Salinas, CA, United States
Salinas, CA, United States

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Rideout B.A.,Institute for Conservation Research | Stalis I.,Institute for Conservation Research | Papendick R.,Institute for Conservation Research | Pessier A.,Institute for Conservation Research | And 16 more authors.
Journal of Wildlife Diseases | Year: 2012

We document causes of death in free-ranging California Condors (Gymnogyps californianus) from the inception of the reintroduction program in 1992 through December 2009 to identify current and historic mortality factors that might interfere with establishment of selfsustaining populations in the wild. A total of 135 deaths occurred from October 1992 (the first postrelease death) through December 2009, from a maximum population-at-risk of 352 birds, for a cumulative crude mortality rate of 38%. A definitive cause of death was determined for 76 of the 98 submitted cases, 70%(53/76) of which were attributed to anthropogenic causes. Trash ingestion was the most important mortality factor in nestlings (proportional mortality rate [PMR] 73%; 8/11), while lead toxicosis was the most important factor in juveniles (PMR 26%; 13/50) and adults (PMR 67%; 10/15). These results demonstrate that the leading causes of death at all California Condor release sites are anthropogenic. The mortality factors thought to be important in the decline of the historic California Condor population, particularly lead poisoning, remain the most important documented mortality factors today. Without effective mitigation, these factors can be expected to have the same effects on the sustainability of the wild populations as they have in the past. © Wildlife Disease Association 2012.


Burnett L.J.,Ventana Wildlife Society | Sorenson K.J.,Ventana Wildlife Society | Brandt J.,U.S. Fish and Wildlife Service | Sandhaus E.A.,Santa Barbara Zoo | And 6 more authors.
Condor | Year: 2013

From 1997 through 2010, in collaboration with the National Park Service, we released 84 captivereared California Condors (Gymnogyps californianus) to the wild in central California; from 2006 through 2010 we recorded 16 nestings by nine pairs and recovered eggs or eggshell fragments from 12 nests. Mean thickness of shell fragments, without membrane, was 0.46 mm, 34% lower than the average thickness of 0.70 mm of fragments recovered from nine successful nests in interior southern California, 2007-2009. Hatching success in central California was 20-40%, significantly lower than the 70-80% recorded in southern California. The outer crystalline layer was absent or greatly reduced, as in thin-shelled condor eggs laid in southern California in the 1960s. Shell thickness was not related to egg size. Weight/water loss during incubation in the wild averaged three times greater than the normal rate associated with successful hatching; the rate of loss increased significantly with decreasing shell thickness. At least four failures, three from death of the embryo, we attribute to excessive weight/water loss; two other eggs losing substantial weight hatched successfully after artificial incubation at elevated humidities. DDT/DDE from wastes of a DDT factory discharged into the Southern California Bight had previously caused extensive eggshell thinning and reproductive failures of fish-eating and raptorial birds. Feeding on carcasses of California sea lions (Zalophus californianus), reintroduced condors now occupy a higher level of the food web. Like that of other species previously affected, the thickness of condor eggshells should recover as DDE contamination continues to decline. © The Cooper Ornithological Society 2013.


Rivers J.W.,Oregon State University | Johnson J.M.,U.S. Geological Survey | Johnson J.M.,U.S. Department of Agriculture | Haig S.M.,U.S. Geological Survey | And 5 more authors.
Bird Conservation International | Year: 2014

Condors and vultures comprise the only group of terrestrial vertebrates in the world that are obligate scavengers, and these species move widely to locate ephemeral, unpredictable, and patchily-distributed food resources. In this study, we used high-resolution GPS location data to quantify monthly home range size of the critically endangered California Condor Gymnogyps californianus throughout the annual cycle in California. We assessed whether individual-level characteristics (age, sex and breeding status) and factors related to endangered species recovery program efforts (rearing method, release site) were linked to variation in monthly home range size. We found that monthly home range size varied across the annual cycle, with the largest monthly home ranges observed during late summer and early fall (July-October), a pattern that may be linked to seasonal changes in thermals that facilitate movement. Monthly home ranges of adults were significantly larger than those of immatures, but males and females used monthly home ranges of similar size throughout the year and breeding adults did not differ from non-breeding adults in their average monthly home range size. Individuals from each of three release sites differed significantly in the size of their monthly home ranges, and no differences in monthly home range size were detected between condors reared under captive conditions relative to those reared in the wild. Our study provides an important foundation for understanding the movement ecology of the California Condor and it highlights the importance of seasonal variation in space use for effective conservation planning for this critically endangered species. Copyright © 2014 BirdLife International.


Finkelstein M.E.,University of California at Santa Cruz | Kuspa Z.E.,University of California at Santa Cruz | Welch A.,National Park Service | Eng C.,Los Angeles Zoo and Botanical Gardens | And 3 more authors.
Environmental research | Year: 2014

Lead poisoning is preventing the recovery of the critically endangered California condor (Gymnogyps californianus) and lead isotope analyses have demonstrated that ingestion of spent lead ammunition is the principal source of lead poisoning in condors. Over an 8 month period in 2009, three lead-poisoned condors were independently presented with birdshot embedded in their tissues, evidencing they had been shot. No information connecting these illegal shooting events existed and the timing of the shooting(s) was unknown. Using lead concentration and stable lead isotope analyses of feathers, blood, and recovered birdshot, we observed that: i) lead isotope ratios of embedded shot from all three birds were measurably indistinguishable from each other, suggesting a common source; ii) lead exposure histories re-constructed from feather analysis suggested that the shooting(s) occurred within the same timeframe; and iii) two of the three condors were lead poisoned from a lead source isotopically indistinguishable from the embedded birdshot, implicating ingestion of this type of birdshot as the source of poisoning. One of the condors was subsequently lead poisoned the following year from ingestion of a lead buckshot (blood lead 556 µg/dL), illustrating that ingested shot possess a substantially greater lead poisoning risk compared to embedded shot retained in tissue (blood lead ~20 µg/dL). To our knowledge, this is the first study to use lead isotopes as a tool to retrospectively link wildlife shooting events. Copyright © 2014 Elsevier Inc. All rights reserved.


Finkelstein M.E.,University of California at Santa Cruz | George D.,National Park Service | Scherbinski S.,National Park Service | Gwiazda R.,University of California at Santa Cruz | And 9 more authors.
Environmental Science and Technology | Year: 2010

Lead poisoning is a primary factor impeding the survival and recovery of the critically endangered California Condor (Gymnogyps californianus). However, the frequency and magnitude of lead exposure in condors is not well-known in part because most blood lead monitoring occurs biannually, and biannual blood samples capture only ∼10% of a bird's annual exposure history. We investigated the use of growing feathers from free-flying condors in California to establish a bird's lead exposure history. We show that lead concentration and stable lead isotopic composition analyses of sequential feather sections and concurrently collected blood samples provided a comprehensive history of lead exposure over the 2-4 month period of feather growth. Feather analyses identified exposure events not evident from blood monitoring efforts, and by fitting an empirically derived timeline to actively growing feathers, we were able to estimate the time frame for specific lead exposure events. Our results demonstrate the utility of using sequentially sampled feathers to reconstruct lead exposure history. Since exposure risk in individuals is one determinant © 2010 American Chemical Society.


Rivers J.W.,Oregon State University | Johnson J.M.,U.S. Geological Survey | Johnson J.M.,U.S. Department of Agriculture | Haig S.M.,U.S. Geological Survey | And 4 more authors.
PLoS ONE | Year: 2014

Condors and vultures are distinct from most other terrestrial birds because they use extensive soaring flight for their daily movements. Therefore, assessing resource selection by these avian scavengers requires quantifying the availability of terrestrial-based habitats, as well as meteorological variables that influence atmospheric conditions necessary for soaring. In this study, we undertook the first quantitative assessment of habitat- and meteorological-based resource selection in the endangered California condor (Gymnogyps californianus) within its California range and across the annual cycle. We found that condor use of terrestrial areas did not change markedly within the annual cycle, and that condor use was greatest for habitats where food resources and potential predators could be detected and where terrain was amenable for taking off from the ground in flight (e.g., sparse habitats, coastal areas). Condors originating from different release sites differed in their use of habitat, but this was likely due in part to variation in habitats surrounding release sites. Meteorological conditions were linked to condor use of ecological subregions, with thermal height, thermal velocity, and wind speed having both positive (selection) and negative (avoidance) effects on condor use in different areas. We found little evidence of systematic effects between individual characteristics (i.e., sex, age, breeding status) or components of the species management program (i.e., release site, rearing method) relative to meteorological conditions. Our findings indicate that habitat type and meteorological conditions can interact in complex ways to influence condor resource selection across landscapes, which is noteworthy given the extent of anthropogenic stressors that may impact condor populations (e.g., lead poisoning, wind energy development). Additional studies will be valuable to assess small-scale condor movements in light of these stressors to help minimize their risk to this critically endangered species.


PubMed | Los Angeles Zoo and Botanical Gardens, National Park Service, University of California at Santa Cruz and Ventana Wildlife Society
Type: | Journal: Environmental research | Year: 2014

Lead poisoning is preventing the recovery of the critically endangered California condor (Gymnogyps californianus) and lead isotope analyses have demonstrated that ingestion of spent lead ammunition is the principal source of lead poisoning in condors. Over an 8 month period in 2009, three lead-poisoned condors were independently presented with birdshot embedded in their tissues, evidencing they had been shot. No information connecting these illegal shooting events existed and the timing of the shooting(s) was unknown. Using lead concentration and stable lead isotope analyses of feathers, blood, and recovered birdshot, we observed that: i) lead isotope ratios of embedded shot from all three birds were measurably indistinguishable from each other, suggesting a common source; ii) lead exposure histories re-constructed from feather analysis suggested that the shooting(s) occurred within the same timeframe; and iii) two of the three condors were lead poisoned from a lead source isotopically indistinguishable from the embedded birdshot, implicating ingestion of this type of birdshot as the source of poisoning. One of the condors was subsequently lead poisoned the following year from ingestion of a lead buckshot (blood lead 556 g/dL), illustrating that ingested shot possess a substantially greater lead poisoning risk compared to embedded shot retained in tissue (blood lead ~20 g/dL). To our knowledge, this is the first study to use lead isotopes as a tool to retrospectively link wildlife shooting events.


PubMed | Simon Fraser University, Ventana Wildlife Society, U.S. Geological Survey, U.S. Fish and Wildlife Service and 3 more.
Type: Journal Article | Journal: PloS one | Year: 2014

Condors and vultures are distinct from most other terrestrial birds because they use extensive soaring flight for their daily movements. Therefore, assessing resource selection by these avian scavengers requires quantifying the availability of terrestrial-based habitats, as well as meteorological variables that influence atmospheric conditions necessary for soaring. In this study, we undertook the first quantitative assessment of habitat- and meteorological-based resource selection in the endangered California condor (Gymnogyps californianus) within its California range and across the annual cycle. We found that condor use of terrestrial areas did not change markedly within the annual cycle, and that condor use was greatest for habitats where food resources and potential predators could be detected and where terrain was amenable for taking off from the ground in flight (e.g., sparse habitats, coastal areas). Condors originating from different release sites differed in their use of habitat, but this was likely due in part to variation in habitats surrounding release sites. Meteorological conditions were linked to condor use of ecological subregions, with thermal height, thermal velocity, and wind speed having both positive (selection) and negative (avoidance) effects on condor use in different areas. We found little evidence of systematic effects between individual characteristics (i.e., sex, age, breeding status) or components of the species management program (i.e., release site, rearing method) relative to meteorological conditions. Our findings indicate that habitat type and meteorological conditions can interact in complex ways to influence condor resource selection across landscapes, which is noteworthy given the extent of anthropogenic stressors that may impact condor populations (e.g., lead poisoning, wind energy development). Additional studies will be valuable to assess small-scale condor movements in light of these stressors to help minimize their risk to this critically endangered species.


News Article | November 8, 2016
Site: www.prweb.com

Oakland Zoo has raised over $104,000 this past year through ‘Quarters for Conservation,’ an ongoing program where 25¢ of every ticket sold is designated for helping animals in the wild through the Zoo’s conservation partners worldwide. “The future of wild animals is in the hands of each and every one of us and it is our job as a conservation-focused zoo to engage our community in real wildlife conservation actions. With Quarters for Conservation, our visitors are taking action every time they visit the zoo. We thank our community for their role in offering vital support to these inspirational projects,” said Amy Gotliffe, Director of Conservation at Oakland Zoo. Fifty percent of the funds will go directly to three featured conservation programs in the field that help save wolves, chimpanzees, and Bay Area birds. The three recipients of the funds this past year are The California Wolf Center, the Budongo Snare Removal Project in Uganda, and the Golden Gate Audubon Society. "California Wolf Center is incredibly grateful to have been involved in Oakland Zoo's Quarters for Conservation program this year. We are honored to be supported by an organization that so highly values preservation of wild species and their habitat. Wild wolves thank the Oakland Zoo!," Christina Souto, Associate Director of California Wolf Recovery, California Wolf Center. Twenty-five percent of the funds raised will be used towards Oakland Zoo’s onsite conservation programs such as veterinary care for wild California condors and the Western Pond Turtle head-start program. The remaining twenty-five percent of the monies helps support the Zoo’s conservation field partners around the world, including: ARCAS, the Bay Area Puma Project, Bornean Sun Bear Conservation Center, the Kibale Fuel Wood Project, the Reticulated Giraffe Project, the Marine Mammal Center, the Mountain Lion Foundation, EWASO Lions, Ventana Wildlife Society, and the Uganda Carnivore Program. Oakland Zoo’s Quarters for Conservation Program has raised more than $500,000 since it launched in 2012. Now, a new year of Quarters for Conservation (Q4C) begins again with featured beneficiaries including Proyecto Tití for cotton-top tamarins, the Iinnii Initiative for bison, and Oakland Zoo’s Biodiversity Program for amphibians. See below descriptions for additional information about the 2017 partners: Proyecto Tití (South America) Cotton-top tamarins are tiny monkeys that only exist in the tropical forests of northern Colombia in South America. They are losing their home to deforestation, and are also victims of the illegal pet trade. Proyecto Tití (Project Tamarin) is working to guarantee a future for this charismatic little monkey, by protecting their habitat and working with local communities, providing conservation education and income alternatives to reduce the unsustainable use of forest resources. "We are so happy Cotton-top tamarins and Proyecto Tití were chosen as one of the Quarters for Conservation projects; it's exciting to know that many more people will be able to learn about the 'cutest' monkey on earth, and about our hard work to secure a long-term future for this amazing and charismatic primate, which is in the brink of extinction." – Rosamira Guillen, Executive Director, Fundación Proyecto Tití Iinnii Initiative (Montana, USA) Bison, North America’s largest land mammal, once roamed the continent and played an important role in the prairie landscape. But today, wild bison are absent from most of their historic range, and their genetic diversity is threatened by isolated herds. Native Americans have long had an important spiritual and cultural relationship with bison. Oakland Zoo has partnered with the Blackfeet Nation and Wildlife Conservation Society (WCS) through the Iinnii Initiative, which will return bison to tribal lands in Montana, provide educational programs, and promote bison conservation and cultural preservation. “We are excited to have Oakland Zoo’s partnership in the Iinnii Initiative, which has and will continue to push forward the cultural and ecological significance of bison on the restoration of the Glacier-Waterton landscape,” Keith Aune, Director, Bison Conservation Program, WCS North America Oakland Zoo’s Biodiversity Program Frogs and toads may be small, but they are important species that show how healthy their environment is. All around the world, amphibians are struggling with the threats of habitat loss, climate change, non-native predators, and disease. Oakland Zoo’s Biodiversity Program is working to save these special animals through intensive onsite conservation efforts for Puerto Rican Crested Toads and Mountain Yellow-Legged Frogs. “Amphibian populations are declining at a much faster rate than either birds or mammals. In fact, more than 30% of the world’s amphibian species are currently threatened with extinction, including the two species in Oakland Zoo’s Biodiversity Program. Quarters for Conservation funds will allow us to breed and/or treat the critically endangered Puerto Rican Crested Toads and Mountain Yellow-Legged Frogs so they can re-populate in the wild,” said Margaret Rousser, Zoological Manager, Oakland Zoo. For more information on the above programs, visit: http://www.oaklandzoo.org//Quarters_4Conservation.php ABOUT OAKLAND ZOO The Bay Area's award-winning Oakland Zoo is home to more than 660 native and exotic animals. The Zoo offers many educational programs and kid's activities perfect for science field trips, family day trips and exciting birthday parties. Oakland Zoo is dedicated to the humane treatment of animals and wildlife conservation onsite and worldwide; with 25¢ from each ticket donated to support conservation partners and programs around the world. The California Trail, a transformational project that more than doubles our size, opens in 2018, and will further our commitment to animal care, education, and conservation with a focus on this state’s remarkable native wildlife. Nestled in the Oakland Hills, in 500-acre Knowland Park, the Zoo is located at 9777 Golf Links Road, off Highway 580. The East Bay Zoological Society (Oakland Zoo) is a nonprofit 501(c)3 organization supported in part by members, contributions, the City of Oakland and the East Bay Regional Parks. For more information, go to: http://www.oaklandzoo.org


Stake M.M.,Ventana Wildlife Society | Sorenson K.,Ventana Wildlife Society
Western Birds | Year: 2011

We assessed trends in rates of capture of eight riparian songbirds mist-netted over 17 years (1993-2009) at Big Sur, on the central California coast. The Warbling Vireo (Vireo giluus) and Yellow Warbler (Dendroica petechia) declined significantly, whereas the Swainsons Thrush (Catharus ustulatus) showed a nearly significant increase. Rates of capture of the Willow Flycatcher (Empidonax trailla), Wilson's Warbler (Wilsonia pusilla), Common Yellowthroat (Geothlypis trichas), Yellow-breasted Chat (Icteria uirens), and Black-headed Grosbeak (Pheucticus melanocephalus) were stable. Negative trends for the Warbling Vireo and Yellow Warbler were particularly strong for hatching-year birds, indicating that factors acting in the breeding season were responsible for declines. We captured high ratios of transients to local adults, and at Big Sur trends for some of these species are associated more with populations breeding in other regions. However, in the Swainson's Thrush and Wilson's Warbler, we observed significant increases in local adults and local hatching-year birds, indicating the importance of local riparian habitat for some species at Big Sur.

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