Conserving Biological Diversity and the Conservation Reserve Program

Growth und Chunge Vol. 26 (Summer 19%). pp. 383-404

Conserving Biological Diversity and the Conservation Reserve Program

SUSANNE SZENTANDRASI STEPHEN POLASKY ROBERT BERRENS JEROME LEONARD

ABSTRACT The lack of success with the endangered species approach to conserving biodiversity has led to calls for programs that are designed to maintain viablc populations of species before they become endangered. While wildlife preserves are an important component of biodiversity conservation, effective protection of species will often take place on land that is used primarily for purposes othcr than wildlife habitat. The suitability of these lands as wildlife habitat can be influcnccd by government programs. An important example of a program affecting ;igricultiird land use is the Conservation Reserve Program (CRP), which is the largest I;md retirement program in US. history. The expectcd down-sizing of the program in the mid 90s sharpens the need for improved targeting if the program is to continue t o provide wildlife benefits. This paper studies how well the current CRP fares as R hiodivcrsity conservation program and suggests possible ways to target the CRP to conserve wildlife habitat. A methodology for tackling this task in Oregon is outlined.

Introduction I l I X l i IS WIDESPRIiAI) CONCERN THAI' HUMAN ACTIVIl'IES, MOST NOTABLY T habitat dcstruction, are causing a decline in biological diversity. Nurncrous

authors havc callcd for a major cffort to protect biodiversity (c.g., Noss and Coopcrridcr 1994; Wilson 1992). In the U. S . there are currently 955 species listcd as thrcatcncd or cndangcrcd (U.S. Fish & Wildlife Service 1995), with ovcr 3,000 candidate spccics awaiting further study (U.S. Fish & Wildlifc Scrvicc 1993). Only a fraction of thc listcd species have recovery plans and only five spwics havc rccovcrcd sufficicntly to havc been rcrnoved from the cndangcrcd and thrcalcned list (Wilcove et al. 1993). Saving specics on the

Susanne Szentnndrusi is u docroral student and Stephen Polasky is an associate professor of agricultural and resource economics ut Oregon State University, Corvullis; Robert Berrens is an assistant professor of economics at the Universily of New Mexico, Albuquerque, and Jerome Leonard is a doctoral sludenl in Fisheries und Wildlife at Oregon State University.

Submitted Oct. 1994; revised June 1995. 0 1995, Center for Business and Economic Research, University of Kentucky

384 GROWTH AND CHANGE, SUMMER 1995

brink of extinction is usually expensive and often not succcssful (Tear ct al. 1993). Rccovcry plans oftcn have disproportionate impacts on rural areas (e.g., Watcrs ct al. 1994).

Thc lack of succcss with the endangered spccics approach to conserving biodiversity has Icd to calls for a morc proactive program that targets protccting intact habitats on which thc survival of species depends (c.g., Scott et al. 1993). From a policy pcrspcctivc, the protcction of habitat is a land usc issue. The probability of survival of an assemblage of spccies depends on the condition of the habitat, which is a function of land use. The acquisition of pristine habitat for wildlife reserves is the primary focus in many conscrvation efforts. Currcntly, about four pcrccnt of the world’s land and about nine pcrccnt of U.S. land is in a highly protccted status (World Rcsourccs Institutc 1990). Budget constraints of public agencies as well as private organizations (cg., Nature Conscrvancy o r Ducks Unlimited) limit the acquisition of new reserves as wcll as thc degrcc of protcction for existing reserves. While wildlife preserves are an important component of biodiversity conservation, effective protection of large numbcrs of spccics will necessarily take place on land whose primary designation and usc is not for wildlife conservation. About half of the currently listed cndangcrcd or thrcatcncd spccics dcpcnd almost exclusively on habitat on private land (McKinncy ct al. 1993). Accomplishing conscrvation goals on thcse lands will oftcn rcquirc thc use of inccntivcs to privatc landowners or usc of a rcgulatory policy framcwork (c.g., Endangered Spccics Act or Clean Watcr Act) ratticr than land purchasc for conscrvadon purposcs by thc government.

Land usc dccisions on private land arc affected by a variety of federal, slate, and local govcrnmcnt policics. An important policy program affccting agricultural land usc is the Conscrvation Reserve Program (CRP). Undcr thc prograin, crodiblc or cnvironrnentally scnsitivc crop lands arc rctircd from crop production. Fanners arc paid by thc U.S. Dcparlmcnt of Agriculturc (USDA) to enroll acrcs in thc program. Beginning in the mid-1990s over 22 million acres of CRP land will comc up for contract renewal. According to Heimlich and Osborn (1993):

“Givcn the currcnt budgetary environment, extension of all CRP contracts at an annual cost of $ I .8 billion is not a realistic option ... accentuating thc need to aggrcssivcly targct CRP land to maximizc conscrvation and environmental bcncfits.”

The purposc of this papa is to cxamine how wcll thc current CRP fares as a biodiversity conscrvation program and to suggcst possible ways to target the CRP to conserve biodivcrsity. Thc following scction rcvicws thc history and status of thc CRP and dclails thc benefits of thc currcnt program lor wildlife

CONSERVATION RESERVE PROGRAM 385

conservation. The third section investigates opportunities to target the CRP for biodiversity conservation. The next section comments on empirical tools and methods for studying this issue, and the last section contains some concluding remarks.

The Conservation Reserve Program Program description. The CRP cumulatively has enrolled 36.5 million acres

of cropland over the past decade. The CRP was established under Title XI1 of the Food Securities Act (FSA) of 1985 (P.L. 99-198). The U.S. Department of Agriculture (USDA) was directed to formulate and implement a conservation rescrvc; the stated objective of the program was to assist owners and operators of highly erodible cropland in “conserving and improving the soil and water resources on their farms and ranches” (99 Stat. 1509). Passage of the FSA was motivatcrl by concern for farm support (prices and income) in the presence of commodity surpluses, and concern for widespread soil erosion (Luzar 1988; Rcichcldorfcr and Boggess 1986). The CRP considerably expanded previous agricultural conservation programs (Ervin 1993).

The original program goal was to enroll 40-45 million acres between 1986 and 1990. Highly erodible croplands were classified by the USDA and the Soil Conscrvation Service (SCS) as having excessive average annual rates of erosion relative to cstablishcd soil loss tolerance levels (c.g., under the universal soil loss equation). The CRP also allowed the inclusion of lands that were not highly erodible, but posed an “off-fmn environmental threat” (99 Slat. 1509). In practice, originally only highly erodible land was eligible for enrollment. In 1988, eligibility enrollments were expanded to include land adjacent to streams, lakcs, and estuaries, so-called filter strips, as well as cropped wetlands. Filter strips havc thc potential to rcducc sedimentation as well as pesticide and fertilizer runoff, thereby improving water quality (Whitworth and Martin 1990). To the cxtcnt practicable, thc 1985 FSA directed that not less than one-eighth of all lands cnrollcd in the CRP were to be planted with trees (99 Slat. 1511). This program goal has never been fully achieved.

The CRP provided for voluntary long-term cropland retircment. During specific sign-up periods, landowners are offered the option of entering into a ten year contract with the government. In return for retirement of highly erodible and other cnvironmcnlally sensitive lands, the USDA pays participants an annual per acre rcnt, and onc-half the costs of establishing a permanent vegetative land cover that cannot be harvested or grazed. Annual rental payments per acre are determined by a bid submitted by the land owner, which can either be accepted or rejccteti by the government. To date, average annual rental payments have bccn approximately $50 per acre.

386 GROWTH AND CHANGE, S U M M E R 1995

Undcr the FSA, in determining the acceptability of any bid the USDA could: (1) consider the extent of erosion and productivity of the acrcagc, (2) consider opportunities to provide shelterbelts, filter suips, and permancnt vegetated stream borders, (3) establish alternative criteria for statc and regional variations, and (4) providc priority to owners and operators under the highest dcgrec of economic strcss (c.g., tightening of agricultural credit, and thc relation between production costs and agricultural commodity prices). In implcmenting the CRP, the USDA was dircctcd to utilize the services of its own Soil Conservation Service and Forest Scrvicc, as wcll as the U.S. Fish and Wildlife Service, state forestry and fish and game agcncies, soil conservation districts, and land-grant colleges (99 Stat. 1515).

In summary, although the provisions of the original CRP cstablishcd the protcction of soil and water resources on highly crodiblc lands as the primary objcctivc, additional conccrns included the protection of othcr environmentally sensitive lands and economic farm support. Thus, the original CRP was gcncrally intcrprctcd broadly to provide agricultural commodity support, and cnvironmcntal protcction, including wildlife habitat (e.g., Luzar 1988; Rcichcl- dorfcr and Boggcss 1986; Young and Osborn 1990).

This broad inlcrpretation was given more specific implementation in 1990 amendmcnls to thc FSA, which included dircct consideration of the provision of wildlife habitat. Spccifically, the Food Securitics Act of 1985, and ils Conscrva- Lion Rcscrvc Program, were amendcd by the Food, Agriculture, Conscrvation and Trade Act (FACTA) of 1990 (P.L. 101-624). Thc CRP provisions of the 1990 FACTA cxtcndcd the cumulative enrollment goal of 40-45 million acres through 1995. This included the roughly 34 million acres enrolled Lhrough nine sign-ups under the FSA.

In determining the acceptability of any contract offers (or bids), the revised CRP may: (1) consider the extent of improverncnt in soil resources, water quality of wildlife habitat, or other environmental benefits; and (2) establish alternative criteria by different states and regions, based upon the extent lo which water quality and/or wildlife habitat may be improved or erosion may be abated. Under FACTA, a numbcr of broad conservation priority arcas for the CRP wcrc also establishcd, specifically Long Island Sound, Chesapcake Bay, and the Great Lakes Rcgion.

Subject to these provisions, the USDA has changed the bidding system for enrolling CRP lands. Under the revised CRP bid acceptance procedures, bids arc initially scrccncd at both the local county and national levels for general cligibility rclalivc to accepted land rental rates. Then, remaining bids are further cvaluatcd using an environmental benefits index (EBI) calculation. Bids are rankcd ordinally according to their EBI per federal dollar enrollment cost. The


EBI calculations arc rudimentary and loosely based on estimated improvements in thc following seven areas: (1) surface water quality, (2) groundwater quality, (3) soil productivity, (4) conservation compliance assistance, (5) tree planting, (6) assistancc to dcsignated statc water quality impairment areas, and (7) conscrvation priority areas (U.S. Gcncral Accounting Office (GAO) 1993). While discussed generally in the literature and by the USDA (e.g., Heimlich and Osborn 1993; Osbom 1994), the exact construction of an individual EBI is always unclcar; a widc variety of data is used across the categories, and the wcights on thc various components of the EBI have not been made public. Morcovcr, thc total impact of the revised bid acceptance procedures has been ncgligiblc. To tlatc, only about 2.5 million (of the 36.5 million total) acres have hccn cnrollcd through thrcc sign-ups under the 1990 CRP program revisions. Howcvcr, tlic pcrcciilagc of watcr rclatcd erosion rcduction enrollments and cnrollmcnts plantcd in trccs have bccn increasing (Heimlich and Osborn 1993).

In October of 1995, the fist CRP contracts, covering approximately 2 million acrcs, will cxpirc. An additional 22 million acres expire in 1996 and 1007. According to a survey conduclcd by thc Soil and Water Conservation Socicty, i t is cxpcctcd that about half of thc rctircd CRP acreage will be rcturncd to cropland production, one-third will be left for livestock forage or hay production, whilc the remainder will maintain existing uec cover or bc maintaincd as wildlifc habitat (Nowak et al. 1991). Of course, expectations for post-CRP land-usc dccisions differ by region (e.g., Skaggs et al. 1994), and are an important gcogrnphical consideration in futurc program revisions. The current fiscal situation of thc government makes it very unlikely that all CRP conmcts will bc cxtcnded upon expiration (Osborn 1994). Adding additional pressure on possiblc rcncwal is cvidcnce that the CRP has not been particularly cost effective on a strict acrcagc cnrollmcnt basis (U.S. GAO 1993; Reicheldorfer and Boggess 19x6; Smith 1995).

Finally, considcration of CRP acreagc rencwal must be done in the context of national policy dcbatcs over pcnding agricultural legislation (Zinn 1993). Howcvcr, cntcring thc second half of 1995, the status of the multi-year “1995 Farm Bill” rcmains unclear. Relative to the 1985 passage of the FSA and the original CRP, thc pressure for agricultural commodity support has lessened (Ervin 1993). As of May 1995, initial congressional hearings have been held on thc 1995 Farm Bill, with more scheduled. Widely discussed issues include substantial down-sizing of the CRP, allowing limited grazing on CRP lands tied Lo lowcr pcr acre payments, and improved environmental targeting. McKenzie and Rilcy (1995) call for explicitly elevating wildlife concerns and habitat provision on agricultural lands in the 1995 Farm Bill.


1:‘nvironmental and wildrife benefits of the CRP. Several studies have attcrnptcd to quantify thc cnvironmcntal and wildlifc bcncfits of the CRP. Thcse bcncfits arc difficult to assess accuratcly and thc rcsults should bc intcrprctcd as suggcstivc rathcr than dcfinitivc. Overall, the total environmental and wildlife bcncfits for a full 45 million acre CRP were projcctcd to be between $6.0 to 13.6 billion (Ribaudo ct al. 1989; Young and Osborn 1990). The largcst share of thcsc bcncfits was from improvcd wildlife habitat. Wildlife bcncfits alonc from thc CRP wcrc cstirnatcd to bc $3.8 billion (Ribaudo et al. 1989; Young and Osborn 1990; Langncr 1989). Thcse figures only includc small gamc hunting activity. Non-consumptive activitics such as bud watching, naturc photography, hiking, and picnicking, which are more difficult to measurc, were not included in thc cstimatcs.

Dcspitc thc rclativcly large potcntial wildlife rccreation benefits cited in thc prcvious paragraph, thcrc is somc cvidcncc that actual benefits may be lower. An ovcrwhclming majority of CRP participants reported that they would no1 consider allowing public access onto their CRP lands (Millcr and Bromcly 1989) dcspitc the fact that allowing huntcr access can provide significant supplcmcntal income (c.g., Sicgcl and Johnson 1991; Langner 1989). In Virginia, only four pcrccnt of CRP land was leased to hunters or hunt clubs.

Publishcd rcscarch by biologists on the cffcct of thc CRP on wildlife population levcls is rclatively limilcd. Grassy areas near cropland serve as habitat for many spccics. Migratory and non-migratory birds, small mammals, and big gamc use these areas for ncsting covcr, food, wintcr covcr, and corridors for movcmcnt. Preliminary results indicate that thc CRP has incrcascd the population of scvcral species (Johnson and Schwarw 1993a, 1993b). In Minncsota, North Dakota, Ohio, and South Dakota, the CRP has more than doublcd ring-ncckcd pheasant (Phasiunus cofchicus) populations (Wildlife Managcmcnt Institutc 1994). Watcrfowl nest succcss in an area of North Dakota and Minncsola was 23.1 pcrccnt on CRP lands compared to 8.2 percent on U.S. Fish and Wildlifc Service’s waterfowl production areas with similar vegetative covers (Kantrud 1993). Some songbirds such as lark bunting (Cafumospiza mcfannr:orys), grasshoppcr sparrow (Ammodrumus savannarum), clay-colored sparrow (Spizella pulfidu), bobolink (Dolichonyx oryzivorus), dickcissel (Spiza umcricunu), and Baird’s sparrow (Ammodrumus hairdzi) arc more common in CRP ficlds than in cropland (Johnson and Schwartj! 1993b). Whitworth and Martin ( I 990) found that improved water quality from CRP filtcr strips has bcncfittcd ccnain types of fish and macroinvertebrates in eight streams of North Carolina and Indiana. No published rcsearch of the cffccts of CRP on big game is availablc. Howcvcr, it is belicved that mulc deer, elk, and white-tailed deer have hcncfittcd from the CRP.


Targeting the CRP to Conserve Biodiversity Since the CRP affccls land use on a large amount of land, there exisls the

potcntial [or the CRP to be used to conserve biodiversity. The term biodiversity can bc applicd at the genetic, species, ecosystem, and landscape levels and may rcfcr to the composition and structure of the members of a collection or to the proccsscs of a systcm (Noss and Cooperrider 1994). In theory, it would bc idcal to mcasurc thc contribution of changes in the CRP on biodiversity in all its dimensions but this would rcquire far more information and a greater understand- ing of ecological processes than currently exists. This paper focuses on biodiversity at thc spccics level. Much of the recent work in conservation biology has takcn a similar focus. For example, in literature on conservation reserve site selection, the objcctive is to choose reserve sites to maximize the number of species represented in a selected area (e.g., Margulcs et al. 1988; Pressey et al. 1993; Kcrshaw el al. 1994; Williams et al. 1995). Instead of using species richness (i.c., the number of species), species may be weighted according to importancc, usually mcasurcd in terms of taxonomic uniqueness (c.g., Vane- Wright el al. 1991; Faith 1992; Solow el al. 1993). Species weights could also dcpend upon the economic importance of the species or the degree of threat faced by the species. The basic data needed to study species diversity arc species inventories by location, which exist at least for some taxa in some areas. The application in the next section uses species inventory information collected for Oregon.

The CRP may also yield valuable benefits, even for a species that has low probability of extinction, if it contributes to increasing the population of the species. The goal of traditional wildlife management programs was to maintain or increase the population of certain valuable species. The wildlife benefits estimates from the CRP quoted in the previous section were for increased hunting opportunities derived from increases in populations of game species.

The current CRP and biodiversity conservation. In terms of conserving spccics diversity, as mcasured by species richness, the current CRP is of limited utility. Most of the beneficial wildlife effects of the current CRP are increases in populalions of spccics that are not in imminent dangcr of extinction. Exccptions include three species or subspecies, the greater prairie chicken (7ympcinrrchus cupido), which was liskd on the Colorado state endangered spccics list, thc Columbian sharp-tailed grouse (7ympanuchus phasiunellus columhianus), which is a candidate for listing on the fcderal thrcatcncd and cndangcred spccics lisL5, and the pgymy rabbit (Bruchylugus iduhoensis), which is currcntly listcd as threatened and proposed for listing as endangered by the statc of Washington.


One factor limiting the ability of the CRP to contribute to conserving species (is., preventing extinctions) is the geographic distribution of CRP lands. The bulk of CRP lands to date have been in the Plains region, particularly the Northern Plains. Most of the documented wildlife effccts dcscribed in the second section are for the Northern Plains. Figure 1 shows a map of the conccntration of CRP lands nationwide. The CRP acrcage for each slate is given in Tablc 1. While the CRP lands are concentrated in the Plains, threatened and cndangcrcd specics arc concentratcd in southern and coastal states. Figure 2 shows a map listing the number of threatened and endangered species by state. For thc 50 states plus Puerto Rico the enrolled CRP acreage and divided by the total land arca in the state (CRP acreage per unit area) werc computed, as well as the numbcr of threatened and endangered species divided by total land area (spccics per unit area). It is intcresting to note that there is a negative correlation (-0.263) bctwccn CRP acreage per unit area and spccies per unit area. CRP lands currently arc largctcd to regions that have relatively few threatened and cndangcrcd spccics.

A sccond factor limiting the ability of the CRP lands to contribute to conserving species is that CRP lands by definition are former agricultural land. Virtually all CRP land is converted into grassland. Only species that depend upon grassland habitat will be aided by the CRP. Still, as noted above, the CRP may substantially incrcasc populations of thcsc species and may forestall extinction for somc spccies.

In tcnns of incrcasing the population of spccics there is evidence, as rcvicwcd carlicr, that the CRP incrcases the population of some song and game birds. In thc long tcrm, because thc CRP can increase population sizes, it could help prcvcnt many species from becoming endangered or threatened. The CRP alrcady provides habitat for species that have suffered significani population dcclincs during thc past few decades. Waterfowl such as mallard (Anus plulyrhunchos), northern pintail (Anus acutu), and blue-wingcd teal (Anus discors) havc dcclined by 37, 54, and 28 percent between 1970 and 1985 (U.S. Fish and Wildlifc Service 1986). Some grassland-dependent migratory species such as the lark bunting (Culumospizu melunocorys) and grasshoppcr sparrow (Ammodrumw suvunnurum) declincd by more than four percent per year from 1966 to 1990 (U.S. Fish and Wildlife Service 1990). Continued conversion of pcrcnnial grassland to agricultural land combined with more intensive farming is a suspcctcd cause for the heavy decline in population levels of these species (Johnson and Schwartz 1993b; Kantrud 1993; Rcynolds et al. 1994). The resulting loss of suitable grassland-nesting habitat and habitat fragmentation conccntratc thcsc spccics and their predators in the remaining areas of available

Tabl

e 1.

CR

P E

nrol

lmen

t by

Sta

te

Num

ber o

f A

cres

S

tate

C

on tra

cts

Enr

olle

d

Ala

bam

a 10

,113

57

3,19

0 A

lask

a 40

25

,348

A

rizon

a 0

0

Ark

ansa

s 3,

418

260,

006

Cal

iforn

ia

51 1

187,

499

Col

orad

o 6,

207

1,97

8,39

0 C

onne

ctic

ut

1 10

D

elaw

are

30

995

Flor

ida

2,49

7 13

4.86

0 G

eorg

ia

14,7

18

706,

459

Haw

aii

1 85

Id

aho

3,90

7 87

7,05

9 Ill

inoi

s 19

,685

81

1,9

26

Indi

ana

11,5

39

462.

649

Iow

a 35

,667

2,

224,

834

Kan

sas

31,0

20

2,93

7,86

3 K

entu

cky

8,10

2 45

1,31

7 Lo

uisi

ana

1,78

5 14

6,57

1 M

aine

94

1 38

,490

M

aryl

and

70 7

20

,392

M

assa

chus

etts

5

32

Mic

higa

n 8,

039

332,

853

Min

neso

ta

27,2

24

1,92

8,95

4 M

issi

ssip

pi

13,5

67

841,

826

Mis

sour

i 22

,804

1,

726,

835

Mon

tana

7,

925

2,85

4,30

7 N

ebra

ska

14,4

49

1,42

5,42

3 N

evad

a 10

3,

123

Num

ber o

f A

cres

S

tate

C

on tr

acts

E

nrol

led

New

Ham

pshi

re

0 0

New

Jer

sey

30

723

New

Mex

ico

1,51

8 48

3,18

1 N

ew Y

ork

1,72

9 64

,498

N

orth

Car

olin

a 6,

497

151.

008

Nor

th D

akot

a 18

,520

3,

180,

569

Ohi

o 8,

542

377,

089

0

0

Z

Okl

ahom

a 8.

688

1,19

2,50

4 O

rego

n 2,

012

530,

766

v,

Pen

nsyl

vani

a 2,

649

101,

078

rn

a

<

Pue

rto R

ico

8 45

5 R

hode

Isla

nd

0 0

>

Sou

th C

arol

ina

6,73

7 27

8,07

1

z

Sou

th D

akot

a 12

,476

2,

120,

255

a

Tenn

esse

e 10

,830

47

5,62

5 Te

xas

19,7

62

4,15

0,48

5 rn

cn

rn

Uta

h 99

7 23

3,97

8 V

erm

ont

10

193

a

<

rn

Virg

inia

3,

186

79,5

56

-0

Was

hing

ton

4,48

3 1,

047,

029

Wes

t Virg

inia

35

61

8 a

Wis

cons

in

20,7

69

746,

530

0

Wyo

min

g 79

5 25

7,22

4 >

z

Uni

ted

Sta

tes

Tota

l 37

5,20

5 36

,422

,733

Sou

rce:

Eco

nom

ic R

esea

rch

Ser

vice

, US

DA

. RTD

U

pdat

es: C

onse

rvat

ion

Res

erve

Pro

gram

, Jan

. 19

94, 2

.

s % w 2




habitat. Thc CRP has the potcntial to help revcrsc the heavy dccline of thcse spccics.

A number of sources havc notcd thc gcncral nced to improve the targeting of CRP contracts (e.g.. Heimlich and Osborn 1993). Criteria for geographic targeting takes on added importancc as the CRP faces potential downsizing under the ongoing 1995 Farm Bill debate. Attcmpts to initiate environmental targeting havc begun. As noted carlicr, following thc FACTA of 1990, CRP enrollment and bid acceptance proccdurcs havc bccn revised. Heimlich and Osborn (1993) state that this refocusing “dcmonsuatcs that reducing soil erosion per se, is now less important than broadcr cnvironmcntal goals, such as improving water quality or wildlife habitat.” tlowcvcr, wildlife bcncfits, while often treated as a beneficial by-product or thc CRP have not bcen used cxtcnsively as a criterion for selecting which acrcs to enroll, and the potential for using wildlife benefits as a means of targeting thc CRP is rclalively undcr-investigated (McKenzic and Riley 1995; Miller and Bromcly 1989).

To inotivate the idca of improvement of environmental targeting of the CRP as contracts expire, a brief example is provided using soil erosion data, for which information is readily available. Consider evidcncc of soil erosion rcduction in four slatcs (Kentucky, New Mexico, North Dakota, and Oregon). The states differ dramatically in terms of climate, types of agricultural production, and in tcrms of thc ratio of private to public land. Table 2 lists soil crosion and CRP program information for cach state.

Thcrc are a number of points that can be drawn from examining the comparisons prcscntcd in Table 2. First, CRP acreage and enrollments have bccn hcavily concentrated in midwestern states, as evidenced by the example of North Dakota, which ranks second overall in thc U.S. with over 3 million acres cnmllcd. Yct, thc roughly half million acres enrolled in each of the other states, whilc bclow the national average, is clearly not an inconsequential or trivial amount of land.

Sccond, thcrc is grcat variability in the avcragc acreage per contract. For cxamplc, New Mexico (318.3) hm nearly six times the acrcagc pcr contract of Kcntucky (55.7). This has implications for state and regional planning efforts, cspccially concerning wildlife benefits that may need large patches of unbroken habitat. Transaction costs for assembling large habitat conservation plans may increasc with dccrcasing enrollment size per contract.

Third, there is also considerablc variability across states in thc average cost pcr ton of erosion reduction. The average cost per ton of erosion reduction in Orcgon ($4.46) is roughly five times that of New Mexico ($0.90). Kentucky ($1.80) is wcll bclow the national avcrage and yet twice that of New Mexico.

Targeting the CHP and biodiversify conservation.

Tabl

e 2.

C

RP

Par

amet

ers

in F

our

Sta

tes

~ _

__

__

__

__

__

~

Ren

tal R

ate

Ero

sion

A

vera

ge C

ost

Num

ber

Tota

l A

vera

ge

(dol

lars

per

acr

e R

educ

tion

(dol

lars

per

ton)

or

CR

P

Acre

s A

cres

per

pe

r yea

r, (to

ns p

er a

cre

Ero

sion

S

tate

C

ontra

cts

Enr

olle

d C

ontra

ct

wei

ghte

d pe

r yea

r, R

educ

tion

aver

age)

w

eigh

ted

aver

age)

Ken

tuck

y 8,

102

451,

317

55.7

59

.31

33

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North Dakota ($2.74), with its huge enrollment of acreage, is slightly above the nalional average. Assuming marginal cost of the program is related lo average cosl in some systcmatic way, thcrc arc significant opportunities for rcdirecting contracts away from high-cost areas and towards low-cost areas yielding more soil erosion bcncfits for the same or less cxpenditurc.

Thc cxamplc on soil erosion demonstrates the potcntial for targeting the CRP to incrcasc cnvironincntal benefits. While considcrablc latitude exists for increasing biodiversity, targeting the CRP for this purposc may be difficult for several rcasons. The cffccts of the CRP on species diversity or on wildlife populations may not be as easy to demonstrate as they are for soil erosion.

How to larget the CRP for wildlife benefits dcpcnds in part on what type of benefits arc dcsircd. There are at least two differcnt types of wildlife benefits that could bc goals in targeting CRP land: a) lowering the risk of extinction for thrcatened or cndangcrcd species (or ones that may become threatened or endangcrcd in the futurc); and b) increasing populations of game species, or other valuable species. Spccics diversity requircs information about specics invcntorics by xu. In 1hc following section we use this type of information lo do a preliminary analysis of retargeting the CRP in Oregon.

To date, more attcntion has been given to the increased population of gamc species and the attendant increase in the value of recrcational hunting. Showing the effect of thc CRP on wildlife populations may be difficult however. Economic or management variables rarely have bcen integrated in population biology modcls (Matulich and Adams 1987), though examples of bioeconomic modcls appropriatc to the issues considered hcre do cxist (e.g., Conrad and Salas (1 993); Hammack and Brown (1974); Matulich and Hanson (1 986); Montgomery ct al. (1994); and Williams and Nichols (1990)). More fundarncntally, wildlife populations arc affected by many factors, of which change in CRP status is only one. Population size in a given year may changc because of weather conditions or changes in number of predator or prey populations. Even without any managcmcnt changcs, populalion sizes exhibit oscillations (e.g., Botkin 1990). Certain species may only recovcr with a significant timc lag. Finally, time series of population size do not exist for many species. In ordcr to implement population modcls, the following information would be needed: 1) size and distribution o l habilat parcels, 2) condition and suilabilily of these parcels for mgct spccics, and 3 ) how changes in economic variables changc the size, distribution, condition, o r suitability of parccls. This type of information is rarely available.

Consideration of wildlife benefits may require changes in what typcs of land arc considered for thc CRP program. Ccrlain parcels, notably those containing wetlands or thosc adjoining existing wildlife prescrves or other protected areas,


may be o f high value for generating wildlife benefits. Using a population model for mallards, Rcynolds ct al. (1994) showed that in North Dakota shifting 25 to 30 percent of CRP acrcage from areas of relatively low waterfowl productivity to areas with higher productivity would increase waterfowl production by 26 pcrccnt abovc current Icvcls, while saving $6.1 million annually. Many farmers have cnrollcd small parccls of land surrounded by lands kcpt in crop production. Even though siiiall fields offer suitable habitat to certain types of wildlife, such as song sparrows, other wildlife spccics may nccd large blocks of undisturbcd cover. In order to create largc blocks of protected land, there will nccd to be bcttcr coordination within the CRP, and bctwccn the CRP and other govcmmcnt and privatc wildlifc programs.

Considcration of wildlife benefits may also rcquire changes in vegetative cover and activity on CRP land. The vegetation on most CRP lands consists of introctuccd grasscs and Icgumcs. Consideration of alternative vegetative covcrs could provide incrcascd wildlifc benefits. In addition, the managcmcnt of CRP lands after planting may affcct wildlife populations. Native grassland habitats evolvcd under periodic disturbanccs. Ccrtain managcmcnt practices such as burning, controllcd grazing, or mowing could mimic these events and have a positivc effect on wildlifc productivity (Schenck and Williamson 1991).

An Application of Targeting: The CRP and Species Conservation in Oregon

This scction dcscribcs a preliminary analysis of targeting the CRP to increase thc cffccts of the program on spccics conservation in Oregon. Thc cxtcnt to which currently enrolled CRP land contributes to spccics conservation is examined as well as thc question of whether a differcnt CRP land configuration might be bcttcr suitcd for spccics conscrvation purposes.

Thc analysis hcrc is only preliminary and suggcstivc, not conclusive, for several reasons. First, the data used are rcporlcd by county. Counties in Oregon tcnd to be large, much larger than the areas typically considered for conservation actions. Arcas of high priority may be obscurcd bccause they are aggregated with low priority arcas in countics. Sccond, all spccics arc given equal weight in the analysis (i.e., spccics richness is the objective). If one had information about the differcnt rclative values of different specics a weighted spccics diversity mcasurc could bc used instead of spccics richness (c.g., Solow el al. 199.3). Third, the mcasurc of the conscrvation valuc of an arca is bcttcr captured by the degree to which thc spccics in thc arca arc complementary to other areas rather than by spccics richness (Prcsscy et al. 1993). Conserving multiple arcas each of which contains virtually the same list of spccics may be o f less imporkincc than conscrving arcas with a high proportion of cndcmic spccics even


though the latter arcas may have fewer total species. The current analysis does not take account of the degree of complementarity among areas. A related p i n t is that spccics endcmic to Oregon are more valuable to conserve in Oregon than arc spccics common outside Oregon. With information about the degree of global rarity, such as recorded by the Nature Conservancy’s Natural Hcritagc Program, the weights accorded to species could be adjusted to take account of such di ffcrcnccs.

Thc rccords of thc location of all lands enrolled in the CRP is kcpt by the Economic Rcscarch Scrvice of the USDA. The Biodiversity Research Consortium (BRC) and the Oregon Gap Analysis Program recently completed collccting data on the probable ranges for all vertebrate (and some invertcbrate and plant) spccics in thc state (Kiester et al. 1993). The location of all thrcalcncd and endangered species in thc state has bcen supplied by the Nature Conscrvancy ’s Natural Hcritagc Program. The Orcgon Dcpartment of Fish and Wildlil‘c has uscd thcse sources and its own field work to collect information about charactcristics and habitat needs for various species in the Oregon Species lnvcntory Syslcm (OSIS).

In OSIS thcrc arc 820 spccies of which 401 dwcll in agricultural landscapes. In Orcgon, thcrc are currently 30 spccies on thc federal threatcncd or endangered species list (U.S. Fish and Wildlife Scrvice 1994). Of the endangered or threatcncd species a fcw occupy agricultural lands, among which is thc Columbian sharp-tailcd grouse (Tympunuchus phasianellus columbiunus). This subspccics was belicvcd to be extirpated from thc state but has reccntly becn obscrvcd on CRP ficlds by Fish and Wildlife Service biologists. Further, therc are 225 spccics that arc candidates for listing, which is the sixth highest state toul. The Orcgon Dcpartmcnt of Fish and Wildlife maintains a list of “sensitive spccics,” which is dcfincd as thosc specics likely to bccome endangered or thrcatcned in Orcgon. Among the scnsitive specics are several birds that use CRP lands for foraging and nesting: Swainsson’s hawk (Buteo swuinsuni), ferruginous hawk ( B u m regalis), grasshopper sparrow (Ammodramus savannarum), burrowing owl (Speotyto cuniculariu), loggerhead shrike (Lanius ludovinciunus). A scnsitive mammal observed on Oregon’s CRP lands is thc while-railed jackrabbit (Lepus townsendii).

Thc distribution of CRP lands in Oregon is heavily skewed towards the Columbia Basin. Over 75 pcrccnt of lands enrolled in the CRP in Oregon lie in Wasco, Shcrman, Gilliam, Umatilla, and Morrow Countics (Carlson and Bedell 1991). Howcver, thcse counties rank near the bottom of counties in Orcgon in species richness on agricultural land. In the first column of Table 3, the numbcr of species present in agricultural lands in each county are listed, Umatilla, Morrow, Wawo, Sherman, and Gilliam county rank 21st, 31st. 33rd, 34th, and


36th out of 36 countics. Largcr counties will tend to havc more spccics rcprcscntcd. In thc sccond column of Table 3, the number of spccics pcr farmland acrc, as dcfincd in the 1092 Census of Agriculture, arc listed by county. This mcasurc probably understates the conservation value of lands in countics with largc amounts of agricultural land bccausc the proportionalc incrcase in the number of spccics is not likcly to bc as largc as thc proportionatc incrcasc in arca. Thc fivc Columbia Basin countics, which arc not particularly largc, rank 24th, 30th, 33rd, 34th, and 35th out of 36 countics in tcrms of spccics pcr farmland acrc.

Thcrc is scopc for redirecting the CRP in Oregon towards areas with highcr spccics richncss. For cxample, Klamath County contains 356 specics, which is thc highcsl total for any county in the state (tied with Lane County). Klamath County is homc to thc Uppcr Klamath and Klamath Forest National Wildlife Rcfugcs and contains over 700,000 acres of farmland. Gcncrally, spccics richncss is highcr in thc more humid area west of, or flanking, the Cascade Mountains. Countics listcd in Northwest and Southwcst Oregon gencrally havc grcatcr nuinbcrs of spccies and more spccics per farmland acrc than thosc countics in thc rclativcly dry Columbia Basin and countics in thc rcst or Eastcrn

Arcas o f high priority for targeting the CRP, howcver, should be those arcas whcrc rhc cffcct of a dollar spent in the program is grcat, which arc not ncccssarily arcas that arc spccics rich. To retargct thc CRP to conserve spwics in an cfl'icicnt tnanncr requires information about thc cost of including various units of land in thc C'RP as well as information about the location of spccics. In gcncral, thc paytncnt ncccssary to enroll acres in the CRP will dcpcnd on the valuc of thc land. Column 3 of Table 3 lisrs the average market valuc of an acrc of agricultural land by county. In the last column of Table 3 , thc avcrage value pcr acrc dividcd by thc number of spccies per acre arc listed to gct a sense of thc dollar amount spcnt pcr species. The lop four counties in terms of whcrc conscrvation money would go the furthest, i.c., having the lowcst dollars per spccics mcasurc, arc Clatsop, Lincoln, Curry, and Tillamook, all or which arc locatcd on thc coast. Thc Columbia Basin countics (Sherman, Gilliam, Morrow, Wasco, Umatilla) rank lOth, 1 lth, 28th, 29th, and 33rd. Sherman and Gilliam, evcn though thcy arc relatively specics poor, are ranked rclativcly high bccausc thcy havc vcry low average land values. Viewcd in this way, thc targcting of the current program for conserving species may be more approprim than it appears at first.

Orcgon.


Table 3. Number of Oregon Wildlife Species per Farmland Acre and Estimated

Region Number Number of Estimated Market Dollars

Market Value of Land by Counties

of Species per Value of (000's) County Species farmland acre Land (per acre) per Species

North west Benton Clackamas Clatsop Columbia Hood River Lincoln Linn Marion Multnomah Polk Tillamook Washington Yamhill

South west coos Curry Douglas Jackson Josephine Klamath Lane

Columbia Basin Gilliam Morrow Sherman Umatilla Wasco

Northeast Baker Grant Union Wallowa

331 269 300 289 267 293 307 296 329 298 303 2 95 259

321 31 4 341 339 279 356 356

209 253 222 292 228

290 285 30 1 287

0.0028 0,001 8 0.012 0.0040 0.0098 0.0085 0.00080 0.00098 0.01 1 0.001 8 0.0077 0.0021 0.0014

0.001 8 0.0042 0.00085 0.0013 0.0089 0.00049 0.0015

0.00027 0.00023 0.00046 0.00020 0.00020

0.00035 0.00025 0.00064 0.00041

1,829 5,302 2,307 1,769 6,830 1,842 1,748 3,099 4,227 1,903 2,990 4,606 2,749

1,237 1,380 1,153 1,809 4,141

676 2,051

173 337 283 483 355

38 1 21 6 501 350

653 2,946

192 442 697 21 7

2,185 3,162

384 1,057

388 2,193 1,964

687 329

1,356 1,392

465 1,380 1,367

641 1,465

61 5 2,415 1,775

1,089 864 783 854


Table 3. (continued)

Region Number Number of Estimated Market Dollars of Species per Value of (000’s)

County Species farmland acre Land (per acre) per Species

East Crook 286 0.00032 246 769 Dechutes 323 0.0023 1,670 726

Jefferson 296 0.00056 34 1 609 Lake 325 0.00039 299 767 Malheur 230 0.0001 7 460 2,706 Wheeler 220 0.00030 185 61 7

Harney 330 0.00023 253 1,100

Source: Oregon Species Information System (OSIS), Oregon Department of Fish and Wildlife, 1994; and US. Department of Commerce. Bureau of the Census. 1992 Census of Agriculture. Oregon State and County Data, 1993.

Conclusions Proactivc approachcs to biodivcrsity prcscrvation offcr an avcnuc for

avoiding thc high costs of cndangcrcd-spccies “train wrecks.” Such approaches rcquirc coordinatcd govcrnmcnt policy and inccntivc-based programs for private land-use dccisions. With current cnrollmcnt of ovcr 36 million acres, represcnt- ing ovcr cight pcrccnt of all U.S. cropland, thc CRP reprcscnts an important opportunity for protccting wildlifc and for providing other cnvironmcnhl bcncfits. Thc currcnt probpm has cvolvcd from a focus on prcvcnting crosion to includc a broad array of cnvironmcntal bencfits, including providing habitat. Thc cxpcctcd down-sizing of rhc CRP sharpens thc nccd for improvcd targeting of thc program if it is to contiiiuc to provide important cnvironmcnhl bcncfits.

I n this paper, potcntial opportunities for targcting future CRP cnrollmcnls to conscrvc biological divcrsity havc bccn idcntificd. A preliminary analysis using dala from Orcgon shows there may be considcrablc scope for rctargeting the program to incrcasc biodiversity conservation bcncfits. Implementing changes m a y not bc casy bccausc the program is trying to achicve multiplc goals. Further, ihc primary agcncics involvcd in thc managcment and monitoring of the CRP (thc USDA and thc Soil Conscrvation Scrvicc) do not havc a traditional wilillilc-oricntcd mission, and spccics preservation and habitat protcction considcrrrtion havc bccn rclativcly undcr-invcstigatcd.


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Documents

Conserving Biological Diversity and the Conservation Reserve Program