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Michael N Romanov - One of the best experts on this subject based on the ideXlab platform.
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Whole genome sequencing of California Condors is now utilized for guiding genetic management
2016Co-Authors: Oliver A. Ryder, Michael N Romanov, Leona G. Chemnick, Katherine Ralls, Jonathan D. Ballou, Michael Mace, Webb Miller, Cynthia C. Steiner, Anna Mitelberg, Stephan C. SchusterAbstract:The California Condor is a critically endangered avian species that, in 1982, became extinct in the wild. Its survival has persevered through a captive breeding program and reintroduction efforts within its former range. As of April, 2015, 421 California Condors, including 204 flying in the wild constituted the extant population. Concern regarding preservation of genetic diversity and inbreeding, have led to intensive population management supported by molecular genetics research and, more recently, the application of genomic methodologies. 36 complete California Condor genomes, representing the whole gene pool of the species, have been sequenced identifying about 4 millions polymorphic sites (SNPs). This has allowed reassessment of kinship among the founder birds, which is now being applied to selecting breeding pairs for the ongoing captive propagation effort. A genetic disease, chondrodystrophy, is inherited consistent with an autosomal recessive mode of transmission in Condors. Utilizing whole genome sequencing of affected chicks and their carrier parents, a series of linked markers localized in a 1 Mb region of the Condor genome have been employed to detect carrier Condors heterozygous for the lethal mutation. This information can be incorporated into population management to reduce the risk of reproductive failure, as reintroduced populations begin to expand.
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Supporting California Condor conservation management through analysis of species-wide whole genome sequence variation
2014Co-Authors: Oliver A. Ryder, Michael N Romanov, Leona G. Chemnick, Steven M. Thomas, Jessica Martin, Katherine Ralls, Jonathan D. Ballou, Michael Mace, Aakrosh Ratan, Webb MillerAbstract:The critically endangered California Condor (Gymnogyps Californianus) has been the focus of intensive conservation efforts for several decades. Reduced to a population size of twenty-three birds in 1985, the entire surviving population was brought under captive management for recovery. Founded by fourteen individuals, the surviving California Condor gene pool has been managed through captive breeding of individuals paired through pedigree analysis. As of August, 2013, there were 424 California Condor individuals; 223 are flying in the wild in four re-introduced populations in California, Arizona and Baja California, Mexico. All Condors have their sex identified via amplification of sex chromosome specific markers and DNA samples are stored for every individual of the species. Microsatellite genotyping has confirmed parentage in captive and wild Condor chicks, corrected switched identities, and identified successful extra-pair copulation in the wild population. Whole genome sequencing using data generated on multiple platforms has been used to produce a de novo genome assembly for a founder male Condor and thirty additional Condors that together encompass the entire genetic variation of the species, perhaps the first time such a comprehensive effort has been conducted for any species. Studbook-based kinship relationships between founder birds and kinship estimates from genome-wide genetic variation can be compared and evaluated in the context of retention of genetic diversity in the generations of California Condors. Genomic studies of California Condors are providing a model system for avian conservation genomics and allow empirical evaluation of basic facets of transmission genetics, including segregation, linkage, recombination and mutation.
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Molecular cytogenetics of the California Condor: evolutionary and conservation implications
Cytogenetic and genome research, 2009Co-Authors: William S. Modi, Michael N Romanov, Eric D. Green, Oliver A. RyderAbstract:Evolutionary cytogenetic comparisons involved 5 species of birds (California Condor, chicken, zebra finch, collared flycatcher and black stork) belonging to divergent taxonomic orders. Seventy-four clones from a Condor BAC library containing 80 genes were mapped to Condor chromosomes using FISH, and 15 clones containing 16 genes were mapped to the stork Z chromosome. Maps for chicken and finch were derived from genome sequence databases, and that for flycatcher from the published literature. Gene content and gene order were highly conserved when individual Condor, chicken, and zebra finch autosomes were compared, confirming that these species largely retain karyotypes close to the ancestral condition for neognathous birds. However, several differences were noted: zebra finch chromosomes 1 and 1A are homologous to Condor and chicken chromosomes 1, the CHUNK1 gene appears to have transposed on Condor chromosome 1, Condor chromosomes 4 and 9 and zebra finch chromosomes 4 and 4A are homologous to chicken chromosome arms 4q and 4p, and novel inversions on chromosomes 4, 12 and 13 were found. Condor and stork Z chromosome gene orders are collinear and differentiated by a series of inversions/transpositions when compared to chicken, zebra finch, or flycatcher; phylogenetic analyses suggest independent rearrangement along the chicken, finch, and flycatcher lineages.
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The value of avian genomics to the conservation of wildlife
BMC Genomics, 2009Co-Authors: Michael N Romanov, Marisa L. Korody, William S. Modi, Emily M Stremel Mork, Christie A Otten, Tanya Renner, Elaina M Tuttle, Marlys L. Houck, Leona G. Chemnick, Kenneth C. JonesAbstract:Background Genomic studies in non-domestic avian models, such as the California Condor and white-throated sparrow, can lead to more comprehensive conservation plans and provide clues for understanding mechanisms affecting genetic variation, adaptation and evolution. Developing genomic tools and resources including genomic libraries and a genetic map of the California Condor is a prerequisite for identification of candidate loci for a heritable embryonic lethal condition. The white-throated sparrow exhibits a stable genetic polymorphism (i.e. chromosomal rearrangements) associated with variation in morphology, physiology, and behavior (e.g., aggression, social behavior, sexual behavior, parental care). In this paper we outline the utility of these species as well as report on recent advances in the study of their genomes. Results Genotyping of the Condor resource population at 17 microsatellite loci provided a better assessment of the current population's genetic variation. Specific New World vulture repeats were found in the Condor genome. Using Condor BAC library and clones, chicken-Condor comparative maps were generated. A Condor fibroblast cell line transcriptome was characterized using the 454 sequencing technology. Our karyotypic analyses of the sparrow in combination with other studies indicate that the rearrangements in both chromosomes 2^m and 3^a are complex and likely involve multiple inversions, interchromosomal linkage, and pleiotropy. At least a portion of the rearrangement in chromosome 2^m existed in the common ancestor of the four North American species of Zonotrichia , but not in the one South American species, and that the 2^m form, originally thought to be the derived condition, might actually be the ancestral one. Conclusion Mining and characterization of candidate loci in the California Condor using molecular genetic and genomic techniques as well as linkage and comparative genomic mapping will eventually enable the identification of carriers of the chondrodystrophy allele, resulting in improved genetic management of this disease. In the white-throated sparrow, genomic studies, combined with ecological data, will help elucidate the basis of genic selection in a natural population. Morphs of the sparrow provide us with a unique opportunity to study intraspecific genomic differences, which have resulted from two separate yet linked evolutionary trajectories. Such results can transform our understanding of evolutionary and conservation biology.
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the value of avian genomics to the conservation of wildlife
BMC Genomics, 2009Co-Authors: Michael N Romanov, Marisa L. Korody, William S. Modi, Christie A Otten, Elaina M Tuttle, Marlys L. Houck, Leona G. Chemnick, Emily Stremel M Mork, Tanya RennerAbstract:Genomic studies in non-domestic avian models, such as the California Condor and white-throated sparrow, can lead to more comprehensive conservation plans and provide clues for understanding mechanisms affecting genetic variation, adaptation and evolution. Developing genomic tools and resources including genomic libraries and a genetic map of the California Condor is a prerequisite for identification of candidate loci for a heritable embryonic lethal condition. The white-throated sparrow exhibits a stable genetic polymorphism (i.e. chromosomal rearrangements) associated with variation in morphology, physiology, and behavior (e.g., aggression, social behavior, sexual behavior, parental care). In this paper we outline the utility of these species as well as report on recent advances in the study of their genomes. Genotyping of the Condor resource population at 17 microsatellite loci provided a better assessment of the current population's genetic variation. Specific New World vulture repeats were found in the Condor genome. Using Condor BAC library and clones, chicken-Condor comparative maps were generated. A Condor fibroblast cell line transcriptome was characterized using the 454 sequencing technology. Our karyotypic analyses of the sparrow in combination with other studies indicate that the rearrangements in both chromosomes 2m and 3a are complex and likely involve multiple inversions, interchromosomal linkage, and pleiotropy. At least a portion of the rearrangement in chromosome 2m existed in the common ancestor of the four North American species of Zonotrichia, but not in the one South American species, and that the 2m form, originally thought to be the derived condition, might actually be the ancestral one. Mining and characterization of candidate loci in the California Condor using molecular genetic and genomic techniques as well as linkage and comparative genomic mapping will eventually enable the identification of carriers of the chondrodystrophy allele, resulting in improved genetic management of this disease. In the white-throated sparrow, genomic studies, combined with ecological data, will help elucidate the basis of genic selection in a natural population. Morphs of the sparrow provide us with a unique opportunity to study intraspecific genomic differences, which have resulted from two separate yet linked evolutionary trajectories. Such results can transform our understanding of evolutionary and conservation biology.
Oliver A. Ryder - One of the best experts on this subject based on the ideXlab platform.
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genome wide diversity in the California Condor tracks its prehistoric abundance and decline
Current Biology, 2021Co-Authors: Jacqueline Robinson, Oliver A. Ryder, Cynthia C. Steiner, Rauri C K Bowie, Olga Dudchenko, Erez Lieberman Aiden, Sher L Hendrickson, David P Mindell, Jeffrey D WallAbstract:Due to their small population sizes, threatened and endangered species frequently suffer from a lack of genetic diversity, potentially leading to inbreeding depression and reduced adaptability.1 During the latter half of the twentieth century, North America's largest soaring bird,2 the California Condor (Gymnogyps Californianus; Critically Endangered3), briefly went extinct in the wild. Though Condors once ranged throughout North America, by 1982 only 22 individuals remained. Following decades of captive breeding and release efforts, there are now >300 free-flying wild Condors and ∼200 in captivity. The Condor's recent near-extinction from lead poisoning, poaching, and loss of habitat is well documented,4 but much about its history remains obscure. To fill this gap and aid future management of the species, we produced a high-quality chromosome-length genome assembly for the California Condor and analyzed its genome-wide diversity. For comparison, we also examined the genomes of two close relatives: the Andean Condor (Vultur gryphus; Vulnerable3) and the turkey vulture (Cathartes aura; Least Concern3). The genomes of all three species show evidence of historic population declines. Interestingly, the California Condor genome retains a high degree of variation, which our analyses reveal is a legacy of its historically high abundance. Correlations between genome-wide diversity and recombination rate further suggest a history of purifying selection against linked deleterious alleles, boding well for future restoration. We show how both long-term evolutionary forces and recent inbreeding have shaped the genome of the California Condor, and provide crucial genomic resources to enable future research and conservation.
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Whole genome sequencing of California Condors is now utilized for guiding genetic management
2016Co-Authors: Oliver A. Ryder, Michael N Romanov, Leona G. Chemnick, Katherine Ralls, Jonathan D. Ballou, Michael Mace, Webb Miller, Cynthia C. Steiner, Anna Mitelberg, Stephan C. SchusterAbstract:The California Condor is a critically endangered avian species that, in 1982, became extinct in the wild. Its survival has persevered through a captive breeding program and reintroduction efforts within its former range. As of April, 2015, 421 California Condors, including 204 flying in the wild constituted the extant population. Concern regarding preservation of genetic diversity and inbreeding, have led to intensive population management supported by molecular genetics research and, more recently, the application of genomic methodologies. 36 complete California Condor genomes, representing the whole gene pool of the species, have been sequenced identifying about 4 millions polymorphic sites (SNPs). This has allowed reassessment of kinship among the founder birds, which is now being applied to selecting breeding pairs for the ongoing captive propagation effort. A genetic disease, chondrodystrophy, is inherited consistent with an autosomal recessive mode of transmission in Condors. Utilizing whole genome sequencing of affected chicks and their carrier parents, a series of linked markers localized in a 1 Mb region of the Condor genome have been employed to detect carrier Condors heterozygous for the lethal mutation. This information can be incorporated into population management to reduce the risk of reproductive failure, as reintroduced populations begin to expand.
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Supporting California Condor conservation management through analysis of species-wide whole genome sequence variation
2014Co-Authors: Oliver A. Ryder, Michael N Romanov, Leona G. Chemnick, Steven M. Thomas, Jessica Martin, Katherine Ralls, Jonathan D. Ballou, Michael Mace, Aakrosh Ratan, Webb MillerAbstract:The critically endangered California Condor (Gymnogyps Californianus) has been the focus of intensive conservation efforts for several decades. Reduced to a population size of twenty-three birds in 1985, the entire surviving population was brought under captive management for recovery. Founded by fourteen individuals, the surviving California Condor gene pool has been managed through captive breeding of individuals paired through pedigree analysis. As of August, 2013, there were 424 California Condor individuals; 223 are flying in the wild in four re-introduced populations in California, Arizona and Baja California, Mexico. All Condors have their sex identified via amplification of sex chromosome specific markers and DNA samples are stored for every individual of the species. Microsatellite genotyping has confirmed parentage in captive and wild Condor chicks, corrected switched identities, and identified successful extra-pair copulation in the wild population. Whole genome sequencing using data generated on multiple platforms has been used to produce a de novo genome assembly for a founder male Condor and thirty additional Condors that together encompass the entire genetic variation of the species, perhaps the first time such a comprehensive effort has been conducted for any species. Studbook-based kinship relationships between founder birds and kinship estimates from genome-wide genetic variation can be compared and evaluated in the context of retention of genetic diversity in the generations of California Condors. Genomic studies of California Condors are providing a model system for avian conservation genomics and allow empirical evaluation of basic facets of transmission genetics, including segregation, linkage, recombination and mutation.
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Molecular cytogenetics of the California Condor: evolutionary and conservation implications
Cytogenetic and genome research, 2009Co-Authors: William S. Modi, Michael N Romanov, Eric D. Green, Oliver A. RyderAbstract:Evolutionary cytogenetic comparisons involved 5 species of birds (California Condor, chicken, zebra finch, collared flycatcher and black stork) belonging to divergent taxonomic orders. Seventy-four clones from a Condor BAC library containing 80 genes were mapped to Condor chromosomes using FISH, and 15 clones containing 16 genes were mapped to the stork Z chromosome. Maps for chicken and finch were derived from genome sequence databases, and that for flycatcher from the published literature. Gene content and gene order were highly conserved when individual Condor, chicken, and zebra finch autosomes were compared, confirming that these species largely retain karyotypes close to the ancestral condition for neognathous birds. However, several differences were noted: zebra finch chromosomes 1 and 1A are homologous to Condor and chicken chromosomes 1, the CHUNK1 gene appears to have transposed on Condor chromosome 1, Condor chromosomes 4 and 9 and zebra finch chromosomes 4 and 4A are homologous to chicken chromosome arms 4q and 4p, and novel inversions on chromosomes 4, 12 and 13 were found. Condor and stork Z chromosome gene orders are collinear and differentiated by a series of inversions/transpositions when compared to chicken, zebra finch, or flycatcher; phylogenetic analyses suggest independent rearrangement along the chicken, finch, and flycatcher lineages.
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Genomic resources and tools to investigate factors associated with chondrodystrophy in California Condors
2007Co-Authors: Michael N Romanov, William S. Modi, Oliver A. Ryder, Maxim Koriabine, Mikhail Nefedov, Pieter J. De Jong, Jerry B. DodgsonAbstract:The California Condor is among the endangered avian species under captive management for which genetic and genomic investigation technologies are being developed. A genetic form of chondrodystrophy in Condors was previously identified that appears to be inherited as an autosomal recessive allele. The ongoing research project is aimed at (i) initiating development of a genetic map of the California Condor, (ii) evaluating the candidate genes responsible for heritable chondrodystrophy, and (iii) producing a carrier test for individuals possessing the gene. To address genome research and genetic management of California Condors, we have begun to develop genetic, cytogenetic and comparative maps as a prerequisite for identification of candidate loci for the chondrodystrophy mutation. We produced a highly redundant California Condor genomic BAC library that was used to construct a first-generation chicken-Condor comparative physical map and to identify specific Condor BACs carrying candidate genes for chondrodystrophy. Sequencing and characterization of candidate loci are underway that will enable us to identify carriers of the chondrodystrophy allele and provide tools for improved genetic management of this disease.
Donald R. Smith - One of the best experts on this subject based on the ideXlab platform.
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Lead Exposure Risk from Trash Ingestion by the Endangered California Condor (Gymnogyps Californianus)
Journal of wildlife diseases, 2015Co-Authors: Myra E. Finkelstein, Joseph Brandt, Jesse Grantham, Estelle A. Sandhaus, Allan Mee, Patricia Jill Schuppert, Donald R. SmithAbstract:Abstract Lead poisoning from ingestion of spent lead ammunition is one of the greatest threats to the recovery of California Condors (Gymnogyps Californianus) in the wild. Trash ingestion by Condors is well documented, yet the extent that trash presents a lead exposure risk is unknown. We evaluated 1,413 trash items collected from Condor nest areas and nestlings in the Transverse Range of Ventura County, California, US, from 2002 to 2008, for their potential as a lead exposure risk to Condors. We visually identified 71 items suspected to contain sufficient lead to be of toxicologic concern. These items were leached with weak acid and analyzed for lead. Twenty-seven of the 71 leached items (~2% of the 1,413 items) were “lead containing” based on criteria of a leachate lead concentration >1 μg/mL, with the majority of these items (22; 81% of the 27 lead items) being ammunition related (e.g., spent bullet casings and jacketed bullets). Only three of the 1,413 items collected were lead containing but were cle...
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Linking cases of illegal shootings of the endangered California Condor using stable lead isotope analysis.
Environmental research, 2014Co-Authors: Myra E. Finkelstein, Zeka Kuspa, Alacia Welch, Curtis Eng, Michael Clark, Joseph Burnett, Donald R. SmithAbstract: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.
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Discrimination Factors for Stable Isotopes of Carbon and Nitrogen in Blood and Feathers from Chicks and Juveniles of the California Condor
The Condor, 2013Co-Authors: Carolyn M. Kurle, Daniel George, Myra E. Finkelstein, Kimberly R. Smith, Debbie Ciani, Paul L. Koch, Donald R. SmithAbstract:Abstract. Stable-isotope ratios of carbon (13C/12C; δ13C) and nitrogen (15N/14N; δ15N) in animal tissues are analyzed to estimate animal foraging ecology because these ratios reflect those of an animal's diet. This reflection is generally indirect, as stable-isotope ratios change with trophic level. These differences, called discrimination factors (reported as Δ), vary considerably by species and tissue. Variations in discrimination factors used in stableisotope mixing models can lead to inaccurate estimates of diets. Therefore, determining accurate discrimination factors specific to species and tissue is important. We established the Δ13C and Δ15N values between diet and blood and feathers from chicks and juveniles of the California Condor (Gymnogyps Californianus). Hatchlings were fed rats for 76–119 days, whereas juveniles were fed dairy calves for 64 days. The mean Δ13C and Δ15N values (± SD) between chick feathers and rat muscle were 0.4 ± 0.4‰ and 3.1 ± 0.2‰, respectively; those between chicks' whol...
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Lead poisoning and the deceptive recovery of the critically endangered California Condor
Proceedings of the National Academy of Sciences of the United States of America, 2012Co-Authors: Myra E. Finkelstein, Joseph Brandt, Daniel George, Jesse Grantham, Daniel F. Doak, Joe Burnett, Molly E Me Church, Donald R. SmithAbstract:Endangered species recovery programs seek to restore populations to self-sustaining levels. Nonetheless, many recovering species require continuing management to compensate for persistent threats in their environment. Judging true recovery in the face of this management is often difficult, impeding thorough analysis of the success of conservation programs. We illustrate these challenges with a multidisciplinary study of one of the world’s rarest birds—the California Condor (Gymnogyps Californianus). California Condors were brought to the brink of extinction, in part, because of lead poisoning, and lead poisoning remains a significant threat today. We evaluated individual lead-related health effects, the efficacy of current efforts to prevent lead-caused deaths, and the consequences of any reduction in currently intensive management actions. Our results show that Condors in California remain chronically exposed to harmful levels of lead; 30% of the annual blood samples collected from Condors indicate lead exposure (blood lead ≥ 200 ng/mL) that causes significant subclinical health effects, measured as >60% inhibition of the heme biosynthetic enzyme δ-aminolevulinic acid dehydratase. Furthermore, each year, ∼20% of free-flying birds have blood lead levels (≥450 ng/mL) that indicate the need for clinical intervention to avert morbidity and mortality. Lead isotopic analysis shows that lead-based ammunition is the principle source of lead poisoning in Condors. Finally, population models based on Condor demographic data show that the Condor’s apparent recovery is solely because of intensive ongoing management, with the only hope of achieving true recovery dependent on the elimination or substantial reduction of lead poisoning rates.
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Patterns of mortality in free-ranging California Condors (Gymnogyps Californianus).
Journal of wildlife diseases, 2012Co-Authors: Bruce A. Rideout, Michael Mace, Myra E. Finkelstein, Donald R. Smith, Ilse I Stalis, Rebecca Papendick, Allan A Pessier, Birgit Puschner, Matthew Johnson, Richard R StroudAbstract: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 self-sustaining populations in the wild. A total of 135 deaths occurred from October 1992 (the first post-release 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.
Joseph Brandt - One of the best experts on this subject based on the ideXlab platform.
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meteorological and environmental variables affect flight behaviour and decision making of an obligate soaring bird the California Condor gymnogyps Californianus
Ibis, 2018Co-Authors: Sharon A. Poessel, Joseph Brandt, Tricia A Miller, Todd E. KatznerAbstract:The movements of animals are limited by evolutionary constraints and ecological processes and are strongly influenced by the medium through which they travel. For flying animals, variation in atmospheric conditions are critically influential in movement. Obligate soaring birds depend on external sources of updraft more than do other flying species, since without that updraft they are unable to sustain flight for extended periods. These species are therefore good models for understanding how the environment can influence decisions about movement. We used meteorological and topographic variables to understand the environmental influences on the decision to engage in flight by obligate soaring and critically endangered California Condors Gymnogyps Californianus. Condors were more likely to fly, soared at higher altitudes, and flew over smoother terrain when weather conditions promoted either thermal or orographic updrafts, for example when turbulence and solar radiation were higher and when winds from the east and north were stronger. However, increased atmospheric stability, which is inconsistent with thermal development but may be associated with orographic updrafts, was correlated with a somewhat higher probability of lower flight altitudes and flight over rougher terrain. The close and previously undescribed linkages between Condor flight and conditions that support development of thermal and orographic updrafts provide important insight into the behaviour of obligate soaring birds and into the environmental parameters that may define the currently expanding distribution of Condors within and outside of the state of California. This article is protected by copyright. All rights reserved.
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Flight response to spatial and temporal correlates informs risk from wind turbines to the California Condor
The Condor, 2018Co-Authors: Sharon A. Poessel, Joseph Brandt, Laura C. Mendenhall, Melissa A. Braham, Michael Lanzone, Andrew J. Mcgann, Todd E. KatznerAbstract:ABSTRACT Wind power is a fast-growing energy resource, but wind turbines can kill volant wildlife, and the flight behavior of obligate soaring birds can place them at risk of collision with these structures. We analyzed altitudinal data from GPS telemetry of critically endangered California Condors (Gymnogyps Californianus) to assess the circumstances under which their flight behavior may place them at risk from collision with wind turbines. Condor flight behavior was strongly influenced by topography and land cover, and birds flew at lower altitudes and closer to the rotor-swept zone of wind turbines when over ridgelines and steep slopes and over forested and grassland cover types. Condor flight behavior was temporally predictable, and birds flew lower and closer to the rotor-swept zone during early morning and evening hours and during the winter months, when thermal updrafts were weakest. Although Condors only occasionally flew at altitudes that placed them in the rotor-swept zone of turbines, they regu...
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Terrestrial Scavenging of Marine Mammals: Cross-Ecosystem Contaminant Transfer and Potential Risks to Endangered California Condors (Gymnogyps Californianus)
2016Co-Authors: Carolyn M. Kurle, Joseph Brandt, Joe Burnett, Victoria J. Bakker, Jennie Jones Scherbinski, Holly Copeland, Myra E. FinkelsteinAbstract:The critically endangered California Condor (Gymnogyps Californianus) has relied intermittently on dead-stranded marine mammals since the Pleistocene, and this food source is considered important for their current recovery. However, contemporary marine mammals contain persistent organic pollutants that could threaten Condor health. We used stable carbon and nitrogen isotope, contaminant, and behavioral data in coastal versus noncoastal Condors to quantify contaminant transfer from marine mammals and created simulation models to predict the risk of reproductive impairment for Condors from exposure to DDE (p,p′-DDE), a major metabolite of the chlorinated pesticide DDT. Coastal Condors had higher whole blood isotope values and mean concentrations of contaminants associated with marine mammals, including mercury (whole blood), sum chlorinated pesticides (comprised of ∼95% DDE) (plasma), sum polychlorinated biphenyls (PCBs) (plasma), and sum polybrominated diphenyl ethers (PBDEs) (plasma), 12–100-fold greater than those of noncoastal Condors. The mean plasma DDE concentration for coastal Condors was 500 ± 670 (standard deviation) (n = 22) versus 24 ± 24 (standard deviation) (n = 8) ng/g of wet weight for noncoastal Condors, and simulations predicted ∼40% of breeding-age coastal Condors have DDE levels associated with eggshell thinning in other avian species. Our analyses demonstrate potentially harmful levels of marine contaminant transfer to California Condors, which could hinder the recovery of this terrestrial species
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Lead Exposure Risk from Trash Ingestion by the Endangered California Condor (Gymnogyps Californianus)
Journal of wildlife diseases, 2015Co-Authors: Myra E. Finkelstein, Joseph Brandt, Jesse Grantham, Estelle A. Sandhaus, Allan Mee, Patricia Jill Schuppert, Donald R. SmithAbstract:Abstract Lead poisoning from ingestion of spent lead ammunition is one of the greatest threats to the recovery of California Condors (Gymnogyps Californianus) in the wild. Trash ingestion by Condors is well documented, yet the extent that trash presents a lead exposure risk is unknown. We evaluated 1,413 trash items collected from Condor nest areas and nestlings in the Transverse Range of Ventura County, California, US, from 2002 to 2008, for their potential as a lead exposure risk to Condors. We visually identified 71 items suspected to contain sufficient lead to be of toxicologic concern. These items were leached with weak acid and analyzed for lead. Twenty-seven of the 71 leached items (~2% of the 1,413 items) were “lead containing” based on criteria of a leachate lead concentration >1 μg/mL, with the majority of these items (22; 81% of the 27 lead items) being ammunition related (e.g., spent bullet casings and jacketed bullets). Only three of the 1,413 items collected were lead containing but were cle...
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Two decades of cumulative impacts to survivorship of endangered California Condors in California
Biological Conservation, 2015Co-Authors: Terra R. Kelly, Bruce A. Rideout, L. Joseph Burnett, Joseph Brandt, Daniel George, Jesse Grantham, Alacia Welch, Kelly J. Sorenson, David Moen, James RasicoAbstract:Abstract We investigated threats to the California Condor (Gymnogyps Californianus), a flagship endangered species, using individual data on survival during a 20 year period of intensive recovery efforts. Over the two decades of reintroductions, Condors in California had an estimated median survival time of 7.8 years suggesting that 50% of Condors are expected to survive in the wild long enough to contribute to recruitment. In general, annual mortality rates exceeded levels necessary for a stable population; however, mortality declined, reaching levels needed for population stability, during the second decade of re-establishment. Intensive management practices, including utility pole aversion training and clinical interventions to prevent lead-related deaths likely contributed to the decrease in mortality rates. Utility line collision and/or electrocution was an important factor causing mortality over the two decades; though, this threat has largely been mitigated through management and targeted efforts in high-risk areas. In the past, wildfires were not considered a major threat to survival of free-flying Condors. However, our analyses suggest that forest fires are significantly linked to the hazard of death, and increased wildfire activity in California highlights this population's vulnerability to catastrophic losses from forest fire. Lead poisoning, which was a major driver in the population's decline, was a leading cause of death accounting for the greatest adult mortality, and lead exposure remains the most significant threat. Recent lead ammunition reduction efforts in the Condor range in California hold promise for improving the recovery potential for this population.
Myra E. Finkelstein - One of the best experts on this subject based on the ideXlab platform.
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Measuring Handling Stress at Multiple Time Scales in the Chronically Lead-exposed California Condor
2016Co-Authors: Zeka Kuspa, Christopher W. Tubbs, Don R Smith, Myra E. FinkelsteinAbstract:Measuring Handling Stress at Multiple Time Scales in the Chronically Lead-exposed California Condor UCSC California Condor Conservation Research Program Saving Species with Science Z Kuspa 1 , C Tubbs 2 , D R Smith 1 , and M Finkelstein 1 1 Department of Microbiology and Environmental Toxicology, University of California, Santa Cruz, CA 2 Institute for Conservation Research, San Diego Zoo Global Introduction Study Objectives Why study stress in California Condors? • Altered stress responses can reduce avian reproduction and survival. 1. Evaluate precision and accuracy of immunoassay methods for measurement of corticosterone and corticosterone metabolite concentrations in California Condor plasma, urates, and feathers + lead California Condors are chronically lead exposed from ingesting lead- based ammunition in their food sources. 60 – 70% of wild Condors experience subclinical lead exposure while 20 - 30% require clinical treatment per year. • Lead exposure elevates levels of glucocorticoid stress hormones (GCs) released in response to a stressor. Hypothalamus Anterior Pituitary ACTH ↑GCs 3. Validate experimental stressor for comparing stress responses between individual Condors Sample Collection for Biological Validation of Method Methods Hormone Measurement Primary GC in birds: Corticosterone* Kits Tested: Two immunoassays optimized to measure corticosterone in plasma 1) Enzyme-linked Immunoassay (ELISA) (Enzo Life Sciences) 2) Radioimmunoassay (RIA) (MP Biomedicals) ELISA RIA Matrix compounds can interfere w/ Ab-CORT binding polyclonal Ab polyclonal Ab raised in raised in rabbits sheep Method Validation 1. Matrix/dilution effects: Protein breakdown, fat deposition, inhibition of reproductive hormone pathway 2X 4X 2. Precision: 3. Accuracy: Samples are collected opportunistically during a health check: 1) Trap Condor by hoop net 2) Restrain Condor (15-30 minutes) 3) Kennel (1-6 hours) for urate sampling. Collect urate at ~15 min. intervals. Urate corticosterone metabolite concentrations stable 30 minutes before freezing. 8X 16X 32X 1X Pooled plasma or sample extract run in triplicate *and corticosterone metabolites in urates 1. Corticosterone measurements by RIA more consistent across sample type and sample dilution range than ELISA Peak Plasma Baseline Results My results highlight the need to validate immunoassays for novel sample types Capture and handling elicits an increase in corticosterone release, measureable in urates and feathers Corticosterone responses to capture and handling stressor varies widely among individual Condors (2-11 fold over baseline) Next Steps: Determine lead effect on stress response in Condors with different lead exposure histories 2 cm Urates Time since handling start (minutes) Duration 24 hr 48 hr Time after stressor 5. Urates from 7 Condors show significant increase in Measurable increases in CORT over first 2.5 and hours since handling start for all Condors tested corticosterone metabolites after capture handling stressor (p=0.0026). Additionally corticosterone stress responses variable among individual Condors. Corticosterone (% of first sample) Stressor 6. Feather grown during capture and handling stressor has higher corticosterone concentration than feather grown before stressor 4. Plasma corticosterone values vary among individual Condors tested but does not appear related to time after handling start Corticosterone (ng/mL) [Glucocorticoid] • Measuring GC metabolites in urates and feather allows for non-invasive measurement of baseline GC concentrations in a wild Condors, as well as quantifying stress at multiple time scales: 12 hr Both RIA and ELISA return accurate and precise corticosterone measurements for Condor plasma Spike Recovery Known quantity of corticosterone Serial dilution • Measuring baseline (pre-stress) levels of GCs in plasma is not feasible in wild species. 2 hr 2. Biologically validate method for detecting changes in corticosterone release in a live Condor Target Cells Why are multiple sample types necessary to assess Condor stress response? 1 hr RIA better suited for measurement and comparison of corticosterone and corticosterone metabolites across all sample types in study: plasma, urates, and feather CRH Adrenal Cortex • The stress induced by frequent trapping and handling of California Condors as well as the clinical management for lead poisoning is unknown. 3 min Stress 2 cm 2. Both methods perform well for Condor plasma, but RIA more reliable than ELISA for urate and feather Condor primary feathers: Growth rate ~0.5 cm/day. [GC] of 2cm feather sections represent 4-5 day integration of plasma hormone levels. Why is careful validation of existing hormone measurement methods necessary for Condor samples? • The hormonal stress response varies between species in magnitude, duration, and dominant stress hormones. Hormone metabolism and sample matrix is also species-specific. • Thus, we must first validate a hormone measurement method for Condors before we can assess the interactions of lead poisoning and clinical management (e.g., capture and handling) on the stress response. 3. Different methods will yield different corticosterone* levels in the same samples *and corticosterone metabolites (CORTm) in urates ELISA RIA Urates Plasma Feather Est. Feather Growth Days Col 23 Col 23 Col 23 Col 23 Col 23 Col 23 Col 23 vs vs vs vs vs vs vs Feathers from Condors 312 and 336. Red arrows indicate size and location of sections on primary feather. Red shading indicates estimated time of handling event. Each section represents 4-5 days of feather growth. Col 15 Col 15 Col 15 Col 15 Col 15 Col 15 Col 15 Acknowledgements Time since handling start (minutes) Magnitude of measured corticosterone metabolites excreted in response to stressor across avian species Species Golden Eagle (Aquila chrysaetos) Greater Rhea (Rhea americana) Budgerigar (Melopsittacus undulatus) California Condor (Gymnogyps Californianus) Time since handling start CORT or CORTm (ng/mL plasma, ng/g urate and feather) • Most immunoassay kits are optimized for use with plasma only, although they advertise kit compatibility with other biological fluids. Urate CORTm (ng/g wet wt.) ng CORT/g feather Conclusions Average corticosterone* peak (% baseline) Method Stressor Tissue Sample Saline Injection feces Saline Injection feces Saline Injection Capture and restraint Authors Year RIA Staley et al. RIA Leche et al. feces RIA Young and Hallford urates RIA Kuspa et al. unpub. We would like to acknowledge the Los Angeles Zoo Condor keepers and the field staff at Pinnacles National Park and Ventana Wildlife Society for their help with sample collection. Without them this study would not be possible. We would also like to thank Dr. Christopher Tubbs and Alan Fetter from the San Diego Zoo for providing lab space, RIA expertise, and mentorship. Thanks also to the UCSC METX department and members of the Smith lab who provided their help and technical support.
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Terrestrial Scavenging of Marine Mammals: Cross-Ecosystem Contaminant Transfer and Potential Risks to Endangered California Condors (Gymnogyps Californianus)
2016Co-Authors: Carolyn M. Kurle, Joseph Brandt, Joe Burnett, Victoria J. Bakker, Jennie Jones Scherbinski, Holly Copeland, Myra E. FinkelsteinAbstract:The critically endangered California Condor (Gymnogyps Californianus) has relied intermittently on dead-stranded marine mammals since the Pleistocene, and this food source is considered important for their current recovery. However, contemporary marine mammals contain persistent organic pollutants that could threaten Condor health. We used stable carbon and nitrogen isotope, contaminant, and behavioral data in coastal versus noncoastal Condors to quantify contaminant transfer from marine mammals and created simulation models to predict the risk of reproductive impairment for Condors from exposure to DDE (p,p′-DDE), a major metabolite of the chlorinated pesticide DDT. Coastal Condors had higher whole blood isotope values and mean concentrations of contaminants associated with marine mammals, including mercury (whole blood), sum chlorinated pesticides (comprised of ∼95% DDE) (plasma), sum polychlorinated biphenyls (PCBs) (plasma), and sum polybrominated diphenyl ethers (PBDEs) (plasma), 12–100-fold greater than those of noncoastal Condors. The mean plasma DDE concentration for coastal Condors was 500 ± 670 (standard deviation) (n = 22) versus 24 ± 24 (standard deviation) (n = 8) ng/g of wet weight for noncoastal Condors, and simulations predicted ∼40% of breeding-age coastal Condors have DDE levels associated with eggshell thinning in other avian species. Our analyses demonstrate potentially harmful levels of marine contaminant transfer to California Condors, which could hinder the recovery of this terrestrial species
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Lead Exposure Risk from Trash Ingestion by the Endangered California Condor (Gymnogyps Californianus)
Journal of wildlife diseases, 2015Co-Authors: Myra E. Finkelstein, Joseph Brandt, Jesse Grantham, Estelle A. Sandhaus, Allan Mee, Patricia Jill Schuppert, Donald R. SmithAbstract:Abstract Lead poisoning from ingestion of spent lead ammunition is one of the greatest threats to the recovery of California Condors (Gymnogyps Californianus) in the wild. Trash ingestion by Condors is well documented, yet the extent that trash presents a lead exposure risk is unknown. We evaluated 1,413 trash items collected from Condor nest areas and nestlings in the Transverse Range of Ventura County, California, US, from 2002 to 2008, for their potential as a lead exposure risk to Condors. We visually identified 71 items suspected to contain sufficient lead to be of toxicologic concern. These items were leached with weak acid and analyzed for lead. Twenty-seven of the 71 leached items (~2% of the 1,413 items) were “lead containing” based on criteria of a leachate lead concentration >1 μg/mL, with the majority of these items (22; 81% of the 27 lead items) being ammunition related (e.g., spent bullet casings and jacketed bullets). Only three of the 1,413 items collected were lead containing but were cle...
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Linking cases of illegal shootings of the endangered California Condor using stable lead isotope analysis.
Environmental research, 2014Co-Authors: Myra E. Finkelstein, Zeka Kuspa, Alacia Welch, Curtis Eng, Michael Clark, Joseph Burnett, Donald R. SmithAbstract: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.
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Discrimination Factors for Stable Isotopes of Carbon and Nitrogen in Blood and Feathers from Chicks and Juveniles of the California Condor
The Condor, 2013Co-Authors: Carolyn M. Kurle, Daniel George, Myra E. Finkelstein, Kimberly R. Smith, Debbie Ciani, Paul L. Koch, Donald R. SmithAbstract:Abstract. Stable-isotope ratios of carbon (13C/12C; δ13C) and nitrogen (15N/14N; δ15N) in animal tissues are analyzed to estimate animal foraging ecology because these ratios reflect those of an animal's diet. This reflection is generally indirect, as stable-isotope ratios change with trophic level. These differences, called discrimination factors (reported as Δ), vary considerably by species and tissue. Variations in discrimination factors used in stableisotope mixing models can lead to inaccurate estimates of diets. Therefore, determining accurate discrimination factors specific to species and tissue is important. We established the Δ13C and Δ15N values between diet and blood and feathers from chicks and juveniles of the California Condor (Gymnogyps Californianus). Hatchlings were fed rats for 76–119 days, whereas juveniles were fed dairy calves for 64 days. The mean Δ13C and Δ15N values (± SD) between chick feathers and rat muscle were 0.4 ± 0.4‰ and 3.1 ± 0.2‰, respectively; those between chicks' whol...
