Prospects for Recovering Endemic
Fishes Pursuant to the U.S. Endangered
Downloaded by [Oregon State University] at 14:25 29 November 2011
Species Act
If the successof the Endangered SpeciesAct (ESA) is measured by the number of
endangered speciesthat have been recoveredand dellsted, then the act is not very
successful.
Only 15 specieshave been dellsted becauseof recoveryin the historyof
the ESA.The Borax Lake chub (Gila boraxobius), an endangered speciesrestrictedto
an Oregon spring system,is consideredto be on the brink of recoveryand may warrant future dellsting. A panel of scientistswas convened to determine consensus
regarding the species'listing status by reviewing: (1) current habitat conditions, (2)
implementation of the recovery plan, and (3) applicability of ESA listing factors.
Despite substantial progresstowards recovery,threats to the speciesremain, including habitat degradation and the potential introduction of nonnative species.These
are problems common to many fishes of highly restricted distribution. Becausethe
Borax Lake chub occursin a single spring system,the speciesremains vulnerable to
catastrophiclossand requirescontinuing protection afforded by the ESA.Like many
spring-dwellingfisheswith a restrictedrange, recoveryof the BoraxLake chub to the
point where ESAprotection is no longer required is an admirable but largely unobtainable goal. Prevention of extinction rather than dellsting is a more appropriate
measure of ESAsuccessfor such species.
Jack E. Williams
According to Section 2 of the
EndangeredSpecies Act of 1973
(ESA), the primarypurpose
of the act
of endangered
andthreatenedspecies
until a total
of 1,262 species(517 animals,745 plants)were
Don W. Sada
listed in the United States as of 2003 (U.S. Fish
and Wildlife Service[USFWS] 2004a).
extinctionsand to provide a means
Over thissametimeframe,37 species
havebeen
wherebythe ecosystems
upon which delistedandsubsequently
removedfromESA proendangeredand threatened species tection. Of these, 15 were delisted because of
dependmay be conserved.The ESA recovery,7 becauseof extinction,and 15 because
Jack Williams is chief scientist for
tant conservation law in the United
Catherine
A. Macdonald
Cindy Deacon Williams
Hal Weeks
Georgina Lampman
TroutUnlimitedin Ashland,Oregon.
He can be reached at
jwilliams@tu.org.
Macdonaldisthe
vicepresidentfor stewardship
at
The NatureConservancy
in Portland,
Oregon.Williamsisa fishery
consultantin Medford,Oregon.
Weeksisa projectleaderwith the
OregonDepartmentof Fishand
Wildlifein Newport,Oregon.
is to stem the tide of human-caused
is widelyregarded
asthe mostimpor- of new informationor taxonomicrevisionshowing
their listingwasin error(USFWS 2004b).The low
is duelargelyto inadStatesand is viewedas the pinnacle numberof recoveredspecies
of legislationfor protectingwildlife equateprotectionfroma growingarrayof threats
(Bean 1983; Plater 2004). Becauseof to speciesand habitats,and becausedelisting
its importance and influence, the removesthe primaryregulatoryprotectionavailESA has been the keystone for a
growingnumberof conservation
bat-
able--that is, from the ESA itself (Doremus and
Pagel 2001). Indeed, somescientistsand legal
havequestioned
whetherwe arelikelyto
tles acrossthe country. Conflicts scholars
andinstead
betweenapplicationof the ESA and seethe recoveryof manylistedspecies,
that recoveryshouldbe viewedas
land and waterdevelopment
projects have proposed
have increased because of several facan aspirational
goalratherthana realisticexpectaLampmanis the Intermountain
tion
for
many
listed species(Doremus 2000;
tors, but chief among these is the
Regionaquaticecologyleadfor the
Doremus
and
Pagel
2001). On the other hand,
U.S. ForestServicein Ogden,Utah.
cumulative effects of a growing
Sadais an aquaticecologistwith
human population and increasing others have encourageddelistingsbecauseof
the Desert Research Institute in
resourcedemand coupled with an recoveryfor a varietyof practical,political,and
Reno, Nevada.
reasons
(Benderet al. 1998).
increasingnumberof specieslistedas philosophical
The growing list of protected speciesand
endangered
or threatened.
The 30-yearhistoryof the ESA hasbeenchar- increasing human-causedfragmentation and
of naturalhabitatspresents
a looming
acterizedby a growinglist of protectedspecies, degradation
for conservation
efforts.As conflicts
subspecies,and distinct population segments conflagration
(hereinafter"species").
When the ESA wassigned escalatebetweenthe ESA and human developinto law by PresidentNixon in 1973, 119 species ment, there are growingefforts to reduce the
received"grandfathered"
protectionfromthe ear- impactand effectiveness
of the ESA. One wayto
lier EndangeredSpeciesConservationAct of reducethe impact of the ESA is to reducethe
1969. From 1973 through 2002, an averageof numberof protectedspecies,
eitherby slowingthe
neady43 species
wereaddedeachyearto the list numberof new specieslistingsand/orincreasing
24
Fisheries I www.fisheries.org I vol 30 no 6
the numberof delistings.
Forthe first20 yearsfol- Case Study:
lowingpassage
of the ESA, there were only 18 The Borax Lake
delistings,
but since1993the rateof delistings
has
increased. Elements on both sides of the conserva-
The
Borax
Lake
Chub
chub
is endemic
to the
Downloaded by [Oregon State University] at 14:25 29 November 2011
geothermally-heatedwaters of Borax Lake and
adjacent wetlands in Oregon's Alvord Basin
tion debatehavesoughtto increase
the numberof
delisted species. During the Clinton
Administration, Interior Secretary Babbitt (Williams and Bond 1980). The chub was listed
believedthat the USFWS'sabilityto delistspecies as endangeredin 1980 by emergencyrule and
because
of recoverywasa clearindicationthat the again as endangered by final rule in 1982
ESA was a success.
During this period, USFWS (USFWS 1982). At the time of listings,the priexpediteddelistingefforts,includingdevelopment marythreatsto the species
consisted
of potential
of lists of speciesthat might warrant delisting impacts from geothermal energy development
because
of recovery(Benderet al. 1998).As Rohlf and diversionof the lake'soutflowsby alteration
(2004) pointedout in a recentreviewof Section4
of the shorelinecrusts.Although no recovery
of the ESA, federalagencies
have both political
team ever wasformedfor this species,a recovery
incentive and institutional desire to find successin
plan wascompletedin 1987 that calledfor prothe ESA bypointingto recoveredspecies
that may
be delisted.Of course,thosethat opposethe ESA tection of the Borax Lake ecosystemthrough
are equally glad to see fewer speciesprotected acquisitionof key private lands, protectionof
underthe act'sprovisions,
butfor differentreasons. subsurfaceand surfacewaters,controlson access,
Amongthe species
that mightwarrantcontem- removal of livestock grazing, monitoring, and
porary delistingis the Borax Lake chub (Gi/a other recoveryactions(USFWS 1987).
The BoraxLakechubexistsasa singlepopulaboraxobius),
anendangered
species
inhabiting
a small
tion
that mostlikely hasbeenmaintainedwithin
hot-spring
ecosystem
in southeastern
Oregon.The
restricted
habitatoccupied
bythe species
recently
has its historicrange of natural variability,and an
beenacquired
by a conservation
groupandsurround- increase in abundance is not a factor in successful
ingpubliclandhasreceived
additional
protections.
In recovery.Recovery, in this instance, is based
2003, we conducteda reviewof the conservation
sta- entirelyon habitat integrity,includingprotection
tusof the BoraxLake chubto developa scientific of springaquifers,and the avoidanceof nonnaconsensus
regarding
the listingstatusandfuturecon- tive speciesintroductions.
BoraxLakeisa spring-fed
ecosystemin Oregon's
AlvordDesertand, along
with surroundingpools
and marshes,the sole
habitatfor the endangered
Borax Lake chub.
servation needs of that
species.
The purposes
of
this articleare to report
on the resultsof our evaluation of the Borax Lake
chub,discuss
implications
of ourfindingforthevulnerabilityof otherspecies
of restricted
range,andto
provide recommendations for statusreviews for
endemic specieslisted
pursuant
to theESA.We
also offer our opinion
regarding
appropriate
criteria for measuringthe
successof the ESA itself.
Managementof endangered and threatened
fishes, including their
recovery
anddelisting,
are
criticaltopicsto fisheries
biologists.
We hopethis
article stimulates further
debate on measures of
successfor the ESA and
understanding
of the •
appropriate
role of •
delisting.
::,•
..........
June 2005 I www.fisheries.org I Fisheries
25
Numerousrecoverymeasures
havebeenimplemented during the past two decadesto secure
habitat for the species.In 1983, the Bureauof
Land Management(BLM) designated
the public
lands surroundingBorax Lake as an Area of
Critical
Environmental
Concern.
The
Nature
Conservancy
(TNC) leasedtwo 160-acreprivate
landparcels,onesurrounding
BoraxLakeandthe
otherimmediatelyto the north, in 1983andpurchasedthem outright in 1993, therebybringing
all landsdesignated
ascritical habitat into public
or conservationownership.With the acquisition
by TNC, livestockgrazingceased.Passage
of the
and (4) convening of a 16-memberscientific
panel to reviewfindingsfrom the recoveryplan,
habitat, and listingfactorreviews.The panelists
werescientiststhat had workedpreviouslyon the
speciesand its habitat, agencybiologistswith
managementresponsibility
for the species,and
other scientistswith extensive knowledge of
desertspringsystems
in westernNorth America.
Panelistswere asked,usingtheir best scientific
judgmenton issuesrather than agencypositions,
to developa consensus
on listingstatus,management, and monitoring.
The expert panel concludedthat substantial
progress
hasbeen madetowardsrecoveryof the
Borax Lake chub, but that despitethis progress,
threats to the speciesand ecosystemremain.
Downloaded by [Oregon State University] at 14:25 29 November 2011
SteensMotretain Cooperative Managementand
Protection Act of 2000 withdrew public lands
from mineral and geothermal development
within a majorityof the Alvord Basin,including Results of the status review are summarized in
the Alvord
Table 1. Summaryof status
reviewfindings
for the Borax
Lakechub.Forrecovery
plan
implementation
review,
recovery
subtasks
were
scored on a scale of 0•4.
0 = no implementation
1 = minorimplementation
2 = approximately
half
implemented
3 = mostlyimplemented
4 = fullyimplemented
Known
Geothermal
Resource Area
Table
1. Threats
that
had been
eliminated
and Borax Lake.
included the alteration
With removal of many of the significant
threatsfacingthe BoraxLakechub,the U.S. Fish
and Wildlife Servicebeganto examineits feasibility for reclassification(R. White, USFWS,
pers.comm.).The BoraxLake chubfrequentlyis
citedby USFWS asbeing"on the brink of recovery" (Motivans and Balis-Larsen2003) and is
rated by that agencyas having achieveda relatively
high
percentage of
recovery
implementation (51-75%; USFWS 2003). In
flows, livestockgrazing,and geothermalenergy
development on public lands. The primary
remainingthreatswere increasinghabitat degra-
2003, two of the authors conducted a status
review
of the Borax Lake chub to determine
whethera changein listingstatuswaswarranted
andto reviewfuturemanagementandmonitoring
needsfor the species(Williams and Macdonald
2003). The status review consistedof four com-
ponents: (1) review of recovery plan
implementation,(2) field investigations
at Borax
Lake to determinecurrent statusof the species
and habitat, (3) review of the five listingfactors
from Section 4 of the EndangeredSpeciesAct,
of lake shoreline and out-
dation associated with recreational
use and the
increasingpotential of nonnative speciesintroduction. Exotic goldfish (Carassiusauratus)
recentlyhave been introducedinto Mann Lake
just to the north of Borax Lake (Tim Walters,
Oregon Department of Fish and Wildlife, pers.
comm.). Both recreationand introducedspecies
receivedminor attention in the 1987 recovery
plan. Borax Lake is located in a remote and
sparsely-populated
area,but one that is increasingly usedby a public seekingopportunitiesfor
solitude,wildlife observation,and open space.
The panelbelievedthat becausethe rangeof the
BoraxLake chub is restrictedto singlegeologically fragile site, the speciesis vulnerable to
catastrophic
lossdespiteexistingprotection.The
panelalsonotedthe importanceof frequentmonitoring to detect and move to extirpate
RecoveryPlan Implementation Task1: Securelandand water rights.Averagesubtaskscore= 3.7.
Task2: RestoreLowerBoraxLake,smallponds,and interveningmarshes.Averagesubtaskscore= 4.0.
Task3: ProtectBoraxLakeecosystem.Averagesubtaskscore= 2.7.
Task4: Monitorstatusof ecosystem.
Averagesubtaskscore= 2.3.
Task5: Encouragesupportof recoverythroughpublicawareness.Averagesubtaskscore= 3.5.
Field Investigations
Habitatand chubpopulationappearedin goodconditionandwithinexpectedrangeof variationobserved
historically.
Significantrecreationaluse(off-roadvehicleuse,camping,disturbance
of lakesubstrates
from
wading)was noted.
Review of 5 ListingFactors
1. Presentor threateneddestruction,
modification,
or curtailment
of its habitator range.
1982:threatsconsisted
of chippingof crustsaroundshoreline,diversion
of outflows,
development
of geothermalresource,
and potentialdevelopment
of recreation
facility.
2003: threatsconsistof recreational
useand potentialwater developmenton privatelands.
2. Overutilization
for commercial,
sporting,scientificor educationalpurposes.
1982, 2003: no threats for this factor.
3. Disease
or predation.1982:no threatsfor thisfactor.2003: potentialintroduction
of nonnative
species.
4. Inadequacy
of existingregulations.
1982: no threatsfor thisfactor.2003: no threatsfor thisfactor.
5. Othernaturalor manmadefactorsaffectingitscontinuedexistence.
1982:no threatsfor thisfactor.2003: because
of restricted
range,species
vulnerable
to disturbance
event.
26
Fisheries I www.fisheries.org I vol 30 no 6
Downloaded by [Oregon State University] at 14:25 29 November 2011
introducedspeciesandto be ableto act quicklyin
the face of other new threats.No changein listing statuswasrecommended
althoughthe expert
panelconcludedreclassification
from endangered
to threatenedcould be appropriatein the near
futuredependingprimarilyupon implementation
of a regularmonitoringprogram.The panel further concludedthat "maintainingthe BoraxLake
chub on the list of Endangeredand Threatened
Wildlife and Plantsaffordsthe greatestlikelihood
that sufficientscientificand agencyattentionwill
alligatorandperegrine
falcon.Fivefisheshavebeen
removedfrom the list of threatenedand endangered
species,
fourbecause
of theirextinction(Tecopapupfish [Cyprinodon
nevadensis
calidae],longjawcisco
[Coregonus
alpenae],
bluepike[St/zosted/on
vitreum
glau.
cum],andAmistadgambusia
[Gambusia
amistadensis])
and one becauseof taxonomicrevision(Umpqua
River form of coastalcutthroattrout,Oncorhynchus
clarkiclarki).No fisheshave beendelistedbecause
of
recovery.
Althoughit isdifficultto generalize
aboutthe
characteristics
of listedspecies
that makegoodcandibe focused on Borax Lake such that if habitat
datesforrecovery,
it seems
clearthat species
with the
suiteof characters
maymorereadilyrespond
integrity is compromised,correctiveaction will following
to recovery
efforts:
(1) habitatrequirements
aremore
be timelyenoughto savethe species."
generalthan specific,(2) qualityhabitat remains
Delisting and Vulnerability of
withinhistoricrange,and (3) existingthreatfactors,
Endemic
Fishes
suchasoverharvest,
maybe easilyregulated.
Simply
species
oftenfacedthreatsthat were
Given the plethoraof possiblecausesof popu- stated,recovered
to address
throughavailable
regulatory
channels
lation endangerment,determiningvulnerability easier
of speciesto extinctioneventsis difficult.Many (AbbittandScott2001).On the otherhand,species
habitatsand/orsmaller
ranges
maybe
factorsare relevant, includinga species'habitat fromspecialized
more
vulnerable
to
loss
(Terborgh
1974;
Deacon
and
requirements,
populationsize,and dispersalabiliMinckley
1991).
In
a
review
of
the
conservation
status
ties (Tilman et al. 1994; Driscoll 2004).
Furthermore,a searchfor explanationsof status
changesin many lesser-knownspecieslisted as
endangeredor threatenedoften is hinderedby
our lack of knowledgeof their basiclife history
and habitat requirements.Nonetheless,certain
factorscommonto manyendangeredspeciesare
known to increase the likelihood
of their extinc-
tion. Thesefactorsincludesmallpopulationsize
(SouIt 1983;Gilpin and SouIt 1986), restriction
to a smallgeographic
area(Lovejoyet al. 1986),
dependenceupon a specific rare habitat type
(Terborgh1974), and inability to move away
from increasingsources
of stressor habitat degradation (Diamond 1975).
Endemicfisheswith a highly restrictedrange
are particularlyvulnerableto extinctionbecause
they occuras a singleor low numberof populations, dependupon a specifichabitat type, and
have
low
tolerance
for habitat
modification.
Endemicfishesmay be commonin the limited
areaswherethey occurbut oftenhave rigid habitat requirements. These endemic species
therefore,becomehighly vulnerableto habitat
change or invasion of nonnative species
(Minckley and Deacon 1968; Terborgh 1974).
The vastmajorityof recentU.S. extinctionshave
been in specieswith restrictedranges,including
freshwater musselsof southeastern rivers, and
plants and terrestrialinvertebratesof Hawaiian
forests(Sucklinget al. 2004). In their review of
westernfish conservation,Deaconand Minckley
(1991) concludedthat the restricteddistributions
and small population sizes of many springdwellingfishesdictated their virtual permanent
statusasendangeredor threatened.
Of the 15species
thathavebeendelisted
because
of
recovery,
mostarewide-ranging,
suchastheAmerican
June 2005 I www. fisheries.org I Fisheries
Jackrabbit
Springin Ash
of aquaticspeciesin the Great Basin,Sada and Meadows,Nevada,provides
Vinyard(2002) foundthat dedinesweregreatest
in habitatfor the endangered
the mostnarrowly
distributed
andvulnerable
popula- AshMeadowspupfishand
tions.According
to theiranalysis,
all extincttaxaand AshMeadowsspeckled
osculus
mosttaxasuffering
majordedines(68%) hadfewer dace(RhinichthJ/s
nevadensis).
Othernearby
thanfivesmallpopulations.
springsprovidehabitatfor
A reportby Benderet al. (1998)listed22 species the endangeredDevilsHole
considered
likelycandidates
by USFWSfor delisting pupfish(Cyprinodon
andwarmsprings
or redassification
becauseof increased
protection, diabolis)
pupfish(C nevadensis
includedthreefishes:tidewatergoby(Eucyclogobius
Despite
newberryi),Ash Meadows pupfish (Cyprinodonpectoralis).
designation
of the springs
nevc•lensismionectes),and Pahrump poolfish asprotectedareas(Ash
(Empe•ch•hys
/atos).The tidewatergoby is more Meadows National Wildlife
broadlyranging,but the Ash Meadows
pupfishand Refugeanddisjunctportion
Pahmmppoolfish
arebothspring-dwelling
fishes
with of DeathValleyNational
restricted
rangesthat are similarto the BoraxLake Park),habitatsand fishes
remain vulnerable.
27
Downloaded by [Oregon State University] at 14:25 29 November 2011
in ensuringthe continuedexistence
of
chubin termsof vulnerability.
The AshMeadows
pupfish
andthree ESA hasbeensuccessful
otherlistedfishesareendemicto springs
in the Ash Meadows
area the taxa it protects.
Delisting of spring-dwelling
fisheswith restrictedranges
butremainvulnerable
to catastrophic
lossbecause
ofintroductions
of
with considerable
cautionbecause
of their
nonnative
species
and/ormodification
to subsurface
aquifers.
These shouldbe approached
andbiologicalvulnerabilityandtheir ability
threats
persist
despite
protective
management
of landaround
surface inherentecological
protectingmanylesser-known
and
spring
areas.
Therecovery
planforAshMeadows
species
listsprotec- to serveasumbrellaspecies
Althoughthe BoraxLakechubhasa higher
tionof aquifers,
eradication
of nonnativespecies,
andrestoration
of unlistedorganisms.
than manylistedspecies,
it appears
to an
naturalspring
habitats
asessential
criteriathatmustbemetbefore rateof recoverysuccess
fishesshouldbe considered
for delistingor reclassification
from expertpanelto be a poorcandidate
for delistinglargelybecause
dependenton
endangered
to threatened
(USFWS1990).Recovery
ofthePahmmp of its inherentvulnerabilityasan endemicspecies
poolfish
isdoubtful.
Thisspecies
hasbeeneliminated
fromitssingle a specialized
habitat.Ironically,because
the ESA isa strongregand habitatprotection,removalof this
spring
historic
habitatbutexists
asan introduced
population
onthe ulatorylaw for species
DesertWildlifeRange.Like the BoraxLakechub,thesespring- protectionthroughthedelistingprocess
alsoremoves
thepreemdwelling
desert
fishes
arelikelyto needtheprotection
afforded
bythe inent tool for maintainingthe speciesin the long run. The
naturallyrestrictedrangeof many endemicfishesmakestheir
ESA in perpetuity.
to thepointof delisting
an admirable
butlargelyunobCurrentprocedures
forddistingspecies
pursuant
to Section4 of recovery
goal.•
theESAaresimilarto listing.That is,thestatus
ofthespecies
iscom- tainable
paredtothefivelistingfactors
contained
in Section
4, andfidelisting
is believedwan'anted
by USFWS, a proposal
is published
in the Acknowledgments
Federal
Register
notifying
thepublicoftheproposed
change
andseekThe authorswouldlike to acknowledge
ourfellowBoraxLake
ingpubliccomments.
We suggest
thepanelreviewconducted
forthe
panelists:
Chris
Allen,
Darren
Brumback,
MichaelCummings,
BoraxLakechubmayprovide
a suitable
modelto evaluate
theESA
JosephFurnish,Mary Hanson,Kathy Hollar, Phil Pister,Pete
status
of endemic
species,
particularly
thoselackingrecovery
teams.
Rissler,Dan Salzer,andTim Walters.The authorsalsowouldlike
Forspecies
withrecovery
teams,
theteamlikelycouldsubstitute
for
to acknowledge
JoelE. Pageland two anonymous
reviewersfor
theexpertpanel.Regardless,
a varietyof factors
should
bereviewed their comments on earlier versions of this article. Much of this
in anydelisting
process,
including
the implementation
status
of any
workwascompleted
whilethe seniorauthorwasat the Institute
applicable
recovery
plansandcurrentstatusof subject
populations
for EnvironmentalStudiesat Southern Oregon University.
andhabitats,
in additionto an analysis
of thefivelistingfactors.
Fundingfor the listingstatus
reviewof the BoraxLakechubwas
providedby the U.S. FishandWildlifeService.
Conclusions
References
The desireto delistspeciesis driven,at leastin part, by the
Abbitt,R. J. F., andJ. M. Scott.2001.Examining
differences
between
beliefthat recoveryof listedspecies
isan indicatorof the success
recoveredand decliningendangeredspecies.Conservation
of the ESA. Butwith only 15 taxadellstedbecause
of recoveryin
Biology15(5):1274-1284.
the historyof the ESA, success
asmeasured
by thisindicatoris Bean, M. J. 1983. The evolutionof nationalwildlifelaw (revised
poor.Moreappropriate
indicators
wouldincludechanges
in popandexpanded
edition).Pmeger
Publishers,
NewYork.
ulationtrendsof listedspecies
andthe abilityof ESAprotections Bender,M., K. Day Boylan,and E. L. Smith.1998.Turningthe
cornertowards
recovery.
Endangered
Species
Bulletin23(2-3):4to preventextinction.In itslatestbiennialreportto Congress
on
9.
recoveryof listedspecies,
USFWS (2003) reportedthat population trendsfor39% of listedtaxawereeitherstableor increasing, Deacon,J. E., andW. L. Minckley.1991.Westernfishesandthe
real world:the enigmaof "endangered
species"
revisited.
Pages
while 34% weredeclining,and 24% wereuncertain.Pursuantto
405-413in W. L. MinckleyandJ. E. Deacon,eds.Battleagainst
this indicator,the ESA faresbetter. If preventingextinction is
the criterion, an assessment
of the success
of the ESA is even
extinction: native fish managementin the American West.
Universityof ArizonaPress,
Tucson.
morepositive,with only 7 taxadellstedbecause
of extinction. Diamond, J. M. 1975. The islanddilemma:lessonsof modern
biGgeographical
studiesfor the designof naturalpreserves.
Biological
Conservation
7:129-146.
Doremus,
H.
2000.
Delisting
endangered
species:
an aspirational
and 1998 (Schwartz1999). Recent data from the Center for
goal, not a realisticexpectation.The Environmental
Law
BiologicalDiversity(Sucklinget al. 2004) supports
the valueof
Reporter30:10434-10454.
ESA protectionsin preventingextinction.An analysisof 114 Doremus,H., andJ. E. Pagel.2001.Why listingmaybe forever:
extinctionsof U.S. speciessincethe ESA waspassedin 1973
perspectives
ondellsting
undertheU.S. Endangered
Species
Act.
One studyestimated
that basedon riskof extinctionalone,192
listedtaxawouldhavebeenexpected
to goexunctbetween1973
found that 81% of extinction events involved taxa that were not
Conservation
Biology15(5)1258-1268.
protectedby the ESA (19% werelisted).Sucklingand others Driscoll, D. A. 2004. Extinction and outbreaksaccompany
fragmentation
of a reptilecommunity.
Ecological
Applications
(2004) believethatremovalof procedural
delaysin listingspecies
14:220-240.
pursuant
to theESAandeliminationof thelistingbacklog
would
Gilpin,M. E., andM. E. Soul(-'.
1986.Minimumviablepopulations:
haveresultedin increased
protectionthat likelywouldhavepreprocesses
of species
extinction.Pages19-34in M. E. SoulS,ed.
ventedmanyextinctions.
Additionally,manyrarebutnon-listed
Conservation
biology:the scienceof scarcityand diversity.
species
occurwith listedspecies
andmayreceiveprotectionthat
Sinauer.Associates,
Sunderland,
Massachusetts.
couldbe indirectlycreditedto the ESA. Regardless,
the small Lovejoy,T. E., R. O. Bierregaard,Jr., A. B. Rylands,J. R.
Malcolm,(2. E. Quintela,L. H. Harper, K. S. Brown,Jr., A. H.
numberof extinctions
of listedspecies
suggests
stronglythat the
28
Fisheries I www. fisheries.org I vol 30 no 6
Powell, G. V. N. Powell, H. O. R. Schubart,and M. B. Hays. Terborgh,J. 1974.Preservation
of naturaldiversity:the problemof
1986. Edge and other effectsof isolationon Amazon forest
extinctionpronespecies.BioScience24:715-722.
fragments.Pages257-285 in M. E. SoulS, ed. Conservation Tilman, D., R. M. May, C. L. Lehman, and M. A. Nowak. 1994.
biology:the scienceof scarcityanddiversity.SinauerAssociates,
Habitat destruction and the extinction debt. Nature 371:65-66ß
Sunderland,Massachusetts.
USFWS (U.S. Fish and Wildlife Service).1982ßEndangered
and
Minckley,W. L., andJ. E. Deacon.1968.Southwestern
fishesand
threatenedwildlife and plants; endangeredstatusand critical
the enigmaof "endangered
species."
Science159:1424-1433ß
habitatfor BoraxLake chub (Gi/a boraxobius).
FederalRegister
Motivans,K., and M. Balls-Larsen.2003. Specieson the brink of
Downloaded by [Oregon State University] at 14:25 29 November 2011
recovery.Endangered
SpeciesBulletin28(4):10-11.
Plater,Z. J. B. 2004. Endangered
Species
Act lessons
over30 years,
and the legacyof the snaildarter,a smallfish in a porkbarrel.
47 (193):43957-43963ß
1987ßRecoveryplan for the Borax Lake chub, Gi/a
boraxobius.
U.S. FishandWildlifeService,Portland,Oregon.
Environmental Law 34:289-308.
__.
1990. Recoveryplan for the endangered
and threatened
Rohlf, D. J. 2004. Section4 of the Endangered
SpeciesAct: top ten
species
of AshMeadows,
Nevada.UßS.FishandWildlifeService,
issues
for the next thirty years.Environmental
Law34:483-553.
Portland,Oregonß
Sada,D. W., and G. L. Vinyard. 2002.Anthropogenicchangesin
ß2003.Recoveryreportto Congress:
FiscalYears1997-98and
biogeography
of Great Basinaquaticbiota. Pages277-293in R.
1999-2000.U.S. Fishand Wildlife Service,Washington,D.C.
Hersbier,D. B. Madsen, and D. R. Currey, eds. Great Basin
2004a. Number of UßS. specieslistingsper calendaryear.
aquaticsystems
history.Smithsonian
Contributionsto the Earth
Available
onlineat http://endangered.fws.gov/stats/List
cy2002.PDE
Sciences33. SmithsonianInstitutionPress,Washington,DßC.
. 2004b.Threatenedand Endangered
SpeciesSystemdellsted
Schwartz,M. W. 1999.Choosingthe appropriate
scaleof reserves
for conservation.
Annual Reviewof Ecologyand Systematics species report as of 02/02/2004. Available online at
30:83-108.
http://ecos.fws.gov/tess_publicJTESSWebpageDelisted
?listings=0.
SoulS,M. E. 1983ßWhat do we reallyknowaboutextinction?Pages Williams,J. E., andC. E. Bond.1980.Gi/aboraxoNus,
a newspecies
111-124 in C. M. Schonewal&Cox, S. M. Chambers, B.
MacBryde,
andW. L. Thomas,eds.Geneticsandconservation:
a
referencefor managingwild animal and plant populations.
Benjamin/CummingsPublishing Company, Menlo Park,
of cyprinidfish from southeastern
Oregonwith a comparisonto
G. alvordensis
Hubbsand Miller. Proceedings
of the Biological
Societyof Washington93:293-298.
Williams,
J. E., and C. A. Macdonald. 2003. A review of the
California.
conservation
statusof the Borax Lake chub, an endangered
Suckling,K., R. Slack, and B. Nowicki. 2004. Extinctionand the
species.Unpublished report. Southern Oregon University,
Endangered
Species
Act. Centerfor Biological
Diversity,
Tucson,
Arizonaß
June 2005 I vvww.fisheries.org I Fisheries
Ashland.
29