The California Condor Recovery

The California Condor Recovery

Chancellor,R. D. & B.-U.Meyburg eds. 2000 Raptorsat Risk WWGBP/Hancock House The CaliforniaCondor Recovery T\rrogtamme Lloyd Kiff ABSTRACT Relativelywidespread over North America through the latePleistocene, the Catifomia Condor hasbeen a rare bird throughoutits recordedhistory. Despitemuch habitat preservation,research, education,and enforcement measures, it steadilydeclined in numbersfor nearly200 ycars, reaching a low point of 2l-22 birds in 1983.Losses were due almostentirely to direci humanpersecution, primarily shootingand indirectanthropogenic causes, including lead and possibly other forms of poisoning. "hands-on" In 1980a managementprogftrmme was initiated uy ttreuniteo StatesFish andWildlife Serviceand the NationalAudubon Society. Wild birds weretquippedwith radios!o determine causesof mortality and to identify critical habitat,breeding behaviour was studied intensively, andseveral eggs, young, and adults were taken to zoosto "stablisha captivebreeding programme' Despiteefforts to sustainthe wild population,the speciessuffered a disastrousdecline in the winter of 1984-85to only oneknown breedingpair, and authorities decided to trap the last free-flying individuals for their own securityano to aad them to the captive breedingprogramme. The last free-flyingindividual was broughtinto captivityon 19 April 1987.The first successful captive breedingwas accomplishedin 1988,and pioduciiviryof the captiveflock has inqeased annually sincethen at breedingfacilities at the SanDiego Wild Animal park, Los AngelesZoo, and World CenterforBirds of hey. Thefirst releasesof captiveprogeny occumdin 1992.Subsequently, 16releases have been conducted at four sitesin Califomiaandtwo in Arizona.By theena of tSSi there were 147condors in existence,including 42 n the wild (22 in Arizonaand 20 in California) and 105in captivity.As a resultof theaggressive management programme, the total condorpopulation has increasedby seventimes since the early 1980s,and th; is increasinghope that this unusual speciescan be savedfrom extinction. INTRODUCTION The California CondotGyrwtogyps californianushas always been rare in modemtimes. Judging from fossilevidence, it wasmore common and widespread in thepleistocene, ranging east*.ra al the way to Florida(Brodkorb 1964) nd New York (Steadman& Miller t987), buiby historical timesit occurredonly alongthe Pacific Coast from British Columbia south to northernBaja Califomia (Koford Norte,Mexico 1953).Following the arival of Europeanman on the pacific Coastabout years 200 ago,condor numbers and range declined even more precipitously, almost entirely because 3U of anthropogenicfactors. As recentlyas the 1970s,many writersbegan predicting the Catifornia Condor'scertain and imminent demise. However, an aggressivemanagement programme begun in 1980may yet save it. Knowledgegained from both the positive and negative aspects of theprogramme mightbe usefulto personsatrempting to saveother problem species-. BACKGROUND Early history of condor rrsearrchand management The first detailedsnrdy of the CaliforniaCondor of any kind was conductedby the wildlife photographenWilliam Finleyand Herman Bohlman at EatonCanyon, Los Angeles Counry, Califomia in the springof 1906.The four-panaccount of their exploitsat a condorneit andthe behaviourof the nestling,which they took into captivity,still makesfascinating reading (Finley 1906,l90ga 1908b,19l0). Therewas linle formalattention paid to thespecies until threedecades later when Cyril S. Robinson, a British-bomemployee of the U.S. ForestService, made a pioneeringfield studyof the roosting andfeeding habits of condorsin theLos PadresNational Forest, mostiy in SantaBarbara Counti Califomiabetween 193640 (Robinson 1940). The fint actualgovemmental land management action on behalfof the condorwas the establishmentof the 1,198-acreSisquoc Condor Sanctuary by the U.S.Forest Service in 1937at theurging of localrancher-conservationist Robert E. Eastonand the NationalAudubon Society (Koford 1953).The sanctuaryarea included an importantcondor roost, nestsites, and bathing pool. In a ssnse,the condor management era began with thisevent, since the sanctuarywas henceforth closed to public entrywithout permit. At aboutthe same time, a prominentamateur omithologist and wildlife film pasaden4 "Bill" makerfrcm Califomia,J.R' Pemberton,began effons to film condorsin theSespe area of VenturaCounty, California"He intercstedJohn Baker, president of theNational Audubon Society, and Joscph Grinneit, a professorat the Universityof Califomiaat Berkeleyand the leadingomithologist in rhestate, in theidea ofsupporting a graduatestudent to conducta comprehensivestudy ofthe CaliforniaCondor underGrinnell's direction. With financialsupport from Pemberton and the National Audubon Society, thanksto Baker'sefforts, Carl Koford wasassigned by Grinnellto rheproject, and he conducteda landmarkstudy of thespecies and its breedingbehaviour between 1939-46 (Koford 1953).Koford workedmainly in the backcountry of VenturaCounty, and his findingsled to theestablishment of the35,00G'acre Sespe Condor Sanctuary, which was enlarged to 53,000acres in l95l (Wilbur I97g). In his I 953monograph, Koford (op cit.) estimatedthat the total condor popularion consisted of only 60 individuals,although he privately admittedthat this was a conservativefigure and that the populationmight contain as many as 100birds (Koford in liu.). Condornumbers continued to decline,however, and the National Audubon Sociery commissioned a short-termassessment of thestatus of thepopulation in 1963-64by two Califomiaconservationist ranchers,Ian and Eben McMillan. Their findings, which were published with thecollaboration of Alden H. Miller of the Universityof California Berkeley(Miller er al. 1964),suggesred that the condorpopulation had declined to 40 birds. In 1965'Fred C. Sibleybecame the first U.S. Fish and Wildlife Service biologist charged with studyingthe condor population with thespecific assignmenr of predictingthe effects of a proposed damon Sespecreek, which flows throughthe sespecondor Sancruary,on rhespecies. Also in 1965,the National Audubon Society hired John Borneman as a "condorwarden," armed only with a strongsense of publicrelations and a frnelydeveloped sense of humour.The U.S. Forest Servicesoon had its owncondor biologist, Dean Carrier, and his assignmentwas to preparea condor managementplan for thevast Los PadresNational Forest, which, by then,comprised a largeportion of thecondor's range (Canier 197 I ). Canier'sposition was mainrained between l96g to 1973. Sibley'sassignment lasted for four years,and his conclusionthat thedam would likely havea disastrousimpact on thecondor population (Sibley 1969) coincided with thedefeat of theproject by the localelectorare. During his tenure,Sibley, Robert D. Mallette(california Departmentof Fish 308 andGame), and Borneman, initiated an annualsurvey of thecondor population, which washeld for two dayseach October from 1966to 1980and involved the participation of 50-100 trained observers (Mallette& Bomeman1966). The combined results of severalsurveys indicated that the total condor populationwas between50-60 individualsbetween 1966-70 (Wilbur 1978)and confirmedwhat manyhad suspected,i.e., that the populationestimate of the McMillans (Miller et at. 1964)was probablytoo conservative. SanfordR. Wilbur followedSibley as the U.S. Fish and Wildlife Servicecondor biologist in late 1969,and he held that position until 1980.During this entire period, he wasthe only U.S. Fish and "prograrnme." Wildlife Serviceemployee assigned to the condor Wilbur produceda monographic accounton the species,including an exhaustivebibliography (Wilbur 1978),and madedetailed studieson condorfood resources(IVilbur 1972),plumages (Wilbur 1975),and populationstatus (Wifbur et al. 1'972,1976). He alsocollaborated in a studyof DDE-inducedeggshell thinning in condors(Kiff er al. 1979),conducted supplemental feeding experiments near the SespeCondor Sanctuary(Wilbur et al. 1974),and madeseveral expeditions to the Sierra San PedroMarth Baja CaliforniaNorte, Mexico in a fruitlessattempt to confirm the existenceof condorsin that range (Wilbur & Kitr 1980).Finally, he organizedthe First InternationalSymposium on theVultures, co- sponsoredby the WestemFoundation of VertebrateZoology andheld at the SantaBarbara Museum of NaturalHistory in 1979.The proceedingsappeared as a major book on Old and New World vulturebiology and conservation (Wilbur & Jackson1983), and the symposiumgrearly facilitated collaborationbetween vulture researchers on severalcontinents. As a partof theFederal mandate to recovercondor populations, a "CalifomiaCondor Recovery Team" was establishedin 1972.Consisting of five members,representing the four govemment agenciescooperating in the programme,plus the NationalAudubon Society,the Tlnm preparcda rrecoveryplan for thespecies (U.S. Fish andWldlife Service1974).ltwas formalized in 1975,the first of its kind everapproved by theU.S. Fish and Wildtife Service.The plan washeavily oriented towardprotecting condor habitat as a meansof savingthe species. Habitatprotection, nest protection, and enforcement had been the themes of condorrecovery for manyyears, yet the Fendsin theannual survey results and the completedisappearance of condors from areaswhere they hadoccuned regularly up until very recentyears indicated that the species wascontinuing to decline.By thelate 1970s, Wilbur (1978) estimated thar the total condor population consistedof no morethan 50, andpossibly as few as40, individuals.By now,even some biologists werepredicting

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