Now showing items 1-20 of 836

    • Proactive conservation management of an island-endemic bird species in the face of global change

      Morrison, Scott A.; Sillett, T. Scott; Ghalambor, Cameron K.; Fitzpatrick, John W.; Graber, David M.; Bakker, Victoria J.; Bowman, Reed; Collins, Charles T.; Collins, Paul W.; Delaney, Kathleen Semple; et al. (2011)
      Here, we discuss conservation management of the island scrub-jay (Aphelocoma insularis), the only island-endemic passerine species in the continental United States, which is currently restricted to 250-square-kilometer Santa Cruz Island, California. Although the species is not listed as threatened by state or federal agencies, its viability is nonetheless threatened on multiple fronts. We discuss management actions that could reduce extinction risk, including vaccination, captive propagation, biosecurity measures, and establishing a second free-living population on a neighboring island....
    • Turtles in trouble: The world's 25+ most endangered tortoises and freshwater turtles–2011

      IUCN/SSC Tortoise and Freshwater Turtle Specialist Group; Turtle Conservation Fund; Turtle Survival Alliance; Turtle Conservancy; Chelonian Research Foundation; Conservation International; Wildlife Conservation Society; San Diego Zoo Global; Rhodin, A.G.J.; Walde, A.D.; et al. (IUCN/SSC Tortoise and Freshwater Turtle Specialist Group, c/o Chelonian Research FoundationLunenburg, MA, 2011)
      As part of a comprehensive strategy to highlight and help prioritize urgently needed conservation action for the most critically endangered turtles and tortoises in the world, the Turtle Conservation Coalition have highlighted the Top 25 most endangered species every four years since 2003. In this third installment, more than 25 species are covered and the information presented was provided by the coalition rather than solely by one or two organizations. In general, this document includes all terrestrial and freshwater turtles and tortoises currently ranked as Extinct in the Wild or Critically Endangered on the current 2010 IUCN Red List, or provisionally so, based on recent draft assessments by the TFTSG (Turtle Taxonomy Working Group 2010) carried out in a series of turtle-focused IUCN Red Listing workshops held around the world. In addition, included on this list are a few species at lesser Red List categories that are also considered to be at a high risk of extinction.
    • Molecular phylogeny and evolution of the Perissodactyla

      Steiner, Cynthia C.; Ryder, Oliver A. (2011)
      The evolution of perissodactyls (rhinoceroses, tapirs, and horses) has been well studied primarily because of their extensive fossil record. Nevertheless, controversy persists regarding relationships of some of the extant taxa, reflecting inconsistencies between molecular and morphological studies. Here we examine the phylogenetic relationships of 16 living perissodactyl species by concatenating two mitochondrial and nine nuclear genes, and we estimate their divergence times using a relaxed Bayesian molecular clock approach....
    • Unexpected shallow genetic divergence in Turks Island boas (Epicrates c. chrysogaster) reveals single evolutionarily significant unit for conservation

      Reynolds, R.G.; Gerber, Glenn P.; Fitzpatrick, B.M. (2011)
      ... The subspecies has likely been extirpated from several islands in its historic range, and all remaining populations are threatened with extirpation owing to habitat loss, introduced feral predators, malicious killing, and vehicle strikes. To assist conservation efforts, we undertook a genetic analysis of 53 individual E. c. chrysogaster, representing five island populations, with the goal of identifying existing population structure and genetic diversity. For each snake sampled, we sequenced one mitochondrial and two nuclear genes, resulting in 1591 bp of sequence, and screened nine microsatellite loci....
    • Behavioral audiogram of the giant panda (Ailuropoda melanoleuca): Preliminary results

      Owen, Megan A.; Keating, Jennifer L.; Denes, Samuel L.; Hawk, Kathy; Boroski, Juli; Fiore, Angela; Swaisgood, Ronald R. (2011)
      We used behavioral techniques to assess the hearing sensitivity of four, critically endangered, giant pandas at the San Diego Zoo. Study subjects included one adult male (age 19), two adult females (ages 5 and 19), and one sub-adult female (age 3)…. Hearing sensitivity data will enhance the understanding of how anthropogenic noise may impact both free-ranging and captive giant pandas.
    • Twenty-nine polymorphic microsatellite loci in Cyclura carinata, the Turks and Caicos Iguana, a critically endangered island endemic

      Welch, M.E.; Long, G.J.; Berk, J.W.; Getz, A.H.; Gerber, Glenn P.; Wallace, L.E. (2011)
      Cyclura carinata, a critically endangered Caribbean rock iguana, now occupies less than 5% of its historic range. Remaining populations are genetically structured, but available tools are insufficient to identify taxonomic units. Ten polymorphic microsatellites isolated from C. carinata, and 19 loci developed for congeners are identified....
    • Conservation of amphibians and reptiles in the British Virgin Islands: status and patterns

      Perry, G.; Gerber, Glenn P.; Hailey, A.; Wilson, B.S.; Horrocks, J. (Brill Academic PublishersLeiden, The Netherlands, 2011)
      ...Invasive species are still arriving, establishing, and spreading. Thus, although the short-term conservation status of the BVI herpetofauna appears unlikely to change, we are more concerned about the mid-term outlook. We recommend some specific remedies intended to offset these pressures and provide long-term protection to the biota of the BVI
    • Reconnecting People to Nature Is a Prerequisite for the Future Conservation Agenda: Response from Swaisgood and Sheppard

      Swaisgood, Ronald R.; Sheppard, James (2011)
      ...Our point is not that hope is the logical alternative but that it is the necessary alternative—for if we extrapolate the legion scenarios of despair to their conclusion then we are merely fighting with time over an inevitably bleak future. Empirical research by conservation psychologists tells us that if we do not find reason for hope, motivation will falter, and so will conservation action....
    • TSA India Program expanding to include five turtle priority areas: Coverage to include all endemic and endangered Chelonians

      Singh, S.; Horne, Brian D. (2011)
      India is a tortoise and freshwater turtle diversity hotspot, ranking at the top in importance for turtle conservation in Asia. With 28 species, India’s diversity ranks sixth globally and is tied with Colombia and Vietnam....
    • On the phylogeny of Mustelidae subfamilies: analysis of seventeen nuclear non-coding loci and mitochondrial complete genomes

      Yu, Li; Peng, Dan; Liu, Jiang; Luan, Pengtao; Liang, Lu; Lee, Hang; Lee, Muyeong; Ryder, Oliver A.; Zhang, Yaping (2011)
      Background Mustelidae, as the largest and most-diverse family of order Carnivora, comprises eight subfamilies. Phylogenetic relationships among these Mustelidae subfamilies remain argumentative subjects in recent years. One of the main reasons is that the mustelids represent a typical example of rapid evolutionary radiation and recent speciation event. Prior investigation has been concentrated on the application of different mitochondrial (mt) sequence and nuclear protein-coding data, herein we employ 17 nuclear non-coding loci (>15 kb), in conjunction with mt complete genome data (>16 kb), to clarify these enigmatic problems. Results The combined nuclear intron and mt genome analyses both robustly support that Taxidiinae diverged first, followed by Melinae. Lutrinae and Mustelinae are grouped together in all analyses with strong supports. The position of Helictidinae, however, is enigmatic because the mt genome analysis places it to the clade uniting Lutrinae and Mustelinae, whereas the nuclear intron analysis favores a novel view supporting a closer relationship of Helictidinae to Martinae. This finding emphasizes a need to add more data and include more taxa to resolve this problem. In addition, the molecular dating provides insights into the time scale of the origin and diversification of the Mustelidae subfamilies. Finally, the phylogenetic performances and limits of nuclear introns and mt genes are discussed in the context of Mustelidae phylogeny. Conclusion Our study not only brings new perspectives on the previously obscured phylogenetic relationships among Mustelidae subfamilies, but also provides another example demonstrating the effectiveness of nuclear non-coding loci for reconstructing evolutionary histories in a group that has undergone rapid bursts of speciation.
    • 117 Cryopreservation of snake semen: Are we frozen in time?

      Zacariotti, R.; Guimarães, M.; Jensen, Thomas; Durrant, Barbara S. (2011)
      The increasing number of endangered snake species, isolation of small fragmented populations with associated inbreeding and mating or conception problems in captivity underscore the need to develop assisted reproductive techniques such as semen cryopreservation and artificial insemination to enhance conservation efforts. However, no efficient protocols for semen evaluation, cooling, or freezing are described in the 4 known publications on snake semen cryopreservation. In this initial study, semen was collected noninvasively from 4 live adult red diamond rattlesnakes (Crotalus ruber) by ventral massage....
    • Herpesvirus surveillance and discovery in zoo-housed ruminants

      Partin, Teagen G.; Schrenzel, Mark D.; Braun, Josephine; Witte, Carmel L.; Kubiski, Steven V.; Lee, Justin; Rideout, Bruce (Public Library of Science (PLoS), 2021)
      Gammaherpesvirus infections are ubiquitous in captive and free-ranging ruminants and are associated with a variety of clinical diseases ranging from subclinical or mild inflammatory syndromes to fatal diseases such as malignant catarrhal fever. Gammaherpesvirus infections have been fully characterized in only a few ruminant species, and the overall diversity, host range, and biologic effects of most are not known. This study investigated the presence and host distribution of gammaherpesviruses in ruminant species at two facilities, the San Diego Zoo and San Diego Zoo Safari Park. We tested antemortem (blood, nasal or oropharyngeal swabs) or postmortem (internal organs) samples from 715 healthy or diseased ruminants representing 96 species and subspecies, using a consensus-based herpesvirus PCR for a segment of the DNA polymerase (DPOL) gene. Among the 715 animals tested, 161 (22.5%) were PCR and sequencing positive for herpesvirus, while only 11 (6.83%) of the PCR positive animals showed clinical signs of malignant catarrhal fever. Forty-four DPOL genotypes were identified of which only 10 have been reported in GenBank. The data describe viral diversity within species and individuals, identify host ranges of potential new viruses, and address the proclivity and consequences of interspecies transmission during management practices in zoological parks. The discovery of new viruses with wide host ranges and presence of co-infection within individual animals also suggest that the evolutionary processes influencing Gammaherpesvirus diversity are more complex than previously recognized.
    • Using microsatellite diversity in wild Anegada iguanas (Cyclura pinguis) to establish relatedness in a captive breeding group of this critically endangered species

      Mitchell, A.A.; Lau, J.; Chemnick, Leona G.; Thompson, E. A.; Alberts, Allison C.; Ryder, Oliver A.; Gerber, Glenn P. (2011)
      Awareness of the genealogical relationships between founder animals in captive breeding programs is essential for the selection of mating pairs that maintain genetic diversity. If captive founder relationships are unknown they can be inferred using genetic data from wild populations. Here, we report the results of such an analysis for six Cyclura pinguis (Sauria: Iguanidae) acquired as adults in 1999 by the San Diego Zoo Institute for Conservation Research to begin a captive breeding program for this critically endangered species....
    • The effects of education programs on Atlantic bottlenose dolphin (Tursiops truncatus) behavior

      Miller, Lance J.; Mellen, J.; Greer, T.; Kuczaj, S.A. (2011)
      ...The present study examined the short-term effects of dolphin shows and interaction programmes on the behaviour of Atlantic bottlenose dolphins at six facilities. Rates of affiliative behaviour, aggressive behaviour, repetitive behaviour and percentage of time spent socialising were found to be unrelated to dolphin shows or interaction programmes....
    • Hormones and reproductive cycles in Crocodilians

      Milnes, Matthew R.; Norris, D.O.; Lopez, K.H. (ElsevierSan Diego, CA, 2011)
      During embryonic development, hormonal influence upon sexual differentiation in crocodilians begins and continues for years until sexual maturation is attained. Shortly after sex determination, estrogen production in the embryonic ovary increases and promotes proliferation of the Müsllerian ducts, whereas the testis produces anti-Müllerian hormone, which results in its regression....
    • Stereotypic behavior in wild marine carnivores?

      Miller, Lance J.; Kuczaj, S.; Herzing, D. (2011)
      ...The following commentary details the observations of wild lemon sharks (Negaprion brevirostris) engaging in a stereotyped swimming pattern behind a research vessel north of Grand Bahama Island, Bahamas. We consider a possible explanation for the sharks' behavior and hope to stimulate conversation as well as increase examination of animal management routines in zoological facilities.
    • Impacts of the Cretaceous Terrestrial Revolution and KPg extinction on mammal diversification

      Meredith, R.W.; Janecka, J.E.; Gatesy, J.; Ryder, Oliver A.; Fisher, C.A.; Teeling, E.C.; Goodbla, A.; Eizirik, E.; Simao, T.L.L.; Stadler, T.; et al. (2011)
      ...We constructed a molecular supermatrix for mammalian families and analyzed these data with likelihood-based methods and relaxed molecular clocks. Phylogenetic analyses resulted in a robust phylogeny with better resolution than phylogenies from supertree methods....
    • Altered gonadal expression of TGF-beta superfamily signaling factors in environmental contaminant-exposed juvenile alligators

      Moore, B.C.; Milnes, Matthew R.; Kohno, S.; Katsu, Y.; Iguchi, T. (2011)
      Environmental contaminant exposure can influence gonadal steroid signaling milieus; however, little research has investigated the vulnerability of non-steroidal signaling pathways in the gonads. Here we use American alligators (Alligator mississippiensis) hatched from field-collected eggs to analyze gonadal mRNA transcript levels of the activin–inhibin–follistatin gene expression network and growth differentiation factor 9....
    • Demographic effects of legal timber harvesting on Guaiacum sanctum L., an endangered neotropical tree: implications for conservation

      López-Toledo, Leonel; Murillo-García, A.; Martínez-Ramos, M.; Pérez-Salicrup, D. (2011)
      Guaiacum sanctum is a timber tree species from the Americas, considered threatened in eleven different countries, including Mexico, and listed in CITES Appendix II. This species is currently harvested legally in the southern Mexican state of Campeche. Despite its protected status, the current condition of its populations and the effects of harvesting upon them have not been assessed. The conservation status of four unlogged populations were evaluated across Central Campeche by documenting their densities and demographic structures, and then compared the size class demographic structures of one unlogged and three logged populations at different times after harvest (3, 8 and 20 years) to evaluate the effects of timber harvesting upon population structure. Additionally, a regeneration index (proportion of seedlings within the population) was estimated for each of the seven populations. Densities of G. sanctum varied from 278 to 1732 stems/ha with ≥1cm at 1.3m·height in Campeche. Differences were found in the population structures of unlogged populations, although the density of seedlings and trees was high in all of the sites. Contrary to expectations, higher densities were found in all size classes in logged populations. Results suggest that current logging practices do not have a drastic negative effect on the density of remaining individuals. Although the results indicate that G. sanctum in Campeche is not locally endangered, it is recommend that it be maintained in CITES Appendix II.
    • Distribution and population patterns of the threatened palm Brahea aculeata in a tropical dry forest in Sonora, Mexico

      López-Toledo, Leonel; Horn, Christa M.; Endress, Bryan A. (2011)
      The use of non-timber forest products (NTFPs) has great potential for the conservation of natural resources and rural development…. However, in most cases basic ecological information, such as distribution and abundance of the species is unknown, as is information on the ecological implications of human impacts, such as leaf harvest and livestock grazing…. Results from this study will be used to develop appropriate conservation, management and restoration plans of B. aculeata in the area.