdata from the Cleveland National Forest,where sage sparrows were found to be sig-nificantly more abundant in open,young-age (recently burned) chaparral thanthey were in denser, older stands (Boyd andStephenson 1997).

Conservation Considerations: This spe-cies appears to be well represented on publiclands in coastal foothill and lower montaneareas. One recent study suggests that a chap-arral age-class mosaic interspersed with open,young stands is important to this sparrow(Boyd and Stephenson 1997).

Inhabitants of Coastal and Desert-sideShrublands

Five of the species that received individualconsideration can occur in chaparral and scrubhabitats on both coastal and desert sides ofthe mountains. In general, this wider geo-graphic range increases the potential for thesespecies to occur on public lands within theassessment area.

Pratt’s blue butterfly(Euphilotes enoptes cryptorufes)

Status and Distribution: This is a recentlydescribed subspecies (Pratt and Emmel 1998)and is not on any special concern lists. It isconsidered here because much of its knownrange is within the assessment area. Knownlocations of this butterfly include the south-facing slope of Pyramid Peak in the southernpart of the San Jacinto Mountains and on theroad to Santa Rosa Mountain at elevations of4,500 to 5,000 feet (Pratt and Emmel 1998).The range of this subspecies also extends intonorthern Baja California in the San PedroMartir Mountains.

Habitat: The Pratt’s blue is associated withthe wild buckwheat species, Eriogonumdavidsonii. Specifically it has only been foundon the spring blooming, and not the summerblooming, variety of this buckwheat, whichoccurs predominantly on south-facing slopes(Pratt and Emmel 1998).

Conservation Considerations: More in-formation is needed on the distribution andabundance of this species. There are no im-minent threats to the two localities where thisbutterfly has been observed.

Coast horned lizard(Phrynosoma coronatum)

Status and Distribution: Two differentsubspecies of coast horned lizard occur in theassessment area. P. c. blainvillii, the San Di-ego horned lizard, is a Forest Service Region 5Sensitive Species and a California Species ofSpecial Concern. P. c. frontale, the Californiahorned lizard, is a California Species of Spe-cial Concern. The two subspecies combinedinhabit all of the mountain subareas in theassessment area.

The geographic range of P. c. blainvilliistretches from Ventura County south into BajaCalifornia, Mexico. The distribution map forthis subspecies in Jennings and Hayes (1994)suggests its northwestern-most occurrence isin the upper Cuyama River watershed. It oc-curs on all four national forests and reachesalmost 7,000 feet elevation in places (e.g.,

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Habitat: The red diamond rattlesnaketypically occurs in brushy habitats that con-tain large rocks or boulders (Klauber 1972).It is frequently observed in chamise and red

Tahquitz Meadow on Mount San Jacinto)(Jennings and Hayes 1994). Although mostcommon on the coastal slope, San Diegohorned lizards also occur on the desert side ofthe mountains.

P. c. frontale overlaps with P. c. blainvilliiin northern Los Angeles and Ventura coun-ties and there is evidence of hybridization insome areas (Jennings and Hayes 1994). Therange of P. c. frontale continues north intoShasta County. It occurs on both the coastalside and the San Joaquin Valley side of themountains.

Habitat: Horned lizards can be found ina variety of habitats but are most common inshrub-dominated communities. Key habitatelements are loose, fine soils with a high sandfraction; an abundance of native ants; openareas with limited overstory for basking; andareas with low, dense shrubs for refuge(Jennings and Hayes 1994). Fisher and Case(1997) found coast horned lizards primarilyin association with either cryptogamic soils orsandy soils. The coast horned lizard’s primaryfood is harvester ants (Pogonomyrmex spp.);the lizards do not appear to eat Argentineants.

Conservation Considerations: Coasthorned lizards are reported to be declining,primarily due to loss of habitat in low eleva-tion coastal and inland valleys (Jennings andHayes 1994). Thus, public lands within theassessment area are becoming increasingly im-portant to the conservation of this species.

The most significant threat to horned liz-ards on public lands may be progressiveelimination of its food base by exotic ants,particularly in areas near human developments(Jennings and Hayes 1994; Suarez et al. 1998).The elimination of native ant colonies fromsmall habitat fragments by Argentine ants hasalready been documented in southern Cali-fornia (see chapter 3). The recent arrival ofred imported fire ants could make this prob-lem worse.

Coastal rosy boa(Lichanura trivirgata roseofusca)

Status and Distribution: The coastal rosyboa is a Forest Service Region 5 Sensitive Spe-cies. It occurs from the foothills of the SanGabriel and San Bernardino mountains, souththrough Orange, Riverside and San Diegocounties, down to the Sierra San Pedro Martirin Baja California (Klauber 1931; Gorman1965). There reportedly is a record of this spe-cies at an elevation of 8,000 feet in the SanGabriel Mountains (Fisher and Case 1997), butit typically is found much lower. It occurs onboth coastal and desert sides of the mountains.

Habitat: The coastal rosy boa is primarilyassociated with rocky habitat in scrub andchaparral, and in the mountains is often foundin canyons and washes (Klauber 1931; Fisherand Case 1997).

Conservation Considerations: The rosyboa is an attractive, docile snake that has con-siderable market value in the pet trade. Illegalcollection of wild snakes is believed to be asignificant problem in some areas (Hollandand Goodman 1998; J. Copp, CA Academyof Sciences, pers. comm.).

Red diamond rattlesnake(Crotalus ruber ruber )

Status and Distribution: The red dia-mond rattlesnake is a California Species ofSpecial Concern. It occurs on both coastal anddesert slopes of the San Jacinto, Santa Rosa,and Santa Ana mountains, and the mountainsof San Diego County (fig. 4.21). Its knownelevation range is from near sea level to about5,000 feet (Jennings and Hayes 1994), al-though it is typically found below 4,000 feet(Klauber 1972). Sighting records indicate thisspecies is well represented on the ClevelandNational Forest and the San Jacinto Districtof the San Bernardino National Forest (Glaser1970).

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Figure 4.21. The approximate range of the red diamond rattlesnake.

shank chaparral as well as coastal sage scruband desert scrub (Jennings and Hayes 1994).

Conservation Considerations: Urban de-velopment and irrigated agriculture,particularly avocado orchards, have signifi-cantly reduced the amount of suitable habitatfor this species (Jennings and Hayes 1994).However, the red diamond rattlesnake doesnot seem particularly vulnerable to existingchange agents on public lands. Its distribu-tion and life history characteristics suggest itcan be conserved through landscape-scale,habitat-based management. It would be a dif-ficult species to monitor for trends inabundance.

San Diego pocket mouse(Chaetodipus fallax)

Status and Distribution: The San Diegopocket mouse is a California Species of Spe-cial Concern. The northern limits of thisspecies’ range extend from the eastern SanGabriel Mountains in the interior to near SanOnofre along the coast (Lackey 1996). It oc-curs south of that line well into Baja California.Two different subspecies occur in the assess-ment area. C. f. fallax occurs on the coastalside of the mountains and the lighter coloredC. f. pallidus is found on the desert side (Lackey1996).

Suitable habitat for this mouse appears toextend well up into the mountains on desert-side

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Monterey salamander(Ensatina eschscholtzii eschscholtzii)

Status and Distribution: The Montereysalamander is a local species of concern be-cause it is relatively uncommon and much ofits distribution is at low elevations on privatelands. It occurs in the valleys, foothills, andlower montane slopes of every mountain rangein the assessment area. No population trendinformation is reported for this species.

Three subspecies of Ensatina eschscholtzii(the other two are considered in the mixedhardwood-conifer forest group) occur in themountains of southern California, and theirevolutionary relationships and taxonomic sta-tus have received considerable scientificattention (Stebbins 1949; Brown 1974; Wakeand Yanev 1986; Wake et al. 1986; Highton1998; Wake and Schneider 1998). E. e.eschscholtzii is the most distinct of the threesubspecies; it is a reddish-brown, unblotchedsalamander that is believed to have evolvedfrom low-elevation coastal regions to thenorth. The other two subspecies are darkerwith prominent yellow or orange blotches.They are believed to have originated in thenorthern interior mountains and moved souththrough the Sierra Nevada and Tehachapimountains (Wake and Yanev 1986).

Habitat: Monterey salamanders are mostcommon in oak woodlands with extensive leaflitter and downed wood (Holland andGoodman 1998). However, they do occupy awide variety of other habitats and extend toelevations above 6,100 feet in some areas (e.g.,Sawmill Canyon north of Banning in the SanBernardino Mountains) (Wake et al. 1986).They are rarely seen on the ground surfaceexcept during and immediately after rains.

Conservation Considerations: These sala-manders are impacted by habitat loss due todevelopment on private lands but are not con-sidered to be particularly vulnerable toprevailing land use activities on public lands.Over-collection of standing trees and downedlogs in oak woodlands can be a problem nearroads and undoubtedly reduces habitat qual-ity for this species.

slopes. The species has been found at 4,500feet in the Santa Rosa Mountains and at 6,000feet at Cactus Flat on the north side of theSan Bernardino Mountains (Zeiner et al.1990b).

Habitat: On the coastal side of the moun-tains, San Diego pocket mice are foundprimarily in coastal sage scrub (Vaughan 1954;Lackey 1996), reaching peak abundance inrocky areas within that habitat (Price andWaser 1984). Vaughan (1954) reported thatthis mouse does not extend into even the loweredge of the chaparral belt on the coastal slopesof the San Gabriel Mountains.

A broader range of habitats appears to beoccupied on the desert side of the mountains.It has been found in pinyon-juniper wood-land, desert scrub, rocky slopes, andagave-ocotillo habitat (Lackey 1996). Ondesert slopes of the eastern San Gabriel Moun-tains, the San Diego pocket mouse’sdistribution was closely correlated with thepresence of yucca, particularly on dry, rockysouthern slopes (Vaughan 1954).

Conservation Considerations: The SanDiego pocket mouse appears to be well repre-sented on public lands on the desert side ofthe mountains. It does not seem particularlyvulnerable to land use activities in those ar-eas. However, if its coastal-side distribution isstrictly limited to coastal sage scrub, it may bequite rare on that side of the assessment area.More information is needed on the distribu-tion and abundance of this species in potentialhabitat on the coastal side of the assessmentarea.

Animals of Foothill OakWoodland and Savanna Habitats

Five of the animal species that receivedindividual consideration are associated withfoothill woodland and savanna habitats (table4.14). Although relatively few rare animal spe-cies are restricted to foothill oak woodlands,it should be recognized that species diversityand richness are very high in these habitats,since they provide high quality habitat formany species.

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Arboreal salamander (Aneides lugubris)Status and Distribution: The arboreal

salamander is a local species of concern be-cause it is relatively uncommon and much ofits distribution is at low elevations on privatelands. It reportedly occurs in the foothills andlower elevations of every mountain range inthe assessment area (Stebbins 1951), althoughit is seldom seen. No population trend infor-mation is reported for this species.

Habitat: Arboreal salamanders are typi-cally found in oak woodlands, particularlywhere coast live oak is a major component(Stebbins 1951; Holland and Goodman1998). However, in southern California it hasbeen observed in other habitats, including sy-camore-dominated riparian (R. Fisher, USGSBiological Resources Division, pers. comm.)and chaparral (T. Scott, UC Riverside, pers.comm.). Leaf litter and downed logs are be-lieved to be important habitat elements forthis species.

Conservation Considerations: Same asthose described for the Monterey salamander.

Yellow-billed magpie (Pica nuttalli)Status and Distribution: The yellow-

billed magpie is a local species of concernbecause it has a small geographic range (Sac-ramento and central coast valleys) and muchof its distribution is at low elevations on pri-vate lands. Magpies occur from the upperSalinas Valley south to the Santa Ynez Valley,and east to the inland limit of oak savanna(fig. 4.22) (Garrett and Dunn 1981). Theyformerly occurred south to Conejo Valley onthe Ventura/Los Angeles county line (Willet1933) but apparently were absent from thereby the 1930s (Garrett and Dunn 1981).

1 Based on BBS data for California (Sauer et al. 1997)

Table 4.14. Animals associated with foothill oak woodland and savanna habitats that receivedindividual consideration. Displayed for each species: (1) the level of knowledge about where it occurs insouthern California and, in parentheses, the estimated percentage of locations that are on national forest systemlands; (2) the mountain subareas occupied (y = occurs in breeding season, h = historically occurred, p = potentiallyoccurs, t = transient, w = winter visitor)—if the species is localized and data are available, the approximate numberof occurrences may be displayed; (3) the vulnerability of populations on national forest system lands to existingthreat factors; (4) population trends; and (5) the assigned conservation category.

GeneralistMonterey salamander Moderate y y y y y y y y y Low Unkn Landscape

(25-50%) level

Oak SavannaYellow-billed magpie High y y y Low Stable1 Landscape

(10-25%) level

Mature Live Oak GrovesArboreal salamander Mod-Low y y y y y y y y y Low Unkn Landscape

(25-50%) level

Western screech owl High y y y y y y y y y Mod Unkn Landscape(30-60%) level

Long-eared owl Mod-Low y y y y y y y y y Mod Unkn Landscape(< 25%) level

Foothill Oak Woodland& Savanna Animals

federal status

(1)Knowledgeof SoCalLocations

(% on NFs)

(5)Conser-vation

Category

(4) Pop.Trend

(3)Vulner-ability

on NFs

(2) areas occupied or estimated # of occurrences if spp. localized

San Bern. NFCleveland NF Angeles NF Los Padres NFSan

DiegoRngs

SanJacMts

SntaAnaMts

SanBernMts

No.SL

Rng

So.SL

Rng

SanGabMts

Cas-taic

Rngs

So.LP

Rngs

Although localized in distribution, mag-pies are often common where they occur.Breeding bird survey data from 1966 to 1996for the California foothills and the entire state

184

Figure 4.22. The approximate range of the yellow-billed magpie.

both show a very stable trend in the abundanceof yellow-billed magpies (Sauer et al. 1997).

Habitat: Yellow-billed magpies occupyoak savanna, open oak-riparian woodland, andpastureland (Lehman 1994).

Conservation Considerations: Magpiesare probably not particularly vulnerable to pre-vailing land use activities on public lands.However, only small portions of the yellow-billed magpie’s occupied range lie on publicland. The ability of this species to persist inincreasingly developed areas is uncertain.Magpies do very well in ranchland situationsand probably are okay in more developedranchette environments, but it is unclear howthey fare in suburban areas.

Western screech owl (Otus kennicottii)Status and Distribution: The western

screech owl is a local species of concern be-cause it is relatively uncommon and much ofits distribution is at low elevations on privatelands. It occurs in the valleys, foothills, andlower montane slopes of every mountain rangein the assessment area. No population trendinformation is reported for this species.

Habitat: The screech owl is most commonin mature live-oak and oak-riparian woodlandsin coastal and foothill areas but also occurs inoak-conifer forests on lower montane slopesup to at least 5,000 feet (Garrett and Dunn1981; Unitt 1984).

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Chapter 4Conservation Considerations: Screech

owls nest in mature woodlands and, thus, aredependent on old stands that cannot easily bereplaced. Mature oak woodland habitats aredeclining due to development on private lands,and stands on public lands are vulnerable toloss in stand-replacing fires.

Long-eared owl (Asio otus)Status and Distribution: The long-eared

owl is a California Species of Special Concern.Its geographic range extends across the assess-ment area, but recent observations in theregion are rare. There are a few historicalrecords of long-eared owls nesting at high el-evations (above 7,000 feet) in the SanBernardino and San Jacinto mountains, butwe found no recent observations in those ar-eas. There are recent records from CrowderCanyon and Cajon Wash in the San Bernar-dino National Forest (D. Freeman, unpubl.notes), but those areas are below 5,000 feet. Apair of long-eared owls with young were ob-served at 7,500 feet on Mount Pinos in 1981(Lentz 1993).

Bloom (1994) documented a number ofactive long-eared owl nest sites along the baseof the Santa Ana Mountains in OrangeCounty and within Camp Pendleton in north-western San Diego County. He also reviewedhistoric nesting records elsewhere in San Di-ego County. The vast majority of theselocations are west of the assessment area inthe coastal valleys and low foothills.

In a map of long-eared owl distributionin California, Zeiner et al. (1990) indicatepotential breeding areas on the desert side ofthe Castaic Ranges, in the upper Cuyama Val-ley region, and along the immediate coast inSan Luis Obispo and southern Montereycounties.

Habitat: In coastal areas of southern Cali-fornia, long-eared owls typically nest in dense,closed-canopy stands of coast live oak or ri-parian woodland that are in close proximityto open habitats such as grassland, meadow,or desert scrub (Bloom 1994). The need foradjacent grassland foraging habitat may ex-plain why this owl is not more common in

upper foothill and lower montane areas. Inthese areas, closed canopy woodlands are of-ten surrounded by dense chaparral.

In desert-side areas, long-eared owls nestin wooded riparian habitats. They regularlynest in tamarisk groves in the Anza-BorregoDesert (SDNHM 1998) and in riparian wood-land in Big Morongo Canyon, both insituations where there is a lot of adjacent openhabitat.

Conservation Considerations: More in-formation is needed on the distribution of thisspecies on public lands within the assessmentarea, particularly in the foothills where long-eared owls are now rare and vulnerable tohabitat loss on private lands. Efforts are neededto protect grassland and meadow habitats inthe vicinity of long-eared owl nest sites.

Animals of Mixed Hardwood-Conifer Forest Habitats

Ten of the animal species that received in-dividual consideration are associated withforest types that typically contain a mix ofhardwoods (e.g., oaks) and conifers (e.g., pinesand firs) (table 4.15). Many of these speciesare found in lower montane forest types suchas bigcone Douglas-fir/canyon live oak andCoulter pine/canyon live oak stands. Some ofthe species in this group, like the spotted owl,also can occur in forests that contain only co-nifers or hardwoods.

San Gabriel Mountains elfin butterfly(Incisalia mossii hidakupa)

Status and Distribution: This is a recentlydescribed taxon (Emmel et al. 1998) that isrecognized as a Species of Concern by the U.S.Fish and Wildlife Service. The San GabrielMountains elfin is known from only six loca-tions in the San Gabriel and San Bernardinomountains (Murphy 1990). Reported loca-tions from the San Gabriel Mountains are inthe San Antonio Canyon watershed (i.e.,Stoddard Canyon and 5 miles west of MountBaldy) and the Big Tujunga watershed (i.e.,near Hidden Springs) (Murphy 1990). Theonly reported locality in the San Bernardino

186

Table 4.15. Animals associated with mixed hardwood-conifer forest habitats that received individualconsideration. Displayed for each species: (1) the level of knowledge about where it occurs in southern Californiaand, in parentheses, the estimated percentage of locations that are on national forest system lands; (2) themountain subareas occupied (y = occurs in breeding season, h = historically occurred, p = potentially occurs,t = transient, w = winter visitor)—if the species is localized and data are available, the approximate number ofoccurrences may be displayed; (3) the vulnerability of populations on national forest system lands to existing threatfactors; (4) population trends; and (5) the assigned conservation category.

Invertebrates (butterflies)San Gabriel Mtns. elfin Low y y Unkn Unkn Site

(> 80%) specific

Thorne’s hairstreak Low p Mod Unkn Site(0%) specific

AmphibiansLarge-blotched High y y y1 Low Unkn Landscape salamander (30-60%) level

Yellow-blotched Mod y1 p y Low Unkn Landscape salamander (30-60%) level

San Gabriel Mtn. Mod p y Low Unkn Landscape slender salamander (> 80%) level

Tehachapi slender Low p p Unkn Unkn Minimal salamander (0%) influence

BirdsCalifornia spotted owl High ~35 3 ~20 ~120 ~60 12 ~65 ~12 ~40 Mod Decl2 Site

(50-75%) specific

Northern pygmy owl Low y p y y y y y y y Low Unkn Landscape(25-50%) level

Purple martin Mod y h y y y y y t y High Decl3 Site(25-50%) specific

Cassin’s solitary vireo High y y y y y y y y y Mod Unkn Landscape(< 25%) level

Hardwood/ConiferForest Animals ofConcern

federal status

(1)Knowledgeof SoCalLocations

(% on NFs)

(5)Conser-vation

Category

(4) Pop.Trend

(3)Vulner-ability

on NFs

(2) areas occupied or estimated # of occurrences if spp. localized

San Bern. NFCleveland NF Angeles NF Los Padres NFSan

DiegoRngs

SanJacMts

SntaAnaMts

SanBernMts

No.SL

Rng

So.SL

Rng

SanGabMts

Cas-taic

Rngs

So.LP

Rngs

1 Ensatina salamanders in the San Bernardino Mountains have color patterns more similar to the yellow-blotched subspecies, but aregenetically closer to the large-blotched subspecies (Wake and Schneider 1998).2 LaHaye and Gutierrez 1997. (specific to the San Bernardino Mountains)3 Garrett and Dunn 1981, Unitt 1984, Lehman 1994.

Mountains is near Angeles Oaks, in the SantaAna River watershed.

Habitat: The San Gabriel Mountains elfinbutterfly appears to be found primarily onsteep, north-facing slopes. The larval host plantis a stonecrop, Sedum spathulifolim, that is con-centrated and limited in extent (Murphy 1990;Emmel et al. 1998).

Conservation Considerations: All re-ported localities of this butterfly appear to beon national forest system lands. In Murphy’s

(1990) status review, Incisalia mossii hidakupais listed as a category A taxon, that is, a taxonin immediate need of protective measures. Twoother species identified as category A taxa inthis 1990 paper have subsequently been addedto the endangered species list (i.e., quinocheckerspot and Laguna Mountain skipper).

Ironically, the principal threat identifiedfor this species is over collecting and destruc-tion of host plants by butterfly collectors(Murphy 1990). The locations of these

187

Chapter 4populations should be identified by the For-est Service and protective measures institutedto reduce this threat. Additional surveys arealso needed to better determine the distribu-tion, abundance, and habitat requirements ofthis butterfly.

Thorne’s hairstreak (Mitoura thornei)Status and Distribution: The Thorne’s

hairstreak is a local species of concern. Murphy(1990) considered it a category B taxon, whichhe defined as one which warrants listing asendangered, but with a less pressing need thancategory A taxa. This butterfly is currentlyknown only from the vicinity of Otay Moun-tain near the Mexican border in southwesternSan Diego County (Brown 1991). Closely as-sociated with Tecate cypress on OtayMountain, the Thorne’s hairstreak has notbeen found at other localities where the cy-press tree occurs (Brown 1991).

Habitat: The larval host plant for this but-terfly is the Tecate cypress. A detaileddescription of the habitat on Otay Mountainwhere the Thorne’s hairstreak occurs is pro-vided in Brown (1983).

Conservation Considerations: It appearsthat the Thorne’s hairstreak does not occur atsites where Tecate cypress grows within theassessment area (Brown 1991), but additionalsurveys are needed to make a more conclusivedetermination. The biggest threat to this spe-cies is overly frequent fire that could drasticallyreduce the abundance of Tecate cypress (see“Tecate Cypress” section in chapter 2). A se-ries of recent fires on Otay Mountain hasnegatively impacted the cypress.

Large-blotched salamander(Ensatina eschscholtzii klauberi )

Status and Distribution: The large-blotched salamander is a Forest Service Region5 Sensitive Species and a California Species ofSpecial Concern. It occurs from the moun-tains of San Diego County (i.e., Laguna,Cuyamaca, Volcan, Palomar, and Hot Springs)north to the San Jacinto Mountains (Jenningsand Hayes 1994) primarily at elevations be-

tween 3,000 and 6,000 feet (fig. 4.23). Local-ized populations of blotched ensatinasalamanders in the San Bernardino Mountains(i.e., Crystal Creek, near Lake Arrowhead, andSawmill Canyon) appear to be geneticallycloser to E. e. klauberi, but have color patternsmore similar to E. e. croceater (Wake andSchneider 1998).

Habitat: Large-blotched salamanders oc-cur in a variety of habitats but are mostcommon in mixed stands of oaks (coast live,canyon live, or black) and conifers (pine, fir,and incense cedar). Down logs, leaf litter, andwoody debris appear to be important habitatelements (Jennings and Hayes 1994).

Conservation Considerations: These sala-manders are impacted by habitat lossesresulting from development on private landsbut are not considered to be particularly vul-nerable to prevailing land use activities onpublic lands. Over-collection of standing treesand downed logs in oak-conifer forests can bea problem near roads and likely reduces habi-tat quality for this species.

Yellow-blotched salamander(Ensatina eschscholtzii croceater)

Status and Distribution: The yellow-blotched salamander is a Forest Service Region5 Sensitive Species and a California Species ofSpecial Concern. It occurs in the TehachapiMountains and extends into the assessmentarea in the vicinity of Mount Pinos, FrazierMountain, and Alamo Mountain (Jenningsand Hayes 1994). Potential habitat close tothe known range of this subspecies exists onLiebre and Sawmill mountains in the Castaicregion. As previously mentioned, blotchedensatina slamanders found in the San Bernar-dino Mountains have color patterns similarto E. e. croceater.

The absence of blotched ensatina sala-manders in the San Gabriel Mountains haslong been an enigma, since there appears tobe an extensive amount of suitable habitatthere, and people continue to search for iso-lated, undiscovered populations (Wake andSchneider 1998).

188

Figure 4.23. Approximate range of the large-blotched salamander and known locations of the yellow-blotchedand San Gabriel Mountain salamanders.

Habitat: Yellow-blotched salamanders oc-cur in a variety of habitats but are mostcommon in mixed stands of oaks (black, blue,or canyon live) and conifers (pine or fir).Down logs, leaf litter, and woody debris ap-pear to be important habitat elements(Jennings and Hayes 1994).

Conservation Considerations: Same asthose described for the large-blotched sala-mander. Surveys are needed to determine ifthis species is present on Liebre or Sawmillmountains.

San Gabriel Mountain slender salamander(Batrachoseps gabrieli)

Status and Distribution: The San GabrielMountain slender salamander is a Forest Ser-vice Region 5 Sensitive Species. This recentlydescribed species is known from only a fewlocalities, all in the eastern San Gabriel Moun-tains (fig. 4.23): at Pine Flats near Crystal Lakeand Rockbound Canyon in the upper SanGabriel River watershed (Wake 1996), in SanAntonio Canyon, and in the south, middle,and north forks of Lytle Creek (R. Goodman,pers. comm., 1998). A Batrachoseps sala-mander found in Waterman Canyon in theSan Bernardino Mountains may also be this

189

Chapter 4species, although it has some different physi-cal characteristics (R. Goodman, pers. comm.,1998).

The known elevation range of this sala-mander is from 3,800 feet to 7,800 feet (Wake1996) and all localities are within either theAngeles or San Bernardino national forests.

Habitat: San Gabriel Mountain slendersalamanders have been found in mixed hard-wood-conifer forest habitats, usually nearwater and often associated with rocky talusslopes (Wake 1996). They typically occur un-der large rocks, rotting logs, downed treelimbs, and bark.

Conservation Considerations: This sala-mander is currently known from only a fewlocations, all of which are on national forestsystem lands in the eastern San Gabriel Moun-tains. Until more information is obtained onthe distribution and abundance of this taxon,the few known localities warrant managementattention. If it is found to be more broadlydistributed, landscape-scale habitat manage-ment may suffice since its apparent nicheunder rocks, logs, and duff suggest it is notparticularly vulnerable to existing agents ofchange. Mesic lower montane forests (e.g.,bigcone Douglas-fir/canyon live oak) appearto be important to this species.

Tehachapi slender salamander(Batrachoseps stebbinsi)

Status and Distribution: The Tehachapislender salamander is a Forest Service Region5 Sensitive Species and is state-listed as threat-ened. The narrow known range of this speciesis primarily restricted to the Piute andTehachapi mountains of Kern County at el-evations between 2,500 and 5,000 feet (Zeineret al. 1988). There are no known locations ofthis species in the assessment area, but areasnear the Tehachapi Mountains that containpotential habitat include the Mount Pinos/Frasier Mountain area and also the north sidesof Liebre and Sawmill mountains.

Habitat: This salamander is found prima-rily in mixed pine-oak and riparian woodlandsin moist canyons, ravines, and north-facing

slopes. It is often found in association withrocky talus slopes (Zeiner et al. 1988).

Conservation Considerations: Surveys areneeded to determine if this species is presentin areas of potential habitat within the assess-ment area that are near known populations.

California spotted owl(Strix occidentalis occidentalis)

Status and Distribution: The Californiaspotted owl is a Forest Service Region 5 Sen-sitive Species. Spotted owls occur in all of themajor mountain ranges in the assessment area,although some ranges support very few pairs(fig. 4.24). They are found at elevations rang-ing from below 1,000 feet along the Montereycoast to approximately 8,500 feet (Stephenson1991). A territorial species with large acreagerequirements (at least 300 acres of mature for-est per pair), spotted owls in southernCalifornia are clustered in disjunct mountainand foothill areas where suitable habitat ex-ists. These clusters are surrounded by largeareas of unsuitable habitat.

Habitat: Spotted owls are found in ma-ture forests, typically where there is a dense,multi-layered canopy. Nest stands often havea well-developed hardwood understory (e.g.,canyon live oak) and a conifer overstory. How-ever, some high-elevation territories (above6,500 feet) consist primarily or solely of coni-fers and some low-elevation territories (below3,000 feet) are found in pure hardwood stands.Territory sizes vary widely depending on habi-tat type, with territories becoming larger inthe high-elevation, conifer-dominated sites.Verner et al. (1992) and LaHaye et al. (1997)provide detailed quantitative information onthe habitats occupied by spotted owls in south-ern California.

Conservation Considerations: Spottedowls in southern California are believed tofunction as a metapopulation, with separatesubpopulations connected by infrequent butpersistent interchange of individual owls(Noon and McKelvey 1992; LaHaye et al.1994). The largest subpopulation is the 200-plus territories in the adjacent San Bernardino

190

Figure 4.24. Known locations of the California spotted owl in the assessment area.

and San Gabriel mountains. Although CajonPass separates these two mountain ranges,there is not a major habitat discontinuity andonly 6 miles separate the easternmost SanGabriel territory from the westernmost SanBernardino territory. Noon and McKelvey(1992) stress the importance of this large sub-population as a likely source area that providesimmigrants to sustain the surrounding smaller,isolated subpopulations. However, the simu-lation modeling results of LaHaye et al. (1994)found the southern California spotted owlmetapopulation’s stability to be insensitive torates of dispersal between mountain ranges,suggesting that the subpopulations could beconsidered effectively isolated.

An important factor to consider is thatspotted owls occupy a variety of different habi-tats across the assessment area. Reproductivesuccess and survivorship rates for individualmembers of the population may differ, de-pending on which habitat type they inhabit(Pulliam et al. 1992). There is empirical evi-dence from the San Bernardino Mountainsthat spotted owl reproductive success is sig-nificantly higher in lower montane bigconeDouglas-fir/canyon live oak forests than it isin high-elevation montane conifer forests (table4.16) (LaHaye et al. 1997). These lower eleva-tion habitats are believed to be productivebecause of high woodrat densities (the owl’s pri-mary prey) in the surrounding chaparral.

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Chapter 4

Northern pygmy owl (Glaucidium gnoma)Status and Distribution: The northern

pygmy owl is a local species of concern be-cause it is rare in southern California and mostknown locations are within the assessmentarea. Garrett and Dunn (1981) report thatpygmy owls frequently occur in foothill can-yons and forested interior mountains of SanLuis Obispo and Santa Barbara counties butbecome considerably rarer as you move southand east. Sighting records described by Lentz(1993) suggests pygmy owls are fairly com-

Table 4.16. Reproductive success of spotted owls in the San Bernardino Mountains by habitat type(from LaHaye et al. 1997).

Number of nests Average fledglingsHabitat Type (% successful) per nest

Oak/bigcone Douglas-fir 42 (81%) 1.39

(low elevation)

Conifer/hardwood 21 (67%) 0.98

(middle elevation)

Mixed conifer 38 (76%) 0.95

(high elevation)

They also tend to be below the snow line ofmost late winter/spring storms, which mayreduce the impact of such weather events dur-ing the breeding season. Large, late-seasonstorms have been shown to have a major ef-fect on spotted owl reproductive success innorthwestern California (Franklin et al. inpress) and appear to have a similar effect inthe Sierra Nevada ( J. Verner, Pacific South-west Research Station, pers. comm.).

The apparent high quality of low-elevation live oak and bigcone Douglas-firdominated habitats may explain the contin-ued persistence of small spotted owlpopulations in each southern Californiamountain range. Maintaining these restrictedhabitats, which are often narrow stringers ofdense, mature forest on north-facing slopesand deep canyons, should be a high manage-ment priority. They are vulnerable to loss instand-replacing fires that move in from the sur-rounding chaparral.

mon near Big Pine Mountain, less commonaround Figueroa and Pine mountains, and rareon Mount Pinos. They reportedly occur in theSan Gabriel, San Bernardino, and San Jacintomountains, although detailed information ontheir distribution and abundance is lacking.They occur rarely if at all in the Santa AnaMountains, and they are described as “veryrare if not now extirpated” from San DiegoCounty (SDNHM 1998).

Habitat: Pygmy owls are found most com-monly in oak-conifer and riparian-coniferwoodlands, often in canyons (Garrett andDunn 1981). They can occur from low-elevation foothill canyons up into montaneconifer forests but reportedly become less com-mon above 6,000 feet (Zeiner et al. 1990).Pygmy owls typically nest in abandoned wood-pecker holes, especially those of the acornwoodpecker (Zeiner et al. 1990). They areoften found near forest openings.

Conservation Considerations: Lowermontane hardwood-conifer forests (e.g.,bigcone Douglas-fir/Coulter pine/live oak as-sociations) may be particularly important tothis species. There are indications that theseforests are declining due to an increase instand-replacing fires (see “Fire” section inchapter 3).

Purple martin (Progne subis)Status and Distribution: Purple martins

occurred, at least historically, in all of the ma-jor mountain ranges in the assessment area.However, many historic localities are no longer

192

Animals of Montane ConiferForest Habitats

Animals species associated with montaneconifer forests that received individual con-sideration in this assessment include threeinvertebrates, six reptiles (table 4.17), ninebirds, and seven mammals (table 4.18). Noneof these species is federally listed as threatenedor endangered, which is a reflection of lowerrates of habitat loss in montane areas that arepredominately on public lands.

occupied (Garrett and Dunn 1981; Unitt1984). Three known nesting sites on PalomarMountain were abandoned in the mid-1980s(R. Higson, pers. comm., 1997). They alsohave reportedly disappeared from most of theSan Gabriel Mountains and may no longerbreed there (D. Cooper, UC Riverside, in litt.,1998).

Within the Los Padres National Forest,Lentz (1993) and Lehman (1994) describe ob-servations of purple martins on Big PineMountain and San Rafael Mountain in the1980s, but it is unclear if these sites are stilloccupied. Nojoqui Falls County Park and theAlisal Ranch area in the Santa Ynez Valley arethe most recently documented breeding sites(Lehman 1994).

In the San Jacinto Mountains, LakeHemet and Garner Valley are historic breed-ing localities and there are indications thatpurple martins may still occur there (D. Free-man, unpubl. notes). In San Diego County,recent known sites include Palomar Observa-tory, Cuyamaca Peak, and Kitchen Creek Road(SDNHM 1998).

Habitat: Purple martins develop colonialnests in cavities of large trees in oak or ripar-ian woodlands and low-elevation coniferousforests (Garrett and Dunn 1981). Nests areoften located in a tall, old isolated tree or snagin open forest or woodland, frequently near abody of water (Zeiner et al. 1990).

Conservation Considerations: Competi-tion for nest cavities from European starlingshas taken a heavy toll on the purple martin(Garrett and Dunn 1981; Unitt 1984;Lehman 1994). It is also negatively affectedby declines in snag densities. More informa-tion is needed on locations of active purplemartin colonies in the assessment area. Occu-pied sites should be given site-specificattention as this species is highly vulnerableto extirpation from individual mountainranges and the entire assessment area. Starlingcontrol in the vicinity of active nest sites is apotential habitat improvement action.

Cassin’s solitary vireo(Vireo solitarius cassinii)

Status and Distribution: The Cassin’s soli-tary vireo is a local species of concern becauseit is uncommon in southern California andmost known breeding locations are within theassessment area. It is broadly distributed alongthe coastal slopes of the mountains in foothilland lower montane forests and woodlands,particularly in densely wooded canyons(Garrett and Dunn 1981). BBS results from1980 to 1996 show solitary vireos increasingstatewide at a statistically significant rate of3.6 percent a year (Sauer et al. 1997). Resultsfrom the Forest Service riparian bird study alsoshow an increasing trend of 10.3 percent a yearin the southern California national forests.

Habitat: The Cassin’s solitary vireo breedsin oak and mixed hardwood-conifer wood-lands. Lentz (1993) says that this subspeciesis encountered on the Los Padres NationalForest in shaded areas where oaks and coni-fers form a canopy, often near riparianvegetation.

Conservation Considerations: Solitaryvireos frequently have their nests parasitizedby brown-headed cowbirds (Verner and Boss1980; Erhlich et al. 1988). The taxonomy ofsolitary vireos needs to be clarified. Recentstudies suggest that the Cassins and Plumbeussubspecies should be recognized as distinctspecies (Johnson 1995).

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Chapter 4

Montane Conifer InvertebratesBicolored rainbeetle (Pleocoma bicolor)

Status and Distribution: The bicoloredrainbeetle is a species of local concern becauseit is endemic to a small portion of the SanBernardino Mountains. The entire knownrange of this species is confined to an areaextending from Rim of the World Drive(Highway 18) near the Crestline cutoffthrough Crestline, Bluejay, and ArrowheadCity to the north shore of Lake Arrowhead(Hovore 1991). Most of this area is privateland where there has been intensive recre-ational and housing development in the pasttwo decades. This rainbeetle has declined andpossibly has been extirpated from much of itshistorical range (Hovore 1991).

Table 4.17. Invertebrates and reptiles associated with montane conifer forests that receivedindividual consideration. Displayed for each species: (1) the level of knowledge about where it occurs insouthern California and, in parentheses, the estimated percentage of locations that are on national forest systemlands; (2) the mountain subareas occupied (y = occurs in breeding season, h = historically occurred, p = potentiallyoccurs, t = transient, w = winter visitor)—if the species is localized and data are available, the approximate numberof occurrences may be displayed; (3) the vulnerability of populations on national forest system lands to existingthreat factors; (4) population trends; and (5) the assigned conservation category.

Montane ConiferForest Animals ofConcern federal status

(1)Knowledge

of SoCalLocations

(% on NFs)

(5)Conser-vation

Category

(4) Pop.Trend

(3)Vulner-ability

on NFs

(2) areas occupied or estimated # of occurrences if spp. localized

San Bern. NFCleveland NF Angeles NF Los Padres NFSan

DiegoRngs

SanJacMts

SntaAnaMts

SanBernMts

No.SL

Rng

So.SL

Rng

SanGabMts

Cas-taic

Rngs

So.LP

Rngs

Invertebrates

Bicolored rainbeetle Low y Mod Unkn Landscape(0-30%) level

Andrew’s marble Mod y Unkn Unkn Landscape butterfly (40-80%) level

August checkerspot Mod y Unkn Unkn Landscape(> 70%) level

Reptiles

Sagebrush lizard Mod y y y y p y y Low Unkn Landscape(50-70%) level

Southern rubber boa Mod y y y* Mod Unkn Landscape(30-70%) level

Coastal mtn. kingsnake Mod y y p y Mod Unkn Landscape(40-70%) level

San Bernardino mtn. Mod y y y Mod Unkn Landscape kingsnake (50-80%) level

San Diego mtn. Mod y y High Unkn Landscape kingsnake (40-70%) level

Mountain garter snake Low y Low Unkn Landscape(> 60%) level

* Rubber boas near Mount Pinos are intergrades between southern and northern subspecies

Habitat: We have no specific informationon the habitat associations of this species. Mostof the area within its small geographic rangeis either pine forest, mixed conifer forest, orblack oak woodland.

Conservation Considerations: Informa-tion is needed on the current distribution ofthe species. It would be particularly useful toknow the extent to which it occurs on publiclands in the San Bernardino Mountains. If notwell represented on existing public lands, ar-eas known to still harbor this species shouldbe considered for land exchanges and/or ac-quisitions.

194

Montane ConiferBirds & Mammalsof Concern federal status

(1)Knowledgeof SoCalLocations

(% on NFs)

(5)Conser-vation

Category

(4) Pop.Trend

(3)Vulner-ability

on NFs

(2) areas occupied or estimated # of occurrences if spp. localized

San Bern. NFCleveland NF Angeles NF Los Padres NFSan

DiegoRngs

SanJacMts

SntaAnaMts

SanBernMts

No.SL

Rng

So.SL

Rng

SanGabMts

Cas-taic

Rngs

So.LP

Rngs

Table 4.18. Birds and mammals associated with montane conifer forests that received individualconsideration. Displayed for each species: (1) the level of knowledge about where it occurs in southern Californiaand, in parentheses, the estimated percentage of locations that are on national forest system lands; (2) themountain subareas occupied (y = occurs in breeding season, h = historically occurred, p = potentially occurs,t = transient, w = winter visitor)—if the species is localized and data are available, the approximate number ofoccurrences may be displayed; (3) the vulnerability of populations on national forest system lands to existing threatfactors; (4) population trends; and (5) the assigned conservation category.

1 based on USFS riparian point count results2 Bell’s vireo is increasing regionwide, but decreasing on national forest service lands

BirdsSharp-shinned hawk Low w w y y y w p w y Mod Unkn Landscape

(> 60%) level

Northern goshawk Low y y p y Mod Unkn Site(60-80%) specific

Mt Pinos blue grouse Low h/p Mod Unkn Site(> 90%) specfic

Flammulated owl Mod p y y y p y y High Unkn Landscape(40-60%) level

Northern saw-whet owl Mod y p y y y p y p y Mod Unkn Landscape(> 60%) level

Williamson’s sapsucker Mod w y y y w y w Mod Unkn Landscape(> 60%) level

White-headed Mod y y y y p y p p Mod Unkn Landscape woodpecker (> 60%) level

Hermit thrush Mod p/w w p y y w y w y Mod Unkn Landscape(> 50%) level

Virginia’s warbler Mod t t t y y t t t t Low Unkn Landscape(> 60%) level

MammalsLong-eared myotis Mod y y y y p y p Unkn Unkn Landscape

(> 50%) level

Fringed myotis Mod y y y y p y p Unkn Unkn Landscape(> 50%) level

Long-legged myotis Mod y y y y p y p Unkn Unkn Landscape(> 50%) level

Golden-mantled Mod y Low Unkn Landscape ground squirrel (> 70%) level

San Bernardino Mod h/p y p Mod Unkn Landscape flying squirrel (> 60%) level

San Bernardino white- Low h/p p Unkn Unkn Site eared pocket mouse (> 60%) specific

Porcupine Low y h/p Unkn Unkn Landscape(> 60%) level

Andrew’s marble butterfly(Euchloe hyantis andrewsi)

Status and Distribution: The Andrew’smarble is a former C2 Candidate for federallisting. Its geographic range is restricted to the

San Bernardino Mountains (Murphy 1990).It is found at elevations above 5,000 feet nearLake Arrowhead and Big Bear Lake, and inother locations across the crest and north slope.Recent records include Baldwin Lake,

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Chapter 4Sugarloaf Mountain, and Wild Horse Meadow(Murphy 1990).

Habitat: The Andrew’s marble is foundprimarily in pine and mixed conifer forests.The larval host plants for this subspecies areStreptanthus bernardinus and Arabis holboellii(Murphy 1990).

Conservation Considerations: No threatshave been identified for this species. Murphy(1990) considered the Andrew’s marble to bea category D taxon, which is defined as beingneither in danger of extinction nor likely tobe. It is not clear what this determination isbased upon, other than that the Andrew’smarble appears to be well distributed andlargely on national forest system lands.

August checkerspot butterfly(Euphydryas editha augustina)

Status and Distribution: This high-elevation relative of the quino checkerspot isa species of local concern because it is endemicto the San Bernardino Mountains. The Au-gust checkerspot has been found above 8,000feet on Sugarloaf Peak and along forest roadsand meadows from 5,000 to 7,000 feet nearRunning Springs, Moonridge, CedarpinesPark, Wild Horse Creek, and Fawnskin(Emmel and Emmel 1973).

Habitat: The August checkerspot occursin pine and mixed conifer forests. Collinsiachildii is a known host plant and it is reportedthat Castilleja species are also used (Emmeland Emmel 1973).

Conservation Considerations: No threatshave been identified for this species. Similarin known range and habitat to the Andrew’smarble, the August checkerspot probablywould be similarly described as being neitherin danger of extinction nor likely to be.

Montane Conifer ReptilesSagebrush lizard (Sceloporus graciosus)

Status and Distribution: The sagebrushlizard is considered a species of local concernbecause it is patchily distributed and restrictedto high elevations (primarily above 4,000 feet).Two subspecies occur in the assessment area.

The southern sagebrush lizard, S. g.vandenburgianus, extends from near MountPinos south to the Sierra San Pedro Martir inBaja California. The western sagebrush lizard,S. g. gracilis, occurs in the Mount Pinos re-gion and extends north into the Sierra Nevadaand along the central and northern Califor-nia coast (Censky 1986).

S. g. gracilis has a very patchy distributionin small islands of upper-elevation habitat thatlie within the Los Padres National Forest.Occupied areas include Mount Pinos, PineMountain, Big Pine Mountain, Sierra MadreMountains, and Cone Peak in the northernSanta Lucia Range (J. Copp, Cal. Academyof Sciences, in litt.). It appears to be absentfrom the low-elevation southern Santa LuciaRange (Censky 1986).

Fisher and Case (1997) report that S. g.vandenburgianus was the most frequently cap-tured species in pitfall trap arrays in the vicinityof Big Bear Lake in the San Bernardino Moun-tains and the second most frequently capturedspecies at the James Reserve in the San JacintoMountains. It also occurs in the San GabrielMountains and the higher-elevation moun-tains in San Diego County.

Habitat: Sagebrush lizards inhabit a vari-ety of montane vegetation types includingmixed conifer forest, black oak woodlands,montane chaparral, and pinyon-juniper wood-lands (Zeiner et al. 1988). In general, they tendto be in open habitats that receive consider-able sunlight.

Conservation Considerations: No threatfactors have been specifically identified forsagebrush lizards, other than the fact that theirdistribution in southern California is limitedand highly disjunct. They should be ad-equately conserved through landscape-scalehabitat management.

Southern rubber boa(Charina bottae umbratica)

Status and Distribution: The southernrubber boa is state listed as threatened and is aForest Service Region 5 Sensitive Species. It isfound in the San Bernardino and San Jacinto

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Figure 4.25. The approximate range of the southern rubber boa.

mountains, at elevations between 4,900 and7,900 feet (fig. 4.25) (Stewart 1988). Thereare approximately eight known localities in theSan Jacinto Mountains (including Fern Val-ley, Dark Canyon, Devil’s Slide trail, and theNorth Fork, San Jacinto River near the High-way 243 crossing) and thirty-five to fortyknown locations in the San Bernardino Moun-tains (Keasler 1981; Loe 1985; Stewart 1988).Twenty-six of the localities in the San Bernar-dino Mountains are in a 10-mile-long stripbetween Twin Peaks on the west and GreenValley on the east (Stewart 1988). Other lo-cations include Barton Flats and north-facingslopes immediately south of Big Bear Lake.

Isolated populations of rubber boas havealso been found in the southern Los Padresranges on Mount Pinos, Mount Abel, andAlamo Mountain (Alten and Keasler 1978).Morphological and electrophoretic analysis ofspecimens from these mountains show themto be intergrades between the southern rubberboa and the northern rubber boa (C. b. bottae)which occurs in the Sierra Nevada range (G.Stewart, Cal Poly Pomona, in litt.).

Habitat: The southern rubber boa usuallyoccurs in moist woodlands and coniferous for-ests. It tends to be associated with vegetativelyproductive sites, usually with deep, well-developed soils (Loe 1985). It is a burrower

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Conservation Considerations: The rub-ber boa is vulnerable to habitat loss fromdevelopment on private land, water diversionor extraction, and land use activities that de-stroy soil or surface cover. The majority ofknown rubber boa locations are on privatelands. The lush, mesic forests that are primehabitat for this species tend to be highly inter-spersed with private lands (e.g., around LakeArrowhead and Idyllwild). Where such forestconditions occur on public land, care shouldbe taken to maintain mesic conditions, downlogs, and leaf cover.

California mountain kingsnake(Lampropeltis zonata)

Status and Distribution: Three separatesubspecies of mountain kingsnakes occurwithin the assessment area. The San Diegosubspecies, L. z. pulchra, is a Forest ServiceRegion 5 Sensitive Species and a CaliforniaSpecies of Special Concern. It occurs in themountains of San Diego County (Laguna,Cuyamaca, Volcan, Hot Springs, andPalomar), and the Santa Ana and SantaMonica mountains (Jennings and Hayes1994). Although most common in montaneforests, L. z. pulchra is also found at low eleva-tions in foothill canyons (McGurty 1988).There are scattered historic reports of this sub-species near sea level along the coast, but itwas not detected during recent reptile surveyson Camp Pendleton, the largest remainingstretch of undeveloped coastal habitat in south-ern California (Holland and Goodman 1998).

The San Bernardino subspecies, L. z.parvirubra, is also a Forest Service SensitiveSpecies and a California Species of SpecialConcern. It occurs in the San Jacinto, SanBernardino, and San Gabriel mountains. Thedocumented elevation range for this subspe-

and also commonly makes use of rock out-crops as hibernacula. Large downed logs anda well-developed litter/duff layer are consid-ered important for cover and for maintaininghigh soil moisture. Soil moisture may be a lim-iting factor for rubber boas, as they are usuallyfound during summer months in damp drawsnear springs, seeps, and streams (Loe 1985).

cies extends from 1,200 feet in Eaton Can-yon (San Gabriel Mountains) to 8,100 feeton Mount San Jacinto (Jennings and Hayes1994). Finally, the coastal mountainkingsnake, L. z. multifasciata, which is notidentified as a sensitive species, is found in thesouthern Los Padres ranges and the northernSanta Lucia Range (Zweifel 1975).

Habitat: In southern California, moun-tain kingsnakes appear to be most commonin relatively open stands of ponderosa pine,Jeffrey pine, Coulter pine, and/or black oakat elevations between 4,500 and 6,500 feet(McGurty 1988). They occur at higher eleva-tions as well but are less common. Mountainkingsnakes also occur at lower elevations be-low the montane conifer belt, where they arefound in riparian or mesic oak woodlandscharacterized by sycamore, cottonwood, andcoast live oak. This is the type of habitat wheremountain kingsnakes are primarily found inthe Santa Ana and Santa Ynez mountains(McGurty 1988; Fisher and Case 1997). Well-illuminated canyons with rocky outcrops inassociation with bigcone Douglas-fir are alsogood habitat.

Partially shaded rock outcrops appear tobe an important microhabitat element for refu-gia and basking sites (McGurty 1988). Largedowned logs also may be important (Hollandand Goodman 1998).

Conservation Considerations: The big-gest threat to mountain kingsnakes is poachingby collectors and the destruction of microhabi-tat caused by this activity (e.g., dismantlingrock outcrops and shredding down logs)(Jennings and Hayes 1994). There is a signifi-cant illegal commercial trade in this attractivesnake that creates a demand for poaching.McGurty (1988) documents a decline in theabundance of mountain kingsnakes on LagunaMountain in San Diego County that he at-tributes to illegal collecting.

Mountain garter snake(Thamnophis elegans elegans)

Status and Distribution: The mountaingarter snake is a taxon of local concern because

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Montane Conifer BirdsSharp-shinned hawk (Accipiter striatus)

Status and Distribution: The sharp-shinned hawk is a California Species of SpecialConcern. It occurs regularly in winter and asa migrant throughout the assessment area, butnesting has been recorded only in the north-ern Santa Lucia, San Gabriel, San Bernardino,and San Jacinto mountains. It is not known ifnesting occurs regularly in these mountains,although summer siting records in the SanBernardino and San Jacinto mountains arecommon enough to suggest it does (Garrettand Dunn 1981). Reported historic nestinglocalities include Icehouse Canyon in the SanGabriel Mountains and Lake Arrowhead andBig Bear Valley in the San Bernardino Moun-tains (Garrett and Dunn 1981).

Habitat: Sharp-shinned hawks nest in co-niferous forests often within riparian areas oron north-facing slopes. Nest stands are typi-cally dense patches of small-diameter treeswhich are cool, moist, well shaded, with littleground cover, and near water (Zeiner et al.1990). These stands are often in close prox-imity to open areas.

Habitat: Goshawks can occur in a varietyof coniferous forest communities, includingponderosa and Jeffrey pine, mixed conifer,white fir, and lodgepole pine. Nest stands aretypically composed of large, densely spacedtrees, with higher canopy closure and moreopen understories than the surrounding land-scape (Woodbridge and Detrich 1994). Whenforaging, goshawks are forest generalists, us-ing a variety of forest types, structuralconditions, and successional stages (Reynoldset al. 1992).

Large snags and downed logs are believedto be important habitat elements because they

it occurs only in the San Bernardino Moun-tains (Fitch 1983). It is found at elevationsabove 4,900 feet (Fisher and Case 1997b).Information is scarce on the status of thissubspecies; we found no locality informa-tion for it.

Habitat: Although not as aquatic in habitas the two-striped garter snake, the mountaingarter snake is typically found in the vicinityof permanent or semi-permanent sources ofwater in a variety of habitats (Zeiner et al.1988).

Conservation Considerations: More in-formation is needed on the distribution andabundance of this snake in the San Bernar-dino Mountains. The most mesic portion ofthis range is also where private land is con-centrated (i.e., Crestline to Lake Arrowhead),so it is possible that the mountain garter snakeis poorly represented on public lands.

Conservation Considerations: More in-formation is needed on where sharp-shinnedhawks nest, particularly in the San Bernardinoand San Jacinto mountains. The breedingpopulation in the southern California moun-tains is likely small and could easily beextirpated by cumulative disturbances nearnesting sites. Large stand-replacing fires are asignificant threat, but this hawk’s preferencefor early-seral forest stands indicates it wouldprobably benefit from small-scale disturbancesthat spur regeneration.

Northern goshawk (Accipiter gentilis)Status and Distribution: The northern

goshawk is a Forest Service Region 5 Sensi-tive Species and a California Species of SpecialConcern. Rare in southern California, gos-hawks have been observed during the breedingseason only on Mount Abel, Mount Pinos, andin the San Bernardino and San Jacinto moun-tains (fig. 4.26) (Garrett and Dunn 1981;Lentz 1993). A pair with two young were ob-served in the vicinity of Mount Abel in June1989 and an adult and one immature birdwere observed at Mount Pinos in July 1991(Lentz 1993). Mid-summer localities in theSan Jacinto Mountains include Tahquitz Val-ley, Willow Creek, Skunk Cabbage, HumberPark, and Lake Fulmor (Garrett and Dunn1981). Breeding has not been documented inthe San Bernardino Mountains, although gos-hawks have been observed near Big Bear Lake,Arrowbear (Garrett and Dunn 1981), and onFish Creek.

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Figure 4.26. Documented locations of northern goshawk in the assessment area.

increase the abundance of small- to medium-sized birds and mammals that goshawks eat(Reynolds et al. 1992). Goshawks have largearea requirements; in the southern CascadeMountains of northern California, goshawkterritories were spaced at intervals of one per1,500 to 2,400 acres of conifer forest habitat(Woodbridge and Detrich 1994).

Conservation Considerations: More in-formation is needed on where goshawks nestin the southern California mountains. Thebreeding population is clearly small, probablyfewer than thirty pairs, and could easily be ex-tirpated by impacts to nesting sites. Efforts tomaintain the integrity of these sites cannot bemade until we know where they are. Protec-

tion of mature conifer forest habitats fromstand-replacing fire will be important to main-taining goshawks in this region.

Mount Pinos blue grouse(Dendragapus obscurus)

Status and Distribution: The MountPinos blue grouse is a species of local concernbecause of its extremely localized distributionthat lies entirely within the assessment area. Itis known only from areas above 6,500 feet inthe Mount Pinos/Mount Abel area, with theexception of one outlying record of grousechicks from Big Pine Mountain in the 1930s(Lentz 1993). Dicky and van Rossem (1923)described the grouse of the southern Sierra

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Habitat: Flammulated owl breeding habi-tat in southern California typically consists ofopen, mature Jeffrey or ponderosa pine for-ests intermixed with black oak (Garrett andDunn 1981). The owls occur less frequentlyin white fir dominated stands (Zeiner et al.1990) and probably only where at least somelarge pines are present (Hayward and Verner1994). Flammulated owls are typically foundin xeric mid-slope or ridgetop forests that havean open, park-like quality. They are second-ary cavity nesters, and black oaks may beimportant sources of suitable cavities for them(Marcot and Hill 1980).

Conservation Considerations: Open, ma-ture pine forests have declined in extent in themountains of southern California due to his-toric logging practices, reduced firefrequencies, and the development associatedwith expanding mountain communities. Thecurrent lack of low- to moderate-intensityunderstory fires in montane conifer forests iscausing a shift in species composition awayfrom pines and black oak and towards whitefir and incense cedar (see “Fire” section inchapter 3). The flammulated owl, perhapsmore than any other species, is imperiled bythis trend.

Northern saw-whet owl (Aegolius acadicus)Status and Distribution: The northern

saw-whet owl is a local species of concern be-cause its breeding population in southernCalifornia is small and primarily restricted tomontane conifer forests. However, it does havea fairly wide elevation range, extending fromover 8,000 feet down to to almost 3,000 feet(SDNHM 1998), which may explain why it’smore widely distributed than the flammulatedowl.

Saw-whet owls occur in the northern SantaLucia Mountains and on Figueroa, Big Pine,Pine, and Pinos mountains in the southernLos Padres (Lentz 1993; Lehman 1994). Theyalso nest in the San Gabriel, San Bernardino,

Nevada and Mount Pinos as a distinct sub-species, D. o. howardi, citing eight specimensfrom the area.

It is unclear if blue grouse still occur inthis region. Lentz (1993) describes severalunconfirmed sightings near Sawmill Moun-tain (just west of Mount Pinos) in the early1990s, but she says the last verified recordsare from 1976 and 1979. If they do still occurin the area, the population appears to be verysmall.

Habitat: Blue grouse inhabit high-eleva-tion coniferous forests and especially favordense stands of firs on north-facing slopes(Garrett and Dunn 1981).

Conservation Considerations: Surveys areneeded to determine if blue grouse still occurin the Mount Pinos/Mount Abel area. Thepersistence of grouse in this area is probablymost threatened by the limited amount ofsuitable habitat and the stochastic problemsfaced by small, isolated populations. Land useactivities do not appear to be a threat. Mostof the area is within the Chumash WildernessArea and the type of dispersed recreationalactivity occurring there should not apprecia-bly impact the grouse population.

Flammulated owl (Otus flammeolus)Status and Distribution: The

flammulated owl is a species of local concernbecause its breeding distribution in southernCalifornia is patchy and restricted to montaneforests within the assessment area. It nests atelevations between 5,500 and 8,200 feet pri-marily in the San Gabriel, San Bernardino,and San Jacinto mountains (fig. 4.27) (Win-ter 1974; Garrett and Dunn 1981). A few nestin the Mount Pinos area and possibly on BigPine Mountain (Lentz 1993). They also oc-cur down to 4,000 feet in the northern SantaLucia Range. In the San Diego ranges,flammulated owls are occasionally observed insummer in the Palomar, Cuyamaca, or Lagunamountains, but nesting has not been docu-mented (Unitt 1984; SDNHM 1998).

Recent surveys have detected fifteen totwenty-five flammulated owl locations in the

San Bernardino Mountains and five to ten lo-cations in the San Jacinto Mountains (R.McKernan, SBNHM, unpubl. data).

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Figure 4.27. Documented locations of flammulated owls in the assessment area.

and San Jacinto mountains, and the highermountains of San Diego County (Garrett andDunn 1981; Unitt 1984).

Habitat: Saw-whet owls most commonlybreed in dense pine and fir forests that havean oak understory (Garrett and Dunn 1981;Lehman 1994).

Conservation Considerations: Stand-replacing wildfire in dense montane coniferforests is probably the biggest threat to saw-whet owls.

Williamson’s sapsucker(Sphyrapicus thyroideus)

Status and Distribution: TheWilliamson’s sapsucker is a local species of

concern because its breeding population insouthern California is small, highly disjunct,and restricted to high elevation forests. On theLos Padres National Forest, Williamson’s sap-suckers nest in small numbers on Mount Pinosand Mount Abel, and possibly on Pine Moun-tain (Lentz 1993). They also breed in the SanGabriel, San Bernardino, and San Jacintomountains. The greatest concentration ofbreeding birds is in the San Bernardino Moun-tains on the north-facing slopes behind BigBear Lake and in the vicinity of Mount SanGorgonio (Garrett and Dunn 1981).Williamson’s sapsuckers are more widely dis-tributed in montane conifer forests during the

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winter. There is no local information on popu-lation trends for this species.

Habitat: Williamson’s sapsuckers breed athigh elevations in coniferous forests domi-nated by white fir or lodgepole pine (Garrettand Dunn 1981). In the southern Californiamountains, they are typically found on north-facing slopes.

Conservation Considerations: Breedinghabitat for Williamson’s sapsuckers is prob-ably most threatened by the risk of large,stand-replacing fire. Habitat in each occupiedmountain range is very limited in extent andvulnerable to loss in a single, large fire event.

White-headed woodpecker(Picoides albolarvatus gravirostris)

Status and Distribution: The white-headed woodpecker is a local species ofconcern because its breeding population insouthern California is small and restricted tomontane conifer forests. Southern Californiapopulations of this species are also consideredto be a distinct, endemic subspecies (Kratter1992). The white-headed woodpecker occursin all of the mountain ranges that containmontane conifer forests. There is no local in-formation on population trends for thisspecies.

Habitat: White-headed woodpeckers arefound in mixed conifer forests dominated bylarge-coned pines such as Coulter, sugar, Jef-frey and ponderosa; they range only marginallyinto associations dominated by white fir orlodgepole pine (Garrett and Dunn 1981).

Conservation Considerations: Similar tothose described for the flammulated owl.White-headed woodpeckers are closely asso-ciated with mature pine trees, which appearto be declining in many areas of southernCalifornia’s mountains.

Hermit thrush (Catharus guttatus)Status and Distribution: The hermit

thrush is a local species of concern because itsbreeding population in southern California issmall, disjunct, and primarily restricted tohigh-elevation conifer forests. It does nest at

relatively low elevations in the northern SantaLucia Mountains, but elsewhere breeds mainlyabove 6,000 feet. Small breeding populationsexist in the higher mountains of the southernLos Padres. The thrush is most numerous inthe San Gabriel and San Bernardino moun-tains but also probably breeds in the SanJacinto Mountains (Garrett and Dunn 1981).In San Diego County there are only fourbreeding-season records, one each on Palomar,Hot Springs, Volcan, and Cuyamaca moun-tains (SDNHM 1998). It is considerably morewidespread in winter.

Habitat: Hermit thrushes in southernCalifornia breed primarily in forests domi-nated by white fir. They are usually found onsteep, north-facing slopes (Garrett and Dunn1981).

Conservation Considerations: Stand-re-placing wildfire in dense montane coniferforests is probably the biggest threat to her-mit thrushes. Otherwise, the densification offorest stands caused by the exclusion of low-to moderate-intensity fires is probably increas-ing the amount of suitable habitat for thisspecies.

Virginia’s warbler (Vermivora virginiae)Status and Distribution: The Virginia’s

warbler is a California Species of Special Con-cern and an extremely rare breeder in southernCalifornia. Within the assessment area, breed-ing has been documented only in the SanGabriel and San Bernardino mountains. Thewarbler has been observed in the summer inthe Blue Ridge area on the northeastern endof the San Gabriel Mountains (D. Cooper, UCRiverside, in litt.), and at 6,900 feet alongArrastre Creek and at 6,000 feet along theSouth Fork of the Santa Ana River in the SanBernardino Mountains (Johnson and Garrett1974).

Habitat: In the breeding season Virginia’swarblers occupy brushy areas (e.g., mountainmahogany, manzanita, and serviceberry)within arid coniferous forest (Garrett andDunn 1981).

Conservation Considerations: More in-formation is needed on the breeding

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Chapter 4distribution of this species in the assessmentarea. However, the habitats occupied byVirginia’s warblers are not highly vulnerableto existing land use activities.

Montane Conifer MammalsLong-eared myotis bat (Myotis evotis)

Status and Distribution: The long-earedmyotis was a C2 candidate species for federallisting before that designation was discontin-ued. Its distribution in southern Californiaappears to be restricted to high-elevation habi-tats. This bat was found in the assessment areaat fifteen of seventy-six sites surveyed for batsfrom 1996 to 1998 (Simons et al. in prep.).Localities include Indian Creek (at BluffCamp) and Pine Springs (north of CuddyValley) on the Los Padres National Forest;Dorr Canyon Spring, Islip Saddle, and BigRock Campground on the Angeles NationalForest; Arrastre Creek, Holcomb Valley, Al-pine Canyon, and Coon Creek on the SanBernardino National Forest; and the Lagunaand Cuyamaca mountains within the Cleve-land National Forest and adjoining CuyamacaRancho State Park. Long-eared myotis batswere found only at elevations above 4,000 feetand most were in conifer forests.

Habitat: Long-eared myotis bats can oc-cur in a variety of habitats, but are usuallyassociated with coniferous forests. They roostunder exfoliating tree bark, in tree hollows,caves, mines, cliff crevices, and rocky outcrops(Vonhof and Barclay 1996). They also some-times roost in buildings and under bridges.

Conservation Considerations: Protectionof conifer forest habitats from stand-replac-ing fire will be important to maintaininglong-eared myotis populations in the south-ern California mountains. The ability of thisspecies to roost in a wide variety of sites mayhelp reduce its vulnerability to human activi-ties.

Fringed myotis bat (Myotis thysanodes)Status and Distribution: The fringed

myotis was a C2 candidate species for federallisting before that designation was discontin-ued. Its distribution in southern California

appears to be restricted to high-elevation habi-tats. This bat was found in the assessment areaat ten of seventy-six sites surveyed for bats from1996 to 1998 (Simons et al. in prep.). Locali-ties include Frazier Mountain and Pine Springs(north of Cuddy Valley) on the Los PadresNational Forest, Buckhorn and Big Rockcampgrounds on the Angeles National For-est, Arrastre Creek on the San BernardinoNational Forest and Laguna Mountain on theCleveland National Forest. Fringed myotisbats were found only at elevations above 4,600feet, primarily in montane conifer forests butalso in pinyon-juniper woodland.

Habitat: Fringed myotis bats reportedlyoccur in a wide variety of habitats but are mostcommonly found in dry pine or mixed coni-fer forests and in pinyon-juniper woodlands.Caves, buildings, mine shafts, rock crevices incliff faces, trees, and bridges are used for ma-ternity and night roosts, while hibernation hasonly been documented in buildings and mines(Bradley and Ports 1998). On Laguna Moun-tain, these bats were observed roosting in cliffcrevices along the eastern escarpment (Minerand Brown 1996).

Conservation Considerations: Same asthose described for the long-eared myotis,with the addition that abandoned minesmay provide important hibernacula for thisspecies and efforts are needed to identifymines that are used and protect them fromhuman disturbance.

Long-legged myotis (Myotis volans)Status and Distribution: The long-legged

myotis was a former C2 candidate species forfederal listing before that designation was dis-continued. Its distribution in southernCalifornia appears to be restricted to high-el-evation habitats. This bat was found in theassessment area at twelve of seventy-six sitessurveyed for bats from 1996 to 1998 (Simonset al. in prep.). Localities include FrazierMountain and Chief Peak (just north of Ojai)on the Los Padres National Forest; Dorr Can-yon Spring and Buckhorn and Big Rockcampgrounds on the Angeles National Forest;

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Habitat: The San Bernardino flying squir-rel is known from mid- to upper-elevationconiferous forest habitats. Distributional in-formation from spotted owl pellets indicatesthat flying squirrels do not inhabit lower mon-tane bigcone Douglas-fir/canyon live oakforests. Flying squirrels use cavities in largetrees, snags, and logs for cover. Habitats aretypically mature, dense conifer forest, particu-larly those containing white fir, in closeproximity to riparian areas (Zeiner et al.1990b).

Conservation Considerations: The appar-ent disappearance of flying squirrels from theSan Jacinto Mountains and their limited dis-tribution in upper elevation forests give riseto concerns about their vulnerability in theSan Bernardino Mountains. They appear to

Big Bear Lake Dam and Holcomb, Deep, andArrastre creeks on the San Bernardino Na-tional Forest; and Laguna Mountain and LostValley (north of Hot Springs Mountain) onthe Cleveland National Forest. All but one ofthe locations where long-legged myotis batswere found were at elevations above 4,500 feet.

Habitat: The long-legged myotis is pri-marily a bat of coniferous forests but alsooccurs seasonally in riparian and desert habi-tats. It uses abandoned buildings, cliff crevices,exfoliating tree bark, and hollows within snagsas summer day roosts; caves and mine tunnelsas hibernicula (Bogan et al. 1998c).

Conservation Considerations: Same asthose described for the fringed myotis.

Golden-mantled ground squirrel(Spermophilus lateralis)

Status and Distribution: The golden-mantled ground squirrel is a local species ofconcern because in southern California it isfound only in the San Bernardino Mountains.The population in these mountains is consid-ered to be a distinct subspecies, S. l.bernardinus (Bartels and Thompson 1993). Itranges in elevation from approximately 6,000feet to over 10,000 feet (Williams 1986).

Habitat: Golden-mantled ground squir-rels inhabit a wide variety of montane habitatsfrom the upper edge of the pinyon belt toabove timberline. They are most common inopen, well-illuminated forests with a mix oftall trees, brush, and open ground supportingherbaceous plants (Williams 1986; Bartels andThompson 1993).

Conservation Considerations: This spe-cies does not appear to be sensitive to land useactivities; it is typically common around camp-grounds and buildings and invades loggedtimber stands (Bartels and Thompson 1993).It could be negatively affected by the trendtoward increasingly dense forests, but thegolden-mantled ground squirrel population inthe San Bernardino Mountains seems to belarge and well distributed in a variety of plantcommunities.

San Bernardino flying squirrel(Glaucomys sabrinus californicus)

Status and Distribution: The San Bernar-dino flying squirrel is a Forest Service Region5 Sensitive Species and a California Species ofSpecial Concern. It occurs in the San Bernar-dino Mountains and, at least historically, inthe San Jacinto Mountains. Williams (1986)lists its elevation range as between 5,200 and8,500 feet. Flying squirrels are preyed uponby spotted owls, and the best information wehave on the distribution of this squirrel comesfrom an analysis of spotted owl pellets whichwere collected throughout the San BernardinoMountains (fig. 4.28) (W. LaHaye, unpubl.data). These data suggest that flying squirrelsare widespread within the general elevationalrange reported by Williams.

Grinnell and Swarth (1913) captured asingle flying squirrel near Idyllwild in the SanJacinto Mountains, and there reportedly areseveral other old museum specimens from thisrange (Williams 1986). However, there havebeen no recent sightings. Analysis of a sub-stantial number of owl pellets from the SanJacinto Mountains did not turn up any flyingsquirrel remains (W. LaHaye, unpubl. data).Williams (1986) suggested that flying squir-rels were probably present in the San GabrielMountains as well, but there is no documentedevidence to support that contention.

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Chapter 4

Figure 4.28. The distribution of flying squirrels in the San Bernardino Mountains, based primarily on theiroccurrence in spotted owl pellets.

still be widespread in the San BernardinoMountains, but essentially nothing is knownabout their population dynamics or threat fac-tors. Flying squirrels are often observed usingbird feeders around low-density developmentsin heavily forested areas such as organizationalcamps and cabins, but it is unclear if they suc-cessfully inhabit higher-density residentialareas.

An important question is how adept areflying squirrels at dispersing through areas ofunsuitable habitat to maintain populations insuitable, but fragmented, areas. They haveevolved with a naturally fragmented habitatpattern in the San Bernardino Mountains, but

it is unclear what effect, if any, increasing de-velopments on private lands and habitatmodifications on public lands (e.g., ski areadevelopments) are having on the squirrel’s dis-tribution. This species may respond positivelyto increases in white fir density resulting fromrecent fire exclusion, but large stand-replac-ing fires have the potential to dangerouslyreduce suitable habitat and isolate populations.Surveys are needed in the San Jacinto Moun-tains to more conclusively determine its statusthere.

206

Laguna Mountains skipper(Pyrgus ruralis lagunae)

Status and Distribution: The LagunaMountains skipper was federally listed as en-dangered in 1997. This butterfly is knownonly from Laguna and Palomar mountains inSan Diego County (fig. 4.29). On PalomarMountain, it is known to occur in MendenhallValley, lower French Valley, and in the vicin-ity of Observatory Campground. On LagunaMountain, it occurs near the Laguna-El PradoCampground (Levy 1996). Survey informa-tion collected to date indicates that the

San Bernardino white-eared pocket mouse(Perognathus alticolus alticolus)

Status and Distribution: The San Bernar-dino white-eared pocket mouse is a ForestService Region 5 Sensitive Species and a Cali-fornia Species of Special Concern. Knownlocalities of this species are all from the vicin-ity of Strawberry Peak and Little Bear Valleyin the western San Bernardino Mountains atelevations between 5,400 and 5,800 feet (Wil-liams 1986; Best 1994). These are old museumcollections; the white-eared pocket mouse hasnot been collected since 1934 despite exten-sive surveys to relocate it in the late 1970s andearly 1980s (Sulentich 1983; Williams 1986).

Habitat: Little is known, but historicwhite-eared pocket mouse localities were inopen pine forests that contained bracken fern(Best 1994). Williams (1986) suggests thatwhite-eared pocket mice may occur in sage-brush, pinyon-juniper woodlands, and openpine forests on the north side of the San Ber-nardino and possibly the San Gabrielmountains.

Conservation Considerations: Surveys areneeded to determine the current status anddistribution of this species within the assess-ment area. This taxon is endemic to the SanBernardino Mountains, yet there are no re-cent observations of it.

Porcupine (Erethizon dorsatum)Status and Distribution: The porcupine

is a species of local concern because it is rarein southern California and most known loca-tions are within the assessment area. Thedistribution of porcupines in the assessmentarea is somewhat of a mystery. Range maps inZeiner et al. (1990b) suggest they inhabit thenorthern and southern Santa Lucia Ranges,the southern Los Padres ranges, and the SanGabriel and San Bernardino mountains. How-ever, maps in Ingels (1965) and Dodge (1982)suggest they are only in the San Bernardinoand possibly the San Gabriel mountains.

Documented sightings of porcupines inthese mountains are very rare. Vaughan’s(1954) thorough report on mammalian fauna

in the San Gabriel Mountains makes no men-tion of this species. Glenn Stewart (Cal PolyPomona, in litt.) saw a road kill porcupine inthe San Bernardino Mountains in the 1960s.There are also thirdhand reports of a road killbeing found in the San Gabriel Mountains.In 1989, one of the authors (J. Stephenson)observed lodgepole pines stripped of bark, ina fashion that is often indicative of porcupine’spresence (Dodge 1982), in the upper end ofBalky Horse Canyon in the eastern San Ber-nardino Mountains.

Habitat: In California, porcupines are pri-marily found in coniferous forests, but acrosswestern North America they occur in a widevariety of habitats including pinyon-juniperwoodlands, sagebrush, and desert chaparral(Dodge 1982; Zeiner et al. 1990b). Porcupinesfeed extensively on the cambium and foliageof woody shrubs and small trees in winter andon forbs, grasses, and succulent riparian veg-etation in spring and summer (Dodge 1982).

Conservation Considerations: Surveys areneeded to determine the current status anddistribution of this species within the assess-ment area.

Animals of Montane MeadowHabitats

Five animals that are primarily associatedwith montane meadow habitats received in-dividual consideration in this assessment (table4.19). Two of these are butterflies and threeare birds.

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Chapter 4

Table 4.19. Animals associated with montane meadows that received individual consideration.Displayed for each species: (1) the level of knowledge about where it occurs in southern California and, inparentheses, the estimated percentage of locations that are on national forest system lands; (2) the mountainsubareas occupied (y = occurs in breeding season, h = historically occurred, p = potentially occurs, t = transient,w = winter visitor)—if the species is localized and data are available, the approximate number of occurrences may bedisplayed; (3) the vulnerability of populations on national forest system lands to existing threat factors; (4)population trends; and (5) the assigned conservation category.

InvertebratesLaguna Mts. skipper High y High Decl1 Site endangered (40-70%) specificSan Gabriel greenish Mod y High Decl2 Site blue butterfly (> 90%) specific

BirdsCalliope hummingbird Mod p y y y p y p Mod Unkn Landscape

(> 50%) levelMacgillivray’s warbler Low t t p y y t p t p Mod Unkn Landscape

(> 50%) levelLincoln’s sparrow Mod-Low w y y y w y w w Mod Unkn Landscape

(> 50%) level

1 U.S. Fish and Wildlife Service (1997d)2 Murphy (1990)

Montane MeadowAnimals of Concern

federal status

(1)Knowledgeof SoCalLocations

(% on NFs)

(5)Conser-vation

Category

(4) Pop.Trend

(3)Vulner-ability

on NFs

(2) areas occupied or estimated # of occurrences if spp. localized

San Bern. NFCleveland NF Angeles NF Los Padres NFSan

DiegoRngs

SanJacMts

SntaAnaMts

SanBernMts

No.SL

Rng

So.SL

Rng

SanGabMts

Cas-taic

Rngs

So.LP

Rngs

Habitat: The Laguna Mountains skipperis found in montane meadows where its larvalhost plant, Cleveland’s horkelia (Horkeliaclevelandii), occurs. This horkelia, and thebutterfly, are typically found in edaphic or to-pographic situations that provide patches ofbare ground or at least reduced grass cover(e.g., areas with shallow rocky soils or the drierupper margins of meadows). They appear tobe absent from areas that have dense, tall grasscover (Levy 1996). Adult Laguna Mountainsskippers have been frequently observed visit-ing the flowers of a small annual composite,Pentachaeta aurea. This plant may be an im-portant nectar resource (Levy 1996).

population in Mendenhall Valley is substan-tially larger than the others and may supportseveral hundred individuals (Levy 1996; R.Mattoni, in litt., 1998). Laguna Mountain,Observatory Campground, and a portion ofMendenhall Valley are within the ClevelandNational Forest. The occupied portion oflower French Valley is within Palomar Moun-tain State Park.

Conservation Considerations: This but-terfly occurs in very small numbers at only ahandful of sites. There is great concern aboutthe viability of remaining populations andmuch uncertainty over how to manage them.Land use activities occurring in or near areasoccupied by the skipper include cattle grazingand developed recreation sites. Actions are cur-rently being taken by the Cleveland NationalForest to exclude recreational activity in thevicinity of potential skipper habitat. Fenceshave also been erected to exclude grazing insome patches of Cleveland’s horkelia inMendenhall Valley.

The effect of cattle grazing on the hostplant and the butterfly needs further investi-gation. In some respects grazing appears to beclearly detrimental, since cattle have been ob-served foraging on horkelia plants andtrampling flowering stalks. However, onetheory attributes the skipper’s decline to re-ductions in the extent of horkelia (and bareground which may be important for skipperthermoregulation) because of increased grass

208

Figure 4.29. Documented localities for the Laguna Mountains skipper.

cover caused by reduced fire frequencies andthe spread of non-native grasses (Levy 1996).If this is true, grazing may serve an importantfunction as a surrogate for fire—a usefulmechanism to keep grass cover in check. Fur-ther research is needed to clarify this situation.Also, additional surveys are needed, particu-larly on Laguna Mountain, to determine ifadditional skipper populations are present.

San Gabriel Mountains greenish blue(Plejebus saepiolus aureolus)

Status and Distribution: The San GabrielMountains greenish blue butterfly is a formerC2 candidate species. Murphy (1990) statedit was “arguably the prime conservation emer-

gency among the butterfly taxa of California.”It has been collected by several lepidopteristsin a single wet meadow on the Angeles Na-tional Forest in the immediate vicinity of BigPines. It is considered to be a distinctive sub-species, well differentiated from P. s. saepioluswhich occurs in the Sierra Nevada and P. s.hilda which occurs in wet meadows above5,000 feet on Palomar Mountain and in theSan Jacinto and San Bernardino mountains(Murphy 1990). This new greenish blue but-terfly has not recently been observed at themeadow near Big Pines and is feared to beextirpated.

Habitat: The San Gabriel Mountains green-ish blue butterfly is associated with a clover,

209

Chapter 4Trifolium wormskioldii, that grows in moist tomarshy meadow situations (G. Pratt, UC Riv-erside, pers. comm., 1999).

Conservation Considerations: Diversionof water from the meadow at Big Pines, andsubsequent drying of the habitat, has beenimplicated in the possible extirpation of thisundescribed subspecies (Murphy 1990). Sur-veys are needed to determine if the taxon stilloccurs in this meadow or at other potentiallocalities. This situation underscores the im-portance of maintaining adequate surface andground water supplies to meadows and otherwet microhabitats.

Calliope hummingbird (Stellula calliope)Status and Distribution: The calliope

hummingbird is a species of local concernbecause it is a rare breeder in the southernCalifornia mountains. Reported localities onthe Los Padres National Forest include theMount Pinos/Mount Abel area (i.e., aroundIris Meadow, Sheep Camp Meadow, and alongthe McGill trail), Big Pine Mountain(Chokecherry Spring), Frazier Mountain, andReyes Peak (Garrett and Dunn 1981; Lentz1993). Calliope hummingbirds are describedas rare on the north side of the San Gabrieland San Bernardino mountains (Garrett andDunn 1981). In the San Jacinto Mountainsthey are historically known from Round andTahquitz valleys (Grinnell and Swarth 1913).Calliopes also potentially breed on San DiegoCounty’s tallest peak, Hot Springs Mountain(Unitt 1981).

Mist-net and point-count surveys donefrom 1992 to 1996 at Bluff Lake and Metcalfmeadows in the San Bernardino Mountainsfound calliope hummingbirds present in lownumbers at both sites; mist-net results weresimilar at each meadow, with approximatelysix captures per year at Metcalf Meadow andfive per year at Bluff Lake (Rotenberry andCarlson 1997). Another reported locality inthe San Bernardino Mountains is upperArrastre Creek (D. Freeman, unpubl. notes).

Habitat: Calliope hummingbirds breedalong meadow borders and in streamside

thickets (especially willows) within arid mixedconifer forests (Garrett and Dunn 1981).Lentz (1993) found them in association withcurrants (especially Ribes cereum) on MountPinos.

Conservation Considerations: Mainte-nance of riparian vegetation in and aroundmontane meadows is important for this spe-cies. Heavy recreation use, facilitiesdevelopment, and overgrazing by livestock candegrade montane riparian habitat condition.Surface water diversions and/or groundwaterextraction can reduce or eliminate these habi-tats. More information is needed on thecurrent distribution of this species, particu-larly in relation to ongoing land use activitiesin montane riparian and meadow habitats.

MacGillivray’s warbler (Oporornis tolmiei)Status and Distribution: The Mac-

Gillivray’s warbler is a species of local concernbecause it is a rare breeder in the southernCalifornia mountains. It is most common inthe San Gabriel and San Bernardino moun-tains and may only breed in those two ranges(Garrett and Dunn 1981). In the southern LosPadres, Lentz (1993) reports summer obser-vations of MacGillivray’s warbler on Big PineMountain, upper Quatal Canyon, at ThornMeadows near Pine Mountain, and at IrisMeadow on Mount Pinos. However, breed-ing was not confirmed.

Mist-net and point-count surveys donefrom 1992 to 1996 at Bluff Lake and Metcalfmeadows in the San Bernardino Mountainsfound MacGillivray’s warblers present in lownumbers at both sites. Mist-net results indi-cate they were considerably more common atMetcalf Meadow where a high of twenty cap-tures was reached in 1993. The high for BluffLake was five in 1994 (Rotenberry andCarlson 1997).

Habitat: MacGillivray’s warblers occur inwillow thickets and other brushy, montaneriparian areas within coniferous forests above6,000 feet elevation (Garrett and Dunn 1981).

Conservation Considerations: Same asthose described for the Calliope hummingbird.

210

Lincoln’s sparrow (Melospiza lincolnii)Status and Distribution: The Lincoln’s

sparrow is a species of local concern because itis a rare breeder in the southern Californiamountains. Historic nesting localities includeMount Pinos (Iris Meadow), the San GabrielMountains (Big Pines), the San BernardinoMountains (vicinity of Big Bear Lake, GreenValley, and South Fork of the Santa Ana River),and the San Jacinto Mountains (Tahquitz andRound valleys) (Grinnell and Swarth 1913;Garrett and Dunn 1981; Lentz 1993).

Mist-net and point-count surveys done from1992 to 1996 at Bluff Lake and Metcalf mead-ows in the San Bernardino Mountains foundLincoln sparrows to be common at both sites.Twenty to fifty of these sparrows were capturedper year in each meadow during constant-effortmist netting (Rotenberry and Carlson 1997).

Habitat: Lincoln’s sparrows breed in wetmontane meadows; typical vegetation compo-nents include corn lily, sedges, and low willows(Garrett and Dunn 1981).

Conservation Considerations: Same asthose described for the Calliope hummingbird.

Table 4.20. Animals associated with subalpine or alpine habitats that received individualconsideration. Displayed for each species: (1) the level of knowledge about where it occurs in southern Californiaand, in parentheses, the estimated percentage of locations that are on national forest system lands; (2) themountain subareas occupied (y = occurs in breeding season, h = historically occurred, p = potentially occurs,t = transient, w = winter visitor)—if the species is localized and data are available, the approximate number ofoccurrences may be displayed; (3) the vulnerability of populations on national forest system lands to existing threatfactors; (4) population trends; and (5) the assigned conservation category.

Subalpine or AlpineAnimals of Concern

(1)Knowledgeof SoCalLocations

(% on NFs)

(5)Conser-vation

Category

(4) Pop.Trend

(3)Vulner-ability

on NFs

(2) areas occupied or estimated # of occurrences if spp. localized

San Bern. NFCleveland NF Angeles NF Los Padres NFSan

DiegoRngs

SanJacMts

SntaAnaMts

SanBernMts

No.SL

Rng

So.SL

Rng

SanGabMts

Cas-taic

Rngs

So.LP

Rngs

American (water) pipit Low t t p y p t t t t Mod Unkn Site(100%) specific

Lodgepole chipmunk Mod y y y y* Low Unkn Landscape(> 70%) level

* A distinct subspecies, the Mount Pinos lodgepole chipmunk occurs in the southern Los Padres ranges.

American (water) pipit (Anthus spinoletta)Status and Distribution: The American

water pipit is a local species of concern be-cause it breeds in alpine habitats and is knownfrom only one location in the southern Cali-fornia mountains. A pair of water pipits waspresent, and probably nested, on Mount SanGorgonio in the summer of 1978 (Garrett andDunn 1981).

Habitat: Water pipits nest above timber-line. They commonly winter in the vicinity ofagricultural fields (Garrett and Dunn 1981).

Conservation Considerations: Surveys areneeded to determine if water pipits breed regu-larly on Mount San Gorgonio or if breedingis a rare, irregular occurrence. Potential breed-ing habitat on Mount San Gorgonio and thehighest portions of the San Gabriel Mountainsshould also be surveyed. All of these areas arewithin designated wilderness areas, but recre-ation activity near mountain summits couldpotentially impact this species.

Lodgepole chipmunk (Tamias speciosus)Status and Distribution: Two subspecies

of lodgepole chipmunk occur in the assess-ment area. The Mount Pinos lodgepolechipmunk, T. s. callipeplus, occurs only in theforests around Mount Pinos and Mount Abel(Williams 1986). It is a Forest Service Region

Animals of Subalpine or AlpineHabitats

Two animal species that are primarily as-sociated with subalpine or alpine habitats wereconsidered individually in this assessment(table 4.20).

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Chapter 45 Sensitive Species. Lodgepole chipmunks inthe San Gabriel, San Bernardino, and SanJacinto mountains belong to the subspecies T.s. speciosus (Best et al. 1994). The elevationrange of this species is from just above 6,000feet to over 10,000 feet (Williams 1986;Zeiner et al. 1990b).

Habitat: Lodgepole chipmunks are gen-erally found in open-canopy forests with a mixof shrubs and trees. They are common inlodgepole pine forests but also occur in open-canopy stages of other forest habitats includingwhite fir, Jeffrey pine, and mixed conifer. Theyappear to avoid pure stands of conifers, pre-ferring an understory shrub component,particularly chinquapin or manzanita(Vaughan 1954; Williams 1986; Zeiner et al.1990b).

Conservation Considerations: The lodge-pole chipmunk’s high elevation habitats do notappear to be highly vulnerable to existing landuse activities or agents of change. However,habitat for the Mount Pinos subspecies is ex-tremely limited, which increases the impactof even small losses of suitable habitat in theMount Pinos/Mount Abel area. A single, largestand-replacing fire could eliminate this sub-species.

Animals of Desert MontaneHabitats

Sixteen animal species that are prima-rily associated with desert montane habitatswere considered individually in this assess-ment (table 4.21). There are sixinvertebrates, one reptile, seven birds, andtwo mammals.

Desert Montane InvertebratesDesert monkey grasshopper(Psychomastix pysylla deserticola)

Status and Distribution: The desert mon-key grasshopper is a former C2 candidate forfederal listing. It is endemic to lower desert-side slopes of the San Bernardino Mountains(J. Powell, UC Berkeley Department of En-tomology, pers. comm.).

Habitat: Little information is available. Itis described as occurring in arid environments,and chamise is identified as a possible foodplant.

Conservation Considerations: No threatshave been identified for this species. More in-formation is needed on its distribution andhabitat requirements on the desert side of theSan Bernardino Mountains.

San Bernardino Mountains silk moth(Coloradia velda)

Status and Distribution: The silk mothColoradia velda is a species of local concernbecause it is endemic to the San BernardinoMountains. The type locality for this speciesis at Coxey Meadow on the north side of theSan Bernardino Mountains, and it has alsobeen collected at Horse Springs, Crab Flat,Cactus Flat and Barton Flats (Johnson andWalter 1979).

Habitat: Coloradia velda is most com-monly found in stands of pinyon pine, whichis suspected to be the larval host plant(Johnson and Walter 1979).

Conservation Considerations: More in-formation is needed on the distribution andhabitat requirements of this silk moth. Nothreat factors have currently been identifiedfor it.

Bright blue copper(Lycaena heteronea clara)

Status and Distribution: The bright bluecopper butterfly is a local species of concern.Murphy (1990) considered it to be a categoryB taxon, which he defined as one that war-rants listing as endangered, but with a lesspressing need than category A taxa. This but-terfly historically occurred in isolated areas ofthe Piute and Tehachapi mountains, in theCastac Valley (near Fort Tejon), and nearSilverwood Lake in the San Bernardino Moun-tains (Orzak 1976). However, as of 1976, it isknown only from Cuddy and Lockwood val-leys near Frazier Park (Murphy 1990). Orzak(1976) estimated that as many as thirty popu-lations existed in this area, with the highest

Desert MontaneAnimals of Concern

federal status

(1)Knowledgeof SoCalLocations

(% on NFs)

(5)Conser-vation

Category

(4) Pop.Trend

(3)Vulner-ability

on NFs

(2) areas occupied or estimated # of occurrences if spp. localized

San Bern. NFCleveland NF Angeles NF Los Padres NFSan

DiegoRngs

SanJacMts

SntaAnaMts

SanBernMts

No.SL

Rng

So.SL

Rng

SanGabMts

Cas-taic

Rngs

So.LP

Rngs

Table 4.21. Animals associated with desert montane habitats that received individual consideration.Displayed for each species: (1) the level of knowledge about where it occurs in southern California and, inparentheses, the estimated percentage of locations that are on national forest system lands; (2) the mountainsubareas occupied (y = occurs in breeding season, h = historically occurred, p = potentially occurs, t = transient,w = winter visitor)—if the species is localized and data are available, the approximate number of occurrences may bedisplayed; (3) the vulnerability of populations on national forest system lands to existing threat factors; (4)population trends; and (5) the assigned conservation category.

Invertebrates

Desert monkey Low y Unkn Unkn Landscape grasshopper (30-70%) levelSan Bernardino Mts. Mod y Unkn Unkn Landscape silk moth (> 70%) level

Bright blue copper Mod h/p p y High Unkn Site butterfly (10-50%) specific

San Emigdio blue Low y y y Unkn Unkn Site butterfly (10-40%) specific

Dammer’s blue butterfly Mod y Unkn Unkn Landscape(> 70%) level

Vernal blue butterfly Mod y Unkn Unkn Landscape(> 90%) level

Reptiles

Small-scaled lizard Mod y Low Unkn Landscape(< 20%) level

Birds

Zone-tailed hawk Mod y y Low Unkn Landscape(40-60%) level

Common nighthawk Mod p y y Mod Unkn Site(40-70%) specific

Gray flycatcher Low p y y Low Unkn Landscape(> 50%) level

Pinyon jay Mod y y p Mod Unkn Landscape(< 20%) level

Gray vireo Mod y y y y Mod Decl1 Landscape(40-80%) level

Plumbeus solitary vireo Low y y Low Unkn Landscape(> 50%) level

Hepatic tanager Mod t y t t Low Unkn Landscape(> 60%) level

Mammals

Tehachapi pocket mouse Mod p h/p y Unkn Unkn Landscape(> 60%) level

Peninsular Ranges’ High y High Decl2 Site bighorn sheep (< 5%) specific endangered

1 Garrett and Dunn (1981)2 USDI Bureau of Land Management et al. (1996)

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Chapter 4concentration in Cuddy Valley, 2 to 5 mileswest of Interstate 5.

Habitat: In the arid montane valleysaround Cuddy Valley and Frazier Park, thebright blue copper occurs in sagebrush-domi-nated shrublands. Three different buckwheat(Eriogonum) species are known larval foodplants: E. heermannii, E. umbellatum munzii,and E. fasciculatum polifolium (Orzak 1976).

Conservation Considerations: Most ofthe valley bottomland in Cuddy andLockwood valleys is private land and a lot ofdevelopment is occurring in this area. Thereis some potential habitat for this butterfly onthe Los Padres National Forest. Surveys areurgently needed to see if populations of thebright blue copper occur on national forestsystem lands in this area. Any discovered popu-lations should receive site-specificmanagement attention until the status of thistaxon is better determined.

San Emigdio blue butterfly(Plebulina emigdionis)

Status and Distribution: The SanEmigdio blue butterfly is a former Category 2Candidate Species. Murphy (1990) considersit to be a category B taxon, which he definedas one that warrants listing as endangered, butwith a less pressing need than category A taxa.The primary location where this species hasbeen collected is along the Mojave River nearVictorville, but isolated colonies within or nearthe assessment area are reported from Bou-quet and Mint canyons near Castaic, incanyons along the north side of the SanGabriel Mountains near the desert’s edge, andin arid areas south of Mount Abel near SanEmigdio Mesa (Emmel and Emmel 1973;Murphy 1990).

Habitat: The San Emigdio blue is closelyassociated with the widespread saltbush,Atriplex canescens, in alkali sink areas (Murphy1990). However, the butterfly’s distributionis much more localized than the host plant,suggesting that other factors may determinehabitat suitability. Murphy (1990) speculatesthat there may be an obligatory mutualistic

relationship between this species and one ormore ant species.

Conservation Considerations: Additionalinformation is needed on the distribution andstatus of this butterfly on public lands in theassessment area. At a minimum, the knownlocalities mentioned above need to be revistedto see if populations still exist. The best-knownpopuluation near Victorville has declined dueto urbanization (Murphy 1990).

Dammer’s blue butterfly(Euphilotes enoptes dammersi)

Status and Distribution: This subspeciesis newly described and known only fromBaldwin Lake, Arrastre Flat, and ArrastreCreek in the San Bernardino Mountains (Prattand Emmel 1998).

Habitat: At Baldwin Lake and ArrastreFlat, this butterfly is closely associated withspring-blooming populations of the wildbuckwheat Eriogonum kennedyi, which com-monly grows on pebble plains. On dry slopesnear Arrastre Creek, a slightly different formof this subspecies is associated with spring-blooming populations of Eriogonum davidsonii(Pratt and Emmel 1998).

Conservation Considerations: Too littleis currently known about this taxon to assessits conservation status. Gordon Pratt at UCRiverside is the authority on this butterfly.

Vernal blue butterly(Euphilotes baueri [battoides] vernalis)

Status and Distribution: This newly de-scribed subspecies has only been found atCoxey Meadow (elevation 5,600 feet) on thenorth side of the San Bernardino Mountains(Pratt and Emmel 1998). It also occurs far tothe north of the assessment area in the CosoMountains near China Lake.

Habitat: The vernal blue butterfly is asso-ciated with spring-blooming populations ofthe wild buckwheat, Eriogonum kennedyi. Thisassociation is similar to that of the Dammer’sblue, but it occurs in different areas and is dis-tinctly different taxonomically (Pratt andEmmel 1998).

214

Conservation Considerations: More in-formation is needed on the distribution andhabitat requirements of this species within theassessment area. As yet, no threat factors havebeen identified for this taxon.

Desert Montane Reptiles

Small-scaled lizard(Urosaurus microscutatus)

Status and Distribution: The small-scaledlizard is a local species of concern because itsrange in the United States is restricted to therocky mountains and foothills of eastern SanDiego County (Zeiner et al. 1988). Knownlocalities in or near the assessment area includecanyons in Anza-Borrego Desert State Parkthat come off the east sides of Bucksnort, HotSprings and San Ysidro mountains (i.e., AlderCanyon, South Fork of Sheep Canyon,Borrego Palm Canyon, and Hellhole Canyon),and far to the south at Jacumba, Barrett Junc-tion, and near Barrett Dam along the DulzuraConduit (J. Copp, CA Academy of Sciences,pers. comm.).

Habitat: The small-scaled lizard inhabitsarid and semiarid environments in areas wherethere are rock outcrops or rocky canyons(Zeiner et al. 1988). It is most common indesert-side habitats, particularly desert can-yons, but also occurs on coastal slopes insouthern San Diego County in chaparral andother habitats (J. Copp, pers. comm.).

Conservation Considerations: Surveys areneeded to better determine the distributionand abundance of this species on public landswithin the assessment area. However, thesmall-scaled lizard’s habitat requirements arenot likely to make it particularly vulnerableto land use activities occurring on nationalforest system lands.

Desert Montane BirdsZone-tailed hawk (Buteo albonotatus)

Status and Distribution: The zone-tailedhawk is a local species of concern because it isa rare breeder in southern California and thefew known nesting localities are within theassessment area. Zone-tailed hawk nests have

been documented on Hot Springs Mountain(San Diego County) in 1993 (SDNHM 1998)and on Santa Rosa Mountain (RiversideCounty) in 1980 (Garrett and Dunn 1981;McCaskie 1982). These locations are the ex-treme western extent of this species’ breedingrange.

Habitat: Zone-tailed hawks commonlyinhabit desert mountains, particularly innorthern and central Arizona.

Conservation Considerations: Additionalsurvey work is needed to determine if zone-tailed hawks breed regularly in either the SantaRosa Mountains or the eastern mountains ofSan Diego County. However, we believe theirvulnerability to existing land use activities is low.

Common nighthawk (Chordeiles minor)Status and Distribution: The common

nighthawk is a local species of concern becauseit is a rare breeder in southern California andthe few known nesting localities are within theassessment area. This species is found only inthe eastern San Bernardino Mountains (par-ticularly near Baldwin Lake) and on TableMountain near Wrightwood in the SanGabriel Mountains (Garrett and Dunn 1981;D. Cooper, UC Riverside, in litt.).

Habitat: Common nighthawks forageover a variety of habitats from open conifer-ous forest to sagebrush plains and arefrequently seen foraging over open bodies ofwater. Some open, gravelly substrate is re-quired for nesting (Garrett and Dunn 1981).

Conservation Considerations: Surveys areneeded to identify the specific areas where thishighly localized species nests. Both of the lo-cations where common nighthawks occur areareas that receive a high level of recreation use.More survey work is needed to determine ifland use activities in these areas are affectingnighthawk nesting grounds.

Gray flycatcher (Empidonax wrightii)Status and Distribution: The gray fly-

catcher is a local species of concern because itis a rare breeder in southern California andthe few known nesting localities are within theassessment area. This species is found only in

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Chapter 4

Habitat: In the San Jacinto Mountainsand San Diego ranges, gray vireos are typi-cally found in stands of dense, maturechaparral that are dominated by chamise orredshank (Unitt 1984). In the San Gabriel andSan Bernardino mountains they are found onbrushy slopes in pinyon-juniper woodlands(Garrett and Dunn 1981). However, grayvireos are highly localized in these plant asso-ciations, suggesting that other habitatrequirements may be influencing their distri-bution.

Conservation Considerations: Surveywork is needed to better document the distri-bution and abundance of gray vireos in theassessment area. Systematic surveys resultingfrom the development of breeding bird atlasesin Los Angeles (LACBBA 1999) and San Di-ego (SDNHM 1999) counties should help inthis regard. Like most vireos, gray vireos areconsidered highly susceptible to cowbird nestparasitism and this has been implicated as apossible reason for their decline (Unitt 1984).Cowbird parasitism of gray vireo nests has

northern portions of the San Gabriel and SanBernardino mountains (Garrett and Dunn1981). This species was not detected in sur-veys conducted in the early 1900s and mayhave expanded its breeding range into the as-sessment area in just the last fifty years(Johnson and Garrett 1974). Documentedlocalities include Sheep Creek nearWrightwood and areas east of Baldwin Lake,including Arrastre Creek (Johnson and Garrett1974).

Habitat: Gray flycatchers are closely tiedto pinyon-juniper-sagebrush associations butdo breed locally in other arid conifer associa-tions (Garrett and Dunn 1981).

Conservation Considerations: More in-formation is needed on the distribution andstatus of gray flycatchers in the assessment area.However, we believe their vulnerability to ex-isting land use activities is low.

Pinyon jay (Gymnorhinus cyanocephalus)Status and Distribution: The pinyon jay

is a local species of concern because it is a rareand localized breeder in the assessment area.Known localities include the northeastern SanBernardino Mountains, particularly aroundBaldwin Lake, and Garner Valley in the SanJacinto Mountains (Garrett and Dunn 1981).Small groups have been seen around MountPinos but generally only in the fall and winter(Garrett and Dunn 1981). Lentz (1993) doesnot mention pinyon jays in her review of birdsin the southern Los Padres mountain ranges.

Habitat: Pinyon jays occupy mature pin-yon-juniper-yucca woodland on aridmountain slopes and open montane valleysof sagebrush and grassland with are borderedby pinyons, western junipers, or Jeffrey pines(Garrett and Dunn 1981).

Conservation Considerations: Same asthose described for the gray flycatcher. How-ever, the pinyon jay may be negativelyaffected by the steady increase in housingdevelopments on private lands in somemontane valleys (e.g., Baldwin Lake andGarner Valley).

Gray vireo (Vireo vicinior)

Status and Distribution: The gray vireois a California Species of Special Concern. Itis a summer resident in a few highly localizedareas within the assessment area (fig 4.30). Itoccurs on dry desert-facing slopes in the SanGabriel Mountains (e.g., near Valyermo), SanBernardino Mountains (e.g., Rose Mine andCactus Flats), and San Jacinto Mountains (e.g.,Pinyon Flats) (Garrett and Dunn 1981; D.Cooper, UC Riverside, in litt.). In San DiegoCounty, gray vireos occur in arid shrublandsnorth of Warner Springs between Palomar andHot Springs mountains, and on the southernflank of the Laguna Mountains from PineValley Creek southeast to La Posta Creek(Unitt 1984; SDNHM 1998).

Early work by Grinnell and associates in-dicates that the gray vireo used to be morewidespread, particularly in the San Gabriel andSan Jacinto mountains (Grinnell and Swarth1913; Grinnell and Miller 1944). Little isknown about the extent or cause of its declinein these areas.

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been documented in the San BernardinoMountains (Hanna 1944).

Plumbeus solitary vireo(Vireo solitarius plumbeus)

Status and Distribution: The rarity of thisdistinctive subspecies in southern Californiaand its restriction to arid montane habitats arewhy the Plumbeus solitary vireo was identi-fied as a local species of concern. It has beenobserved in Big Rock Creek Canyon on thenorth side of the San Gabriel Mountains andin upper Arrastre Creek on the north side ofthe San Bernardino Mountains (Garrett andDunn 1981). This subspecies was not recordedin California prior to 1962 and appears to have

undergone a major westward expansion of itsrange in the mid-1900s (Johnson and Garrett1974).

Habitat: Plumbeus solitary vireos breedin arid woodlands of mature pinyon pine,white fir, and Jeffrey pine, often extending intoadjacent riparian growth (Garrett and Dunn1981).

Conservation Considerations: More in-formation is needed on the distribution andabundance of this subspecies in the assessmentarea. However, we believe its vulnerability toexisting land use activities is low.

Figure 4.30. Known locations of the gray vireo in the assessment area.

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Chapter 4Hepatic tanager (Piranga falva)

Status and Distribution: The rarity of thisdistinctive species in southern California andits restriction to arid montane habitats are whythe hepatic tanager was identified as a localspecies of concern. It is known to occur onlyin the San Bernardino Mountains; docu-mented localities include upper Arrastre Creekand Round Valley, both east of Baldwin Lake(Johnson and Garrett 1974; Garrett and Dunn1981).

Habitat: Breeding habitat for hepatic tana-gers in the San Bernardino Mountains consistsof mature pinyon pine woodland with a mix-ture of taller conifers, such as white fir orJeffrey pine (Garrett and Dunn 1981).Johnson and Garrett (1974) suggest thesetanagers also may occur in pine and decidu-ous oak woodlands on warm, arid slopes.

Conservation Considerations: Additionalinformation is needed on the distribution andabundance of this species in the assessmentarea. It could also occur in the San Gabrieland San Jacinto mountains. The mature wood-land habitats occupied by hepatic tanagers areat some risk to loss in stand-replacing fires butotherwise are not particularly vulnerable toexisting land use activities.

Desert Montane MammalsTehachapi white-eared pocket mouse(Perognathus alticola inexpectatus)

Status and Distribution: The Tehachapipocket mouse is a Forest Service Region 5 Sen-sitive Species and a California Species ofSpecial Concern. This taxon is endemic to theTehachapi Mountains and the western Trans-verse Ranges (Best 1994). Known localitieswithin the assessment area, based on museumrecords and historic information, are near LakeHughes, Elizabeth Lake, and Quail Lake onthe desert side of the Castaic Ranges, and atPinyon Pines, Cuddy Valley, and ChuchupateCampground in the Mount Pinos/FrazierMountain region (Williams 1986; Best 1994;CNDDB 1999). The only one of these loca-tions where Techachapi pocket mice have beenrecently observed is at Chuchupate Camp-ground, where they were found in 1998 by

public health biologists monitoring vector-borne diseases (R. Davis, CA Department ofHealth Services, pers. comm. to M. Foster,1998).

Habitat: Habitat associations of theTehachapi pocket mouse are not well defined.They have been collected in arid annual grass-land, desert scrub communities, pinyon pinewoodland, a grain field, and in open desert-side pine forest at elevations between 3,500and 6,000 feet (Williams 1986).

Conservation Considerations: So little isknown about the status of the Tehachapipocket mouse that it would be shear specula-tion to suggest threat factors and conservationneeds. Surveys are needed to determine thedistribution and relative abundance of thisspecies on public lands within the assessmentarea. Williams (1986) identifies desert-facingslopes of the San Gabriel Mountains, theCastaic Ranges, and the Mount Pinos/FrazierMountain region as areas where this mousemay be found.

Peninsular Ranges’ bighorn sheep(Ovis canadensis “cremnobates”)

Status and Distribution: Bighorn sheep(fig. 4.31) populations in the PeninsularRanges of southern California were federallylisted as endangered in 1998. There is uncer-tainty over whether these populationsrepresent a taxonomically distinct subspeciesor simply a discrete metapopulation(Wehausen and Ramey 1993; USFWS1998f ). Peninsular Ranges’ bighorn sheep oc-cur from the eastern flanks of the San Jacintoand Santa Rosa mountains southeast into thedesert ranges of Anza-Borrego State Park tothe Mexican border (fig. 4.32) (Rubin et al.1998).

The Peninsular Ranges’ metapopulationis composed of eight distinct populations(Boyce 1995). Four of these populations liepartially within the assessment area; the restare in desert ranges to the east. There are anestimated 25 sheep in the San Jacinto Moun-tains, and 117 sheep in three recognizedpopulations within the Santa Rosa Mountains

218

Based on discussions with people who haveknowledge of these species’ distributions, itappears that none of the six have significantpopulations on public lands within the assess-ment area. Thus, we consider all of them tobe species whose conservation can be mini-mally influenced by management of publiclands in this area.

in some areas by mountain lions and possiblycoyotes (USDI BLM et. al. 1996).

Specific management actions for conserv-ing Peninsular Ranges’ bighorn sheep and theirhabitats have been developed by an inter-agency coordinating committee. Thisdirection is in the process of being adopted byall state and federal land and resource man-agement agencies in the affected region (USDIBLM et. al. 1996).

Animals of Desert Floor HabitatsSix potentially vulnerable animals are

desert species whose distributions may extendinto the assessment area along its extremenorthern and eastern boundaries (table 4.22).Although we knew from the start that the as-sessment area contains little suitable habitatfor these species, it was still important to evalu-ate their conservation potential andvulnerability. One important reason for do-ing this is to clearly document that public landsin the assessment area will not be sufficient toconserve these species.

(USDI BLM et. al. 1996). However, only anestimated 2 percent of Peninsular Ranges’ big-horn sheep habitat occurs on the SanBernardino National Forest; BLM (29 per-cent) and state park (41 percent) lands makeup most of the sheep’s range, and some criti-cal lambing habitat also occurs on private lands(USDI BLM et. al. 1996). Studies have docu-mented declines in most of the PeninsularRanges’ populations (USDI BLM et. al. 1996).

Habitat: Bighorn sheep habitat in the Pen-insular Ranges is characterized by steep slopes,canyons, and washes. Although they can oc-cur at high elevations, these sheep typicallyare found at elevations below 4,600 feet, whichin this area is below the pinyon-juniper wood-lands (Rubin et al. 1998). Topography in apatchwork of varying slopes is important forbighorn sheep. Steep (50 to over 70 percentslope) and rough (i.e., with a lot of small-scalechanges in slope) terrain is utilized extensivelyfor escape cover, but flatter areas at the base ofthe mountains are often used for foraging(USDI BLM et. al. 1996).

Conservation Considerations: The pri-mary factors believed to be affecting PeninsularRanges’ bighorn sheep are (1) habitat loss orabandonment due to encroaching human de-velopment along the base of the mountainsand extending up into them; (2) diseases thatcan be transmitted by domestic livestock, par-ticularly sheep; and (3) high levels of predation

Desert tortoise(Xerobates [Gopherus] agassizii)

Status and Distribution: The desert tor-toise is state and federally listed as endangered.Surveys for the desert tortoise have been fairlywidespread and it has been documented closeto the assessment area (fig. 4.33)(CNDDB1999). However, suitable habitat for this spe-cies disappears rapidly as you move up intothe mountains. It is possible that tortoises oc-cur in small numbers along the northern baseof the San Bernardino Mountains, where thereis friable soil and relatively flat terrain.

Habitat: Desert tortoises occur in a widevariety of desert habitats, including washes andJoshua tree woodlands. They reach highest

Figure 4.31. Peninsular Ranges’ bighorn sheep areoften found in steep, rocky terrain above the desertfloor. USFWS FILE PHOTO

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Chapter 4

Bendire’s thrasher (Toxostoma bendirei)Status and Distribution: The Bendire’s

thrasher is a California Species of Special Con-cern and is identified as an “extremely high

densities in creosote bush communities withextensive annual wildflower blooms, such asoccur in the western Mojave Desert (Zeineret al. 1988). They require friable soil for bur-row construction.

Conservation Considerations: It appearsunlikely that desert tortoises occur within theassessment area in any significant numbers.Thus, management of public lands within theassessment area will have little influence onthe conservation of this species.

priority” watch list species by Partners in Flight(Carter et al. 1998). There are several reportedlocations of Bendire’s thrasher in Joshua treewoodlands along the northern and eastern baseof the San Bernardino Mountains, includingLucerne Valley and Pioneertown (England andLaudenslayer 1989).

Habitat: At almost all sites where Bendire’sthrashers nest in California the most promi-nent plants are Joshua tree, Spanish bayonet(Yucca baccata), or Mojave yucca (Yuccaschidigera). They seem to avoid steep slopesand rocky terrain (England and Laudenslayer1989).

Conservation Considerations: Protectionof Joshua tree woodlands is important for this

Figure 4.32. Distribution of the Peninsular Ranges’ bighorn sheep.

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species. More information is needed on thedistribution and abundance of Bendire’sthrashers on public lands in the San Bernar-dino Mountains. However, the assessment areais on the extreme edge of this species’ range withonly a small amount of potential habitat.

Le Conte’s thrasher (Toxostoma lecontei)Status and Distribution: The Le Conte’s

thrasher is a California Species of Special Con-cern and is identified as an “extremely highpriority” watch list species by Partners in Flight(Carter et al. 1998). LeConte’s thrashers areknown to occur in Joshua tree woodlands inthe Mojave Desert and arid desert scrub inthe Carrizo Plain (Garrett and Dunn 1981),but we found no documented localities withinthe assessment area.

Habitat: Le Conte’s thrashers require lessvegetation than other thrashers; they inhabitvery sparse desert scrub (e.g., creosote bush),especially around small washes. They also oc-

cupy Joshua tree woodlands in the MojaveDesert, although the Joshua trees themselvesseem an unimportant element. In the south-western San Joaquin Valley, stands of saltbushare occupied and nesting usually takes placearound the edges of washes (Garrett and Dunn1981).

Conservation Considerations: It appearsunlikely that Le Conte’s thrashers currentlyoccur within the assessment area. Thus, man-agement of public lands within the assessmentarea will not influence the conservation of thisspecies.

Summer tanager (Piranga rubra)Status and Distribution: The summer

tanager is a California Species of Special Con-cern. There is recent (1998) documentationof summer tanagers nesting along the SantaClara River in Soledad Canyon and along BigRock Creek near the town of Valyermo (D.Cooper, UC Riverside, in litt.), although nei-ther location appears to be on public land. Dan

Birds

Bendire’s thrasher Mod y Low Unkn Minimal(< 1%) Influence

Le Conte’s thrasher Mod p p p p Low Unkn Minimal(< 1%) Influence

Summer tanager Mod t t t y Low Unkn Minimal(< 5%) Influence

Mammals

California leaf-nosed Low y p p p p p Unkn Unkn Minimal bat (< 5%) Influence

Mohave ground squirrel Low p p Low Unkn Minimal (0%) Influence

Desert FloorAnimals of Concern

federal status

(1)Knowledgeof SoCalLocations

(% on NFs)

(5)Conser-vation

Category

(4) Pop.Trend

(3)Vulner-ability

on NFs

(2) areas occupied or estimated # of occurrences if spp. localized

San Bern. NFCleveland NF Angeles NF Los Padres NFSan

DiegoRngs

SanJacMts

SntaAnaMts

SanBernMts

No.SL

Rng

So.SL

Rng

SanGabMts

Cas-taic

Rngs

So.LP

Rngs

Table 4.22. Animals associated with desert habitats that received individual consideration.Displayed for each species: (1) the level of knowledge about where it occurs in southern California and, inparentheses, the estimated percentage of locations that are on national forest system lands; (2) the mountainsubareas occupied (y = occurs in breeding season, h = historically occurred, p = potentially occurs, t transient,w = winter visitor)—if the species is localized and data are available, the approximate number of occurrences may bedisplayed; (3) the vulnerability of populations on national forest system lands to existing threat factors; (4)population trends; and (5) the assigned conservation category.

Reptiles

Desert tortoise Mod p p Low Unkn Minimal threatened (< 1%) Influence

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Chapter 4

Figure 4.33. Range of the desert tortoise and known locations of the tortoise and Mohave ground squirrel inthe vicinity of the assessment area (from CNDDB 1999).

Cooper stated that they probably nest in Fre-mont cottonwood groves all along thenorthern base of the San Gabriel Mountains.Summer tanagers are also reported from theMojave River at Mojave Narrows RegionalPark and Whitewater Canyon along the baseof the San Bernardino Mountains (P. Unitt,SDNHM, unpubl. document), and the lowerreaches of Palm and Andreas canyons on thedesert-side of the San Jacinto Mountains (D.Freeman, San Bernardino NF, unpubl. notes).

Habitat: Summer tanagers nest in desertriparian groves, typically dominated by ma-ture Fremont cottonwoods (Garrett and Dunn1981).

Conservation Considerations: Ripariangallery forests on the desert’s edge at the baseof the San Gabriel, San Bernardino, and SanJacinto mountains are important habitats forsummer tanagers and should be protected.There is a need to document where these habi-tats occur on public lands and survey thoseareas for summer tanagers.

California leaf-nosed bat(Macrotus californicus)

Status and Distribution: The Californialeaf-nosed bat is a California Species of Spe-cial Concern. The distribution of this speciesin the assessment area is poorly known; it was

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not detected in bat surveys conducted by theForest Service from 1996 to 1998 (Simons etal. in prep.). California leaf-nosed bats havereportedly been observed in the Arrastre Creekarea of the San Bernardino Mountains and onthe desert side of the San Jacinto Mountains(Diane Freeman, San Bernardino NF, unpubl.notes).

Habitat: California leaf-nosed bats arestrongly associated with desert riparian andwash habitat. Radio-telemetry work done onthis species in the California desert found themforaging almost exclusively in desert washes(Brown et al. 1993). They roost in mine shaftsand caves (Brown 1998). Long, warm minetunnels are utilized for winter roosts and ma-ternity colonies (Berry and Brown 1995).

Conservation Considerations: Desert ri-parian habitats and suitable mine shafts areimportant to the conservation of this species.Surveys are needed to determine if occupiedroosting or foraging habitat occurs within theassessment area.

Mohave ground squirrel(Spermophilus mohavensis)

Status and Distribution: The Mohaveground squirrel is state listed as threatened.The current range of this species, delineated,is well north of the San Gabriel and San Ber-nardino mountains in the Mojave Desert (Best1995). However, there are historic recordsfrom Apple Valley and Lucerne Valley (fig.4.33) (Whitaker 1991). These are close to theSan Bernardino Mountains and potential habi-tat seems to extend a short ways up into themountains. Mohave ground squirrels havebeen found at elevations up to 5,000 feet insome desert ranges (Best 1995).

Habitat: Optimal habitats for Mohaveground squirrels are open desert scrub (e.g.,creosote bush), open alkali scrub (e.g., salt-bush), and Joshua tree woodlands (Zeiner etal. 1990b). They typically construct burrowsin the sandy soils of desert washes (Best 1995).

Conservation Considerations: It appearsunlikely that Mohave ground squirrels cur-rently occur within the assessment area. Thus,

management of public lands within the assess-ment area will not influence the conservationof this species.