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Bird Monitoring of the Bureau of Land Management Bishop Resource Area
Aspen Stewardship Project
Results of the 2008 field season with comparisons to 2004, 2005, 2006 and 2007.
White-crowned Sparrow Fledgling (photo C. Woolley)
Stella S. Moss February 2009
PRBO Conservation Science
3820 Cypress Dr. #11 Petaluma, CA 94954
707-781-2555 www.prbo.org
PRBO Contribution # 1669
TABLE OF CONTENTS
EXECUTIVE SUMMARY …………………………………………………………………………… 1
BACKGROUND AND INTRODUCTION …………………………………………………………… 2
STUDY AREA AND METHODS …………………………………………………………………… 4
RESULTS ………………………………………………………………………………………… 9
ACKNOWLEDGEMENTS …………………………………………………………………………… 21
LITERATURE CITED …………………………………………………………………………......... 21
APPENDIX …………….………………………………………………………………………….. 24
LIST OF TABLES
Table 1. Area Search plot information …………………………………………………………… 5
Table 2. Area Search census dates …………...………………...……...………...……...………... 6
Table 3. Breeding status for all bird species at Virginia Creek lodgepole pine thinning treatment sites …….………...……... 9
Table 4. Total number of detections, species richness and diversity for Virginia Creek lodgepole pine thinning treatment sites …..……………….. 11
Table 5. All nests found at Virginia Creek lodgepole pine thinning treatment sites ……………….. 12
Table 6. Breeding status for all bird species at Virginia Creek burn sites ...……………….……….... 14
Table 7. Total number of detections, species richness and diversity at Virginia Creek Burn sites .…... 16
Table 8. All nests found at Virginia Creek Burn sites ……………………………………………... 17
Table 9. Breeding status for all species at Bodie Hills Livestock Exclusion sites …………………… 18
Table 10. Total number of detections, species richness and diversity at Bodie Hills Livestock Exclusion sites ……………… 19
Table 11. All nests found at Bodie Hills Livestock Exclusion sites …..……………….………....… 20
LIST OF FIGURES
Figure 1. General locations of plots within study area at Virginia Creek and Bodie Hills …………… 4Figure 2. Nest substrate for Virginia Creek lodgepole pine thinning treatment sites ……………….. 13
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EXECUTIVE SUMMARY In an effort to improve quaking aspen (Populus tremuloides) regeneration, the Bureau of Land Management Bishop Field Office is testing three different management techniques typically used to regenerate aspen groves: cutting of lodgepole pines (Pinus contorta), prescribed burning and exclusion of livestock from groves. In coordination with this effort, BLM and PRBO Conservation Science (PRBO) have collaborated to implement a bird monitoring program to coincide with the active management of these sites. Lodgepole Pine Thinning At three sites along Virginia Creek, Mono County, California lodgepole pines were removed in the fall of 2004, 2005 and 2006. We documented 55 species at treatment sites (coded TR) and control sites (coded CO) from 2004 ‐2008 and determined breeding status for each. New confirmed breeders in 2008 were Dusky Flycatcher, Mountain Bluebird and Yellow Warbler. In general species richness, diversity and total detections have increased in the first three years after treatment at TRV1 and TRV2 but slightly decreased in the fourth year (2008) after treatment. Overall, bird numbers at TRV1 were similar to those on its control plot. TRV2 total detections and species richness have been consistent since treatment, whereas COV2 total detections decreased significantly as well as species richness. TRV3 and COV3 had the only increase in total detections, species richness and species diversity. We found a total of 23 nests in 2008. Prescribed Burn We documented 40 species at the Virginia Creek burn study sites in 2007 and 2008 (all treatment sites, no control plot) and determined breeding status for each. We detected 10 new species in 2008. The only new confirmed breeder is the Cassin’s Finch. TDOG and TDOG2 both had a decrease in total detections post‐treatment. Species richness decreased significantly on TDOG2 post‐treatment. VIBU1 had a slight increase in total detections, species richness and diversity. Total detections on VIBU2 on the other hand more than doubled and species richness and diversity also came close to being twice as high in the post‐treatment year. We found a total of 11 nests. Livestock Exclusion We documented 32 species at these sites in 2007 and 2008 and determined breeding status for each. We found 19 nests for five species. Livestock were excluded from one site (NOPP3) prior to monitoring in 2008; all other monitoring was pre‐treatment. SFACT had the highest species richness and diversity of all the sites.
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BACKGROUND AND INTRODUCTION The importance of quaking aspen (Populus tremuloides) to birds and other wildlife in western North America has been well documented (Salt 1957, Flack 1976, DeByle 1985). Aspen habitats typically support much greater bird diversity, richness, and abundance than adjacent habitats (Flack 1976, Winternitz 1980, Mills et al. 2000, Griffis‐Kyle and Beier 2003) or other riparian habitat types (Heath and Ballard 2003). Several bird species demonstrate a strong affinity with aspen, including Northern Goshawk (Accipiter gentilis), Red‐naped and Red‐breasted Sapsuckers (Sphyrapicus nuchalis/ruber), Dusky Flycatcher (Empidonax oberholseri), Warbling Vireo (Vireo gilvus), Swainson’s Thrush (Catharus ustulatus), and MacGillivray’s Warbler (Oporornis tolmiei) (Salt 1957, Flack 1976, Finch and Reynolds 1988, Heath and Ballard 2003, Richardson and Heath 2004). Ground‐nesting birds benefit from an exceedingly thick herbaceous layer and deep leaf litter, which aid in potential for nest concealment (Flack 1976, DeByle 1985). Both primary and secondary cavity nesters benefit from aspen’s susceptibility to heart rot and an associated abundance of cavity‐bearing trees (DeByle 1985, Daily et al. 1993). It is also likely that birds benefit from the increased abundance and diversity of invertebrate prey in aspen stands (Winternitz 1980). The importance of aspen habitats for breeding birds should be considered in the context of this habitat’s documented degradation. California’s aspens are being steadily replaced by conifers due to changes in historic fire regime and grazing pressure (Mueggler 1985; Bartos & Campbell 1998; White et al. 1998, Jones et al. 2005). In the Sierra Nevada, Burton (2000) reported declines in condition and lack of regeneration for a significant number of aspen stands. He cited several potential contributing factors, including fire suppression, livestock grazing, wild ungulate browsing and resulting conifer succession. Richardson and Heath (2004) determined that (among other relationships) aspen‐breeding bird species richness and abundance were positively correlated with lower percent conifer cover, increased herbaceous cover, and increased percent tree‐class aspen cover. They concluded that mature aspen stands with healthy herbaceous communities and limited or no conifer intrusion are optimal habitats for aspen‐breeding birds in the Sierra Nevada of California. As such, there is interest among California’s land managers to restore aspen stands that have been degraded by conifer encroachment (Jones et al. 2005). In an effort to improve quaking aspen (Populus tremuloides) regeneration, the Bureau of Land Management Bishop Field Office is testing three different
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methods to regenerate aspen groves: cutting of lodgepole pines (Pinus contorta), burning and livestock exclusion from the groves. On three plots along Virginia Creek, Mono County, California lodgepole pines were removed in the fall of 2004, 2005 and 2006 (Table 1). In 2007 eight new sites were added, all located in Mono County, California. Four of them had prescribed burns in the spring of 2008; the others will have livestock exclusions. The sites with prescribed burns are located in the Virginia Creek watershed. Three of the livestock exclusion sites are along the Geiger Grade in the Bodie Hills. The other livestock exclusion site is located in the South Fork of Aurora Canyon. In coordination with this effort, BLM and PRBO Conservation Science (PRBO) have collaborated to implement a bird monitoring program to coincide with the active management of these sites. Bird monitoring objectives were:
1. To document species richness, abundance and diversity of breeding birds at treatment and control plots before and after conifer removal, prescribed burns and livestock exclusion.
2. To document special status species that may occupy sites either before or after treatments.
3. To characterize vegetation around nest sites to furnish a basis for vegetation targets for restoration of breeding habitat.
4
STUDY SITE AND METHODS The general study area was located at Virginia Creek and Bodie Hills, Mono County, California (38° 05ʹ N, ‐119° 13ʹ W, Figure 1).
Figure 1. Aspen Stewardship bird monitoring sites, Bodie Hills (A) and Virginia Creek (B), Mono County, CA, 2004 – 2008. 4 and 5 letter plot code correspond to plot codes in Table 1.
Overview
A
B
5
Area Searches We established a total of 18 area search plots from spring 2004 ‐2007 (Table 1, Figure 1). Ten of these were new in 2007 (see Moss 2007). For details on lodgepole thinning treatment and control plots established prior to the spring of 2007, see Heath 2006. Table 1. Area Search information, thinning treatment, prescribed burn and livestock exclusion sites, 2008.
Plot Code
Full Name
BLM Site ID
Plot size (ha)
Type of Treatment
Treatment Date
Pre‐treatment
Bird Monitoring
Post‐treatment
Bird Monitoring
1 TRV1 Virginia Creek 1 Treatment Plot
VC1 0.78 PICO cut Fall 2004 2004 2005, 2006,
2007
2 COV1 Virginia Creek 1 Control Plot
n/a 0.71 None n/a 2004 2006, 2007
3 TRV2 Virginia Creek 2 Treatment Plot
VC3 2.20 PICO cut Fall 2006 2006 2007
4 COV2 Virginia Creek 2 Control Plot
n/a 2.20 None n/a 2006 2007
5 TRV3 Virginia Creek 3 Treatment Plot A
VC2 1.44 PICO cut Fall 2005 ‐‐ 2006, 2007
6 TRV3 Virginia Creek 3 Treatment Plot B
VC2 1.37 PICO cut Fall 2005 ‐‐ 2006, 2007
7 TRV3 Virginia Creek 3 Treatment Plot C
VC2 1.35 PICO cut Fall 2005 ‐‐ 2006, 2007
8 COV3 Virginia Creek 3 Control Plot A
n/a 1.39 None n/a ‐‐ 2006, 2007
9 VIBU1 Virginia Burn 1 W5131D 0.74 Burn Spring 2008
2007 2008
10 VIBU2 Virginia Burn 2 W4130F 1.16 Burn Spring 2008
2007 2008
11 TDOG Tributary to Dog Creek Plot A
W1110 2.13 Burn Spring 2008
2007 2008
12 TDOG Tributary to Dog Creek Plot B
W1110 2.46 Burn Spring 2008
2007 2008
13 TDOG2 Tributary to Dog Creek 2
W211C 1.41 Burn Spring 2008
2007 2008
14 NOPP1 North of Potato Peak 1
B1074 0.54 Livestock Exclusion
‐‐ 2007, 2008 ‐‐
15 NOPP2 North of Potato Peak 2
B1075 0.48 Livestock Exclusion
‐‐ 2007, 2008 ‐‐
16 NOPP3 North of Potato Peak 3
B1072 0.96 Livestock Exclusion
Spring 2007
2007, 2008 2008
17 SFACT South Fork of Aurora Canyon Treatment Plot
P1084A 0.68 Livestock Exclusion
Fall 2008 2007, 2008 ‐‐
18 SFACC South Fork of Aurora Canyon Control Plot
n/a 0.66 None ‐‐ 2007, 2008 ‐‐
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Area search plot boundaries for treatment sites were the same as treatment boundaries established by the BLM. Control sites were chosen to occupy the same area and habitat type as treatment sites. We conducted area search surveys at all 18 plots (Table 1) and followed protocol as described in Ralph et al. (1993). We censused each plot three times during the peak songbird breeding season in 2008 and spaced each of these visits at least 8 days apart (Table 2). We censused each plot for 20 minutes and recorded all birds detected within or flying over the plot boundaries. We also recorded type of detection (song, visual, call) and flocking, foraging and breeding behaviors.
Table 2. Area Search censuses, 2008. Plot Code Visit 1 Visit 2 Visit 3 TRV1 June 9 June 17 June 30 COV1 June 9 June 17 June 30 TRV2 June 8 June 19 June 30 COV2 June 8 June 19 June 30 TRV3 (A, B, C) June 11 June 23 July 2 COV3 June 11 June 24 July 4 VIBU1 June 10 June 24 July 3 VIBU2 June 10 June 24 July 3 TDOG (A, B) June 12 June 20 July 1 TDOG2 June 12 June 20 July 1 NOPP1 June 9 June 17 July 1 NOPP2 June 9 June 17 July 1 NOPP3 June 9 June 17 July 1 SFACT June 11 June 23 July 2 SFACC June 11 June 23 July 2
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Nest Searches and Nest‐site Habitat Characteristics After each morning area search was completed, biologists spent at least 2 hours on the plots attempting to locate as many nests as possible. For each nest found, a biologist took a GPS location of the nest; recorded contents and basic vegetation information (described in Appendix A). We collected location information at all nests using a Garmin Global Positioning System (GPS II+) receiver, recorded in UTM (Universal Transverse Mercator), NAD83 datum. Geographic Data All location data were gathered using a Garmin II‐Plus Receiver in UTM NAD83. Definitions and summary methods Species richness: Number of breeding species detected, summed over three area search visits. Total number detections: Number of individuals detected of all breeding species combined, summed over three area search visits. Species diversity: We used AS_SUM.PRG (Ballard 2005) to calculate breeding species diversity for each area search plot using all detections within each plot summed over three visits. Ballard (2005) used a transformation of Shannon’s diversity index (or 'H , Krebs 1989) denoted N1 (MacArthur 1965). The transformation expresses the data in terms of number of species and thus is more easily interpreted. Expressed mathematically:
N1 = e 'H and ∑=
=
=S
1
ii )1)()(ln( 'Hi
i
-pp
Where S = total species richness and pi is the proportion of the total numbers of individuals for each species (Nur et al. 1999). High index scores indicate both high species richness and more equal distribution of individuals among species. For TDOG and TRV3, which have two and three plots respectively, all plots were summed and then averaged for species richness, diversity and total detections.
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Bird List and Breeding Status We documented all birds detected before, during, and after area search censuses. We determined breeding status for all species detected and ranked species following four criteria of the Riparian Habitat Joint Venture breeding scale, modified from breeding bird atlas criteria (see http://www.prbo.org/calpif/criteria.html.): No evidence of breeding: Species detected on study site, but not during breeding season (e.g. only during winter or spring or fall migration), or detected only once during the breeding season but no territorial behavior observed. Possible breeding: Species encountered singing or acting territorial only once during the breeding season (in suitable habitat). Probable breeding: Singing individual encountered on 2 or more different days of standardized censuses (at least one week apart); territorial behavior noted more than once at the same location (at least one week apart); pair observed in courtship behavior. Confirmed breeding: nest building (except for woodpeckers and wrens), nesting material or fecal sac being carried by adult; dependent juveniles with adults; active territory observed on at least three days (at least one week apart); active nest observed.
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RESULTS AND DISCUSSION Virginia Creek Lodgepole Pine Thinning Treatment We documented 55 species at the Virginia Creek lodgepole pine thinning treatment sites from 2004 ‐2008 and determined breeding status for each (Table 3). New confirmed breeders in 2008 were Dusky Flycatcher on TRV3, Mountain Bluebird on TRV2 and Yellow Warbler on TRV1.
Table 3. Breeding status for all bird species observed at the TRV1/COV1 Virginia Creek study sites 2004 – 2008, TRV2/COV2 and TRV3/COV3 Virginia Creek study sites 2006‐2008. Breeding status: ~ = not detected on site, 0 = detected but not breeding at site, 2 = possible breeder, 3 = probable breeder, 1 = confirmed breeder; codes further described in methods. Breeders highlighted.
Common Name Latin Name TRV1/ COV1
TRV2/ COV2
TRV3/ COV3
Mountain Quail Oreortyx pictus ~ 2 ~ Turkey Vulture Cathartes aura 0 ~ 0 Red‐tailed Hawk Buteo jamaicensis 0 ~ 0 Long‐eared Owl Asio otus ~ ~ 1 Mourning Dove Zenaida macroura 2 ~ 2 Calliope Hummingbird Stellula calliope 2 2 1 Belted Kingfisher Ceryle alcyon ~ 2 ~ Red‐breasted Sapsucker Sphyrapicus ruber 1 1 1 Hairy Woodpecker Picoides villosus 2 2 2 Red‐shafted Flicker Colaptes auratus cafer 1 2 1 Eastern Phoebe Sayornis phoebe ~ 0 ~ Western Wood‐Pewee Contopus sordidulus 1 1 1 Hammondʹs Flycatcher Empidonax hammondii 1 ~ ~ Gray Flycatcher Empidonax wrightii ~ 2 ~ Dusky Flycatcher Empidonax oberholseri 1 3 1 Western Flycatcher Empidonax difficilis or occidentalis 0 ~ ~ Cassin’s Vireo Vireo cassinii ~ 0 ~ Warbling Vireo Vireo gilvus 1 1 1 Stellerʹs Jay Cyanocitta stelleri 3 2 ~ Clarkʹs Nutcracker Nucifraga columbiana 0 0 0 Common Raven Corvus corax 0 0 0 Violet‐green Swallow Tachycineta thalassina 1 1 1 Mountain Chickadee Poecile gambeli 1 3 1 White‐breasted Nuthatch Sitta carolinensis 2 ~ 2 ‐ Continued next page
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Table 3. – Continued
Common Name Latin Name TRV1/ COV1
TRV2/ COV2
TRV3/ COV3
Brown Creeper Certhia americana 1 1 2 House Wren Troglodytes aedon 1 1 1 Rock Wren Salpinctes obsoletus ~ 2 ~ American Dipper Cinclus mexicanus ~ 2 ~ Bushtit Psaltriparus minimus 2 ~ ~ Mountain Bluebird Sialia currucoides 1 1 1 Hermit Thrush Catharua guttatus 2 2 ~ American Robin Turdus migratorius 1 1 1 European Starling Sturnus vulgaris ~ ~ 2 Orange‐crowned Warbler Vermivora celata 0 ~ ~ Yellow Warbler Dendroica petechia 1 3 1 Audubonʹs Warbler Dendroica coronata auduboni 1 3 ~ Townsend’s Warbler Dendroica townsendi 0 0 ~ MacGillivray’s Warbler Oporornis tolmiei 2 3 2 Wilson’s Warbler Wilsonia pusilla 0 0 ~ Western Tanager Piranga ludoviciana 1 1 2 Lazuli Bunting Passerina amoena 2 ~ 2 Green‐tailed Towhee Pipilo chlorurus 1 3 2 Chipping Sparrow Spizella passerina 2 ~ 2 Brewerʹs Sparrow Spizella breweri 2 2 2 Fox Sparrow Passerella iliaca 1 2 2 Song Sparrow Meospiza melodia ~ 2 2 Mountain White‐crowned Sparrow Zonotrichia leucophrys oriantha 2 2 1 Oregon Junco Junco hyemalis oregonus 1 3 2 Brewer’s Blackbird Euphagus cyanocephalus ~ ~ 2 Brown‐headed Cowbird Molothrus ater 1 2 2 Bullock’s Oriole Icterus bullockii ~ ~ 3 Cassinʹs Finch Carpodacus cassinii 1 3 2 House Finch Carpodacus mexicanus ~ ~ 2 Lesser Goldfinch Carduelis psaltria ~ ~ 3 Pine Siskin Carduelis pinus 2 ~ ~ TOTAL 41 38 38
In general species richness, diversity and total detections have increased in the first three years after treatment at TRV1 and TRV2 but slightly decreased in the fourth year after treatment (Table 4). COV1 had the highest species diversity the
11
fourth year after treatment. Overall, bird numbers at COV1 were similar to those on its treatment plot. TRV2 total detections and species richness have stayed essentially the same since treatment, where as COV2 total detections decreased significantly as well as species richness. TRV3 and COV3 had an increase in total detections, species richness and species diversity.
Table 4. Total number of detections, species richness and species diversity at Virginia Creek area search plots, during pre and post treatment years for TRV1 / COV1 and TRV2 / COV2 and two post‐treatment years for TRV3. Sum of all breeding species birds detected during three (20 minute) area search censuses at each plot in each year.
Treatment Control Post‐treatment Post‐treatment
Pre‐treatment Year
1 Year 2
Year 3
Year 4
Pre‐treatment
Year 1
Year 2
Year 3
Year 4
TRV1 / COV1 Total Detections 27 28 43 63 52 24 25 48 36 41 Species Richness 11 10 14 16 12 11 11 14 12 14 Species Diversity 8.92 8.19 11.59 13.33 10.39 8.92 9.67 11.32 8.57 11.67 TRV2 / COV2 Total Detections 46 54 56 ‐‐ ‐‐ 55 52 29 ‐‐ ‐‐ Species Richness 16 19 19 ‐‐ ‐‐ 15 20 14 ‐‐ ‐‐ Species Diversity 12.85 16.22 14.95 ‐‐ ‐‐ 13.41 15.13 11.94 ‐‐ ‐‐ TRV3 / COV3 Total Detections ‐‐ 37 48 ‐‐ ‐‐ ‐‐ 43 59 ‐‐ ‐‐ Species Richness ‐‐ 14 14 ‐‐ ‐‐ ‐‐ 14 19 ‐‐ ‐‐ Species Diversity ‐‐ 10.78 11.58 ‐‐ ‐‐ ‐‐ 10.72 15.94 ‐‐ ‐‐
We located 4 nests in 2004 and 13 nests in 2005 at TRV1 and COV1 (Table 5). With the addition of TRV2, COV2, TRV3 and COV3 in 2006, we found 29 nests. In 2007 we found a total of 30 nests. New species for which we found nests in 2007 were Yellow Warbler, Fox Sparrow, Mountain White‐crowned Sparrow and Calliope Hummingbird. In 2008 we found a total of 23 nests at all six sites combined.
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Table 5. Nests found at lodgepole pine thinning treatment sites, 2004 ‐ 2008.
Species 2004 2005 2006 2007 2008 Long‐eared Owl 0 0 1 0 0 Calliope Hummingbird 0 0 0 1 0 Red‐breasted Sapsucker 0 0 2 4 2 Red‐shafted Flicker 0 0 2 0 2 Western Wood‐Pewee 0 2 2 1 2 Hammondʹs Flycatcher 0 1 0 0 0 Dusky Flycatcher 0 1 0 1 2 Warbling Vireo 1 1 4 2 2 Violet‐green Swallow 0 1 2 2 3 Mountain Chickadee 0 1 3 2 0 Brown Creeper 0 0 2 0 0 House Wren 0 0 2 4 4 Mountain Bluebird 0 0 2 2 3 American Robin 0 1 6 3 1 Yellow Warbler 0 0 0 2 2 Western Tanager 1 1 0 0 0 Fox Sparrow 0 0 0 1 0 Mountain white‐crowned Sparrow 0 0 0 2 0 Oregon Junco 2 3 0 2 0 Cassinʹs Finch 0 1 1 1 0 Total 4 13 29 30 23
Nests were built in lodgepole pine, aspen, on the ground (and concealed by leaves, logs, or downed branches), shrubs or in aspen or lodgepole snags. Nests that we found most frequently were those built by cavity and canopy nesting species (Figure 2). We found the fewest numbers of nests built by shrub nesting species, likely due to the fact that most sites tended to lack a shrub understory and that shrub nests are typically more difficult to find. Ground nests we found were those of the Oregon Junco and Mountain White‐crowned Sparrow.
13
31%
44%
11%
9%5%
Canopy Cavity Generalist Ground Shrub
Figure 2. Nest types for all nests found at Virginia Creek lodgepole pine thinning treatment sites 2004‐2008.
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Virginia Creek Prescribed Burn Treatment We documented 40 species at the Virginia Creek burn study sites in 2007 and 2008 and determined breeding status for each (Table 6). We detected 10 new species in 2008, shown in bold. Breeding species are highlighted. The only new confirmed breeder is Cassin’s Finch.
Table 6. Breeding status for all bird species observed at the TDOG, TDOG2, VIBU1 and VIBU2 study sites 2007 and 2008. Breeding status: ~ = not detected on site, 0 = detected but not breeding at site, 2 = possible breeder, 3 = probable breeder, 1 = confirmed breeder; codes further described in methods. Common Name Latin Name TDOG TDOG2 VIBU1 VIBU2 California Gull Larus californicus 0 ~ ~ ~ Red‐tailed Hawk Buteo jamaicensis 0 ~ ~ ~ American Kestrel Falco sparverius 2 2 2 ~ Mourning Dove Zenaida macroura 2 ~ ~ ~ Calliope Hummingbird Stellula calliope ~ ~ 2 ~ Red‐breasted Sapsucker Sphyrapicus ruber ~ ~ 2 2 Red‐shafted Flicker Colaptes auratus cafer 2 1 2 ~ Western Wood‐Pewee Contopus sordidulus 2 ~ 2 2 Gray Flycatcher Empidonax wrightii ~ ~ ~ 2 Dusky Flycatcher Empidonax oberholseri 2 2 2 1 Warbling Vireo Vireo gilvus 2 ~ ~ ~ Clarkʹs Nutcracker Nucifraga columbiana ~ ~ 2 ~ Common Raven Corvus corax 0 ~ ~ ~ Violet‐green Swallow Tachycineta thalassina 2 ~ 2 2 Mountain Chickadee Poecile gambeli 2 ~ 2 ~ House Wren Troglodytes aedon 2 ~ 2 2 Rock Wren Salpinctes obsoletus ~ ~ 2 ~ Mountain Bluebird Sialia currucoides 2 ~ 2 2 Sage Thrasher Oreoscoptes montanus 2 2 ~ ~ American Robin Turdus migratorius 2 2 2 1 European Starling Sturnus vulgaris ~ ~ 2 ~ Yellow Warbler Dendroica petechia 2 ~ 2 ~ Western Tanager Piranga ludoviciana 2 ~ ~ 2 Lazuli Bunting Passerina amoen 2 ~ ~ ~ Green‐tailed Towhee Pipilo chlorurus 3 3 2 2 Spotted Towhee Pipilo maculatus ~ 2 ~ ~ Brewerʹs Sparrow Spizella breweri 1 3 2 2 Vesper Sparrow Pooecetes gramineus 2 2 2 ~ ‐table cont. ‐
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Table 6 cont. Breeding status for all bird species observed at the TDOG, TDOG2, VIBU1 and VIBU2 study sites 2007 and 2008. Breeding status: ~ = not detected on site, 0 = detected but not breeding at site, 2 = possible breeder, 3 = probable breeder, 1 = confirmed breeder; codes further described in methods. Common Name Latin Name TDOG TDOG2 VIBU1 VIBU2 Savanna Sparrow Passerculus sandwichensis ~ ~ 2 ~ Fox Sparrow Passerella iliaca 2 ~ ~ ~ Sage Sparrow Amphispiza belli 2 ~ ~ ~ Song Sparrow Meospiza melodia ~ ~ 2 ~ White‐crowned Sparrow Zonotrichia leucophrys oriantha 2 2 2 2 Western Meadowlark Sturella neglecta 2 ~ ~ 2 Brewer’s Blackbird Euphagus cyanocephalus ~ ~ 2 2 Brown‐headed Cowbird Molothrus ater 2 2 2 ~ Bullock’s Oriole Icterus bullockii ~ 2 2 2 Cassin’s Finch Carpodacus mexicanus 1 ~ 2 2 Lesser Goldfinch Carduelis psaltria ~ 2 ~ ~ Pine Siskin Carduelis pinus ~ ~ ~ 2 TOTAL 27 13 25 17
TDOG and TDOG2 both had a decrease in total detections post‐treatment and are lower than detections on the thinning treatment plots (Table 7). Species richness decreased significantly on TDOG2 post‐treatment. VIBU1 had a slight increase in total detections, species richness and diversity. Total detections on VIBU2 on the other hand more than doubled and species richness and diversity came close to being twice as high in the post‐treatment year.
16
Table 7. Total number of detections, species richness and species diversity at Virginia Creek burn area search plots, during pre‐treatment year 2007 and post‐treatment 2008 for TDOG, TDOG2, VIBU1 and VIBU2. Sum of all breeding species birds detected during three (20 minute) area search censuses at each plot in each year.
Pre‐treatment Post‐treatment
TDOG Total Detections 46 34 Species Richness 13 14 Species Diversity 9.22 10.1 TDOG2 Total Detections 48 34 Species Richness 12 7 Species Diversity 6.99 5.61 VIBU1 Total Detections 20 28 Species Richness 12 13 Species Diversity 10.44 10.73 VIBU2 Total Detections 12 25 Species Richness 7 12 Species Diversity 5.47 10.33
We found a total of seven nests at all Virginia Creek burn treatment plots (Table 8). Brewer’s Sparrow nests were built in big sagebrush; the American Robin and Dusky Flycatcher nests and the Red‐shafted Flicker nest cavity were built in live quaking aspen. In 2008 we found a Cassin’s Finch nest in the canopy of a Jeffrey pine. In 2007 and 2008 the Red‐shafted Flicker used the same cavity on TDOG2, the only cavity we could detect on the plot. We spent the same amount of time nest searching on the burned plots as we did on the treatment but the number of territorial species is significantly lower on these plots.
17
Table 8. Nests found at Virginia Creek prescribed burn treatment sites, 2007 and 2008. Species 2007 Red‐shafted Flicker 2 Dusky Flycatcher 1 American Robin 1 Brewer’s Sparrow 2 Cassin’s Finch 1 Total 7
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Bodie Hills Livestock Exclusion Treatment We documented 32 species at Bodie Hills sites in 2007 and 2008 and determined breeding status for each (Table 9). New species for 2008 are Rock Wren and House Finch. New Species are in bold. Breeders are highlighted.
Table 9. Breeding status for all bird species observed at the NOPP1, NOPP2, NOPP3, SFACT and SFACC study sites 2007. Breeding status: ~ = not detected on site, 0 = detected but not breeding at site, 2 = possible breeder, 3 = probable breeder, 1 = confirmed breeder; codes further described in methods.
Common Name Latin Name NOPP1 NOPP2 NOPP3
SFACT/SFACC
Mountain Quail Oreortyx pictus ~ ~ 2 ~ Greater Sage‐Grouse Centrocerus urophasianus ~ ~ 2 ~ American Kestrel Falco sparverius 2 ~ 2 ~ Mourning Dove Zenaida macroura ~ ~ 2 ~ Red‐breasted Sapsucker Sphyrapicus ruber ~ ~ ~ 2 Hairy Woodpecker Picoides villosus ~ ~ ~ 2 Red‐shafted Flicker Colaptes auratus cafer 2 2 ~ 2 Dusky Flycatcher Empidonax oberholseri 2 1 1 1 Warbling Vireo Vireo gilvus 2 ~ ~ 1 Stellerʹs Jay Cyanocitta stelleri ~ ~ ~ 2 Pinyon Jay Gymnorhinus cyanocephalus 2 2 ~ ~ Clarkʹs Nutcracker Nucifraga columbiana ~ ~ ~ 2 Mountain Chickadee Poecile gambeli 2 ~ ~ 2 House Wren Troglodytes aedon 1 2 ~ 1 Rock Wren Salpinctes oboletus ~ ~ 2 ~ Mountain Bluebird Sialia currucoides 1 1 1 1 Sage Thrasher Oreoscoptes montanus 2 ~ 2 ~ Hermit Thrush Catharua guttatus 2 ~ ~ 2 American Robin Turdus migratorius 2 ~ 2 2 Orange‐crowned Warbler Vermivora celata ~ ~ ~ 2 Audubonʹs Warbler Dendroica coronata auduboni ~ ~ ~ 2 Green‐tailed Towhee Pipilo chlorurus 2 2 2 ~ Spotted Towhee Pipilo maculatus ~ ~ 2 2 Brewerʹs Sparrow Spizella breweri 2 2 2 ~ Vesper Sparrow Pooecetes gramineus ~ 2 ~ ~ Fox Sparrow Passerella iliaca ~ ~ 2 2 Oregon Junco Junco hyemalis oregonus ~ 2 2 2 Brewer’s Blackbird Euphagus cyanocephalus 2 ~ ~ ~ Brown‐headed Cowbird Molothrus ater 2 ~ ~ 2 Pine Siskin Carduelis pinus ~ ~ ~ 2 Black‐headed Grosbeak Pheucticus melanocephalus ~ ~ ~ 2 House Finch Carpodacus mixicanus ~ ~ 2 ~ TOTAL 15 9 15 20
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SFACT had the highest species richness and diversity of all livestock exclusion sites even though it had a slight decrease in the second year of pre‐treatment (Table 10). This is the only site with running water, which could contribute to a higher species richness and diversity in the area. NOPP3 (the only site with post‐treatment) is the only one with a significant increase in total detections but not much change in species richness and diversity. NOPP1 had the most drastic decrease in species richness and diversity between first and second year of pre‐treatment; it was reduced by one third.
Table 10. Total number of detections, species richness and species diversity at Bodie Hills area search plots, during pre treatment year 2007 and 2008 for NOPP1, NOPP2, NOPP3, SFACT and SFACC. Only the fence around NOPP3 was completed before spring 2008, resulting in the first post‐treatment year in 2008. Sum of all breeding species birds detected during three (20 minute) area search censuses at each plot.
Pre‐treatment
1. Year Pre‐treatment
2. Year Post‐treatment
1. Year
NOPP1
Total Detections 14 9 ~
Species Richness 9 3 ~ Species Diversity 7.71 2.62 ~ NOPP2 Total Detections 11 14 ~ Species Richness 6 4 ~ Species Diversity 4.92 3.31 ~ NOPP3 Total Detections 19 ~ 31 Species Richness 9 ~ 9 Species Diversity 7.29 ~ 7.08 SFACT Total Detections 38 33 ~ Species Richness 13 9 ~ Species Diversity 10.84 7.74 ~ SFACC Total Detections 21 33 ~ Species Richness 10 8 ~ Species Diversity 8.37 7.08 ~
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We found a total of 19 nests on the livestock exclusion plots (Table 11). All but three nests were found in mature aspen trees. The three nests not in mature aspen were of a Mountain Bluebird and a House Wren, placed in downed aspen snag cavities, and one Dusky Flycatcher nest in a Ribes spp.
Table 11. Nests found on all cut sites combined, 2004 ‐ 2008. Species 2007 Red‐breasted Sapsucker 1 Dusky Flycatcher 6 Warbling Vireo 3 House Wren 3 Mountain Bluebird 6 Total 19
Aspen cover is very scant at both NOPP1 and NOPP2, where we counted a total of 5 and 38 aspen trees respectively, and where no regeneration is occurring. Even so, birds clearly used the existing trees for nesting sites. These data indicate the importance of even a few aspen trees for breeding birds. We expect bird diversity to increase once livestock are excluded and shrub and herbaceous cover have a chance to recover. If bird use at these sites is to persist over the long term, regeneration of aspen will need to occur in order to replace the decadent trees that now exist there.
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ACKNOWLEDGEMENTS
BLM Bishop Field Office funded this monitoring effort. Anne Halford, Steven Nelson, Joy Fatooh and Dale Johnson, in particular, were very supportive. Colin Woolley assisted with field work. This is PRBO Contribution # 1669
LITERATURE CITED Ballard, G. 2005. AS_SUM.PRG. Area search data summary program. PRBO Conservation Science, 4990 Shoreline Hwy., Stinson Beach, CA 94971. Bartos, D. L., and R. B. Campbell Jr. 1998. Decline of Quaking Aspen in the interior West ‐ examples from Utah. Rangelands 20:17‐24. Burton, D. Aspen delineation project summary, El Dorado National Forest, October 2000. Repport to the USDA Forest Service, El Dorado National Forest. 2070 Orange Dr., Penryn, CA 95663. Daily, G. C., P. R. Ehrlich, and N. M. Haddad. 1993. Double keystone bird in a keystone species complex. Proceedings of the National Academy of Science, USA 90:592‐592. DeByle, N. V. 1985b. Wildlife. Pages 135‐152 in N.V. DeByle and R.P. Winkour, editors. Aspen: Ecology and Management in the Western United States. United States Forest Service GTR‐RM‐119. Flack, J. A. D. 1976. Bird populations of aspen forest in western North America. Ornithological Monographs 19:1‐97. Finch, D. M., and R. T. Reynolds. 1988. Bird response to understory variation and conifer succession in aspen forests. Pages 87‐95 in J. Emerick, F. S.Q, L. Hayden‐Wing, J. Hodgson, J. W. Monarch, A. Smith, O. Thorne, and J. Todd, editors. Proceedings III: Issues and Technology in the Management of Impacted Wildlife. Thorne Ecological Institute, Boulder, CO.
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Griffis‐Kyle, K. L., and P. Beier. 2003. Small isolated aspen stands enrich bird communities in southwestern ponderosa pine forests. Biological Conservation 110:375‐ 385. Heath, S. K., 2007. Bird monitoring of the Bureau of Land Management Bishop Resource area Aspen Stewardship Project. Results of the 2006 field season with comparisons to 2004 and 2005. Heath, S. K. and Ballard, G. 2003. Patterns of Breeding Songbird Diversity and Occurrence in Riparian Habitats of the Eastern Sierra Nevada. in California Riparian Systems: Processes and Floodplain Management, Ecology, and Restoration, P. M. Faber (Ed.), Riparian Habitat and Floodplains Conference Proceedings, Riparian Habitat Joint Venture, Sacramento, CA. pp 21 – 34. Jones, B. E., T. H. Rickman, A. Vazquez, Y. Sado, and K. W. Tate. 2005. Removal of Encroaching Conifers to Regenerate Degraded Aspen Stands in the Sierra Nevada. Restoration Ecology Vol. 13, No. 2, pp. 373–379 Krebs, C.J. 1989. Ecological methodology. Harper and Row Publishers, New York, New York: 654 pp. Macarthur, R.H. 1965. Patterns of species diversity. Biological Reviews 40: 510 ‐
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Mills, T. R., M. A. Rumble, and L. D. Flake. 2000. Habitat of birds in ponderosa pine and aspen/birch forest in the Black Hills. United States Forest Service RMRSRP‐21. Mueggler, W. F. 1985. Forage. Pages 129–134 in N. V. Debyle and R. P. Winokur, editors. Aspen: ecology and management in the western United States. USDA Forest Service General Technical Report RM‐119. United States Forest Service Rocky Mountain Research Station, Fort Collins, Colorado. Nur. N, Jones, S.L. Jones, and G. R. Geupel. 1999. A statistical guide to data analysis of avian monitoring programs. U.S. Department of the Interior, Fish and Wildlife Service, BTP‐R6001‐1999, Washington D.C. Ralph, C. J., G. R. Geupel, P. Pyle, T. E. Martin, and D. F. DeSante. 1993. Field Methods for Monitoring Landbirds. United States Forest Service PSW‐GTR‐144.
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Richardson, T. W. and Heath, S. K. 2005. Effects of conifers on aspen‐breeding bird communities in the Sierra Nevada. Transactions of the Western Section of the Wildlife Society 40:686‐81. Salt, G. W. 1957. Analysis of avifaunas in the Teton Mountains and Jackson Hole, Wyoming. Condor 82:373‐393. Stata Corporation. 1999. Stata Statistical Software, Release 6.0. Stat Corporation, College Station, TX. White, C. A., C. E. Olmsted, and C. E. Kay. 1998. Aspen, elk, and fire in Rocky Mountain National Parks of North America. Wildlife Society Bulletin 26:449–462. Winternitz, B. L. 1980. Birds in aspen. Pages 247‐257 in R.M. Degraff, editor. Workshop proceedings on management of western forests and grasslands for nongame birds. United States Forest Service GTR‐INT
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Appendix A, non monitored Nest Card Non_monitored Nests. PRBO Eastern Sierra. Project:_____________________
Date Species Station Observer Location Data E N Datum UTM NAD83
Contents
(B%, E#, Y#) Age of Young BHCO
Contents Age of BHCO
Clumpwidth (m) Perpwidth (m) Maxclumpht (m) Plantht (cm) Htfrgrd (cm)
Plantsp1 Plantsp2 Nstcncl1 Nstcncl2
DBH (cm) Dist_edge (cm) Canopycov Concealab Concealbe
Concealno Concealso Concealea Concealwe Comp. dir % alive
Distance to Road:
Notes: