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Recent Submissions

  • Climate change and landscape-use patterns influence recent past distribution of giant pandas

    Tang, Junfeng; Swaisgood, Ronald R.; Owen, Megan A.; Zhao, Xuzhe; Wei, Wei; Pilfold, Nicholas W.; Wei, Fuwen; Yang, Xuyu; Gu, Xiaodong; Yang, Zhisong; et al. (The Royal Society, 2020)
    Climate change is one of the most pervasive threats to biodiversity globally, yet the influence of climate relative to other drivers of species depletion and range contraction remain difficult to disentangle.... We conclude that the panda's distribution has been influenced by changing climate, but conservation intervention to manage habitat is working to increasingly offset these negative consequences.
  • Allen Cays Rock Iguana, Cyclura cychlura ssp. inornata. IUCN Red List of Threatened Species

    Iverson, John; Grant, Tandora D.; Buckner, Sandra (IUCN, 2019)
    Only two natural breeding subpopulations of the Allen Cays Rock Iguana have ever been known (U and Leaf Cays), with a combined population of less than 500 mature animals inhabiting only seven total hectares (0.07 km2). Those two subpopulations have recovered from near extinction in the early 1900s to current levels that are near the limit of the resources available on those two cays (carrying capacity). Human-assisted translocations to other Bahamian islands over the past two decades has decreased the number of large adults on the source cays, and although these moves have increased the number of subpopulations, without reproduction almost all are considered not viable....
  • Population Analysis & Breeding and Transfer Plan, Grand Cayman Blue Iguana (Cyclura lewisi), AZA Species Survival Plan Yellow Program

    Grant, Tandora D.; Ivy, Jamie A. (Population Management Center. Associaton of Zoos and Aquariums, Lincoln Park Zoo, San Diego Zoo Global, 2020)
  • Grand Cayman Blue Iguana (Cyclura lewisi) AZA Animal Program Population Viability Analysis Report.

    Mechak, L.; Grant, Tandora D.; Krebs, J. (Associaton of Zoos and Aquariums, 2015)
  • Jamaican Iguana (Cyclura collei) AZA Animal Program Population Viability Analysis Report.

    Mechak, L.; Grant, Tandora D.; Krebs, J. (Associaton of Zoos and Aquariums, 2015)
  • Jamaican Iguana (Cyclura collei) AZA Regional Studbook. AZA Yellow SSP Program.

    Grant, Tandora D. (Associaton of Zoos and Aquariums, 2017)
  • Rapid response to evaluate the presence of amphibian chytrid fungus (Batrachochytrium dendrobatidis) and ranavirus in wild amphibian populations in Madagascar

    Kolby, Jonathan E.; Smith, Kristine M.; Ramirez, Sara D.; Rabemananjara, Falitiana; Pessier, Allan P.; Brunner, Jesse L.; Goldberg, Caren S.; Berger, Lee; Skerratt, Lee F. (2015)
    We performed a rapid response investigation to evaluate the presence and distribution of amphibian pathogens in Madagascar following our identification of amphibian chytrid fungus (Batrachochytrium dendrobatidis, Bd) and ranavirus in commercially exported amphibians. This targeted risk-based field surveillance program was conducted from February to April 2014 encompassing 12 regions and 47 survey sites. We simultaneously collected amphibian and environmental samples to increase survey sensitivity and performed sampling both in wilderness areas and commercial amphibian trade facilities. Bd was not detected in any of 508 amphibian skin swabs or 68 water filter samples, suggesting pathogen prevalence was below 0.8%, with 95% confidence during our visit. Ranavirus was detected in 5 of 97 amphibians, including one adult Mantidactylus cowanii and three unidentified larvae from Ranomafana National Park, and one adult Mantidactylus mocquardi from Ankaratra. Ranavirus was also detected in water samples collected from two commercial amphibian export facilities. We also provide the first report of an amphibian mass-mortality event observed in wild amphibians in Madagascar. Although neither Bd nor ranavirus appeared widespread in Madagascar during this investigation, additional health surveys are required to disentangle potential seasonal variations in pathogen abundance and detectability from actual changes in pathogen distribution and rates of spread. Accordingly, our results should be conservatively interpreted until a comparable survey effort during winter months has been performed. It is imperative that biosecurity practices be immediately adopted to limit the unintentional increased spread of disease through the movement of contaminated equipment or direct disposal of contaminated material from wildlife trade facilities. The presence of potentially introduced strains of ranaviruses suggests that Madagascar's reptile species might also be threatened by disease. Standardized population monitoring of key amphibian and reptile species should be established with urgency to enable early detection of potential impacts of disease emergence in this global biodiversity hotspot.
  • Early 1900s Detection of Batrachochytrium dendrobatidis in Korean Amphibians

    Fong, Jonathan J.; Cheng, Tina L.; Bataille, Arnaud; Pessier, Allan P.; Waldman, Bruce; Vredenburg, Vance T. (2015)
    The pathogenic fungus Batrachochytrium dendrobatidis (Bd) is a major conservation concern because of its role in decimating amphibian populations worldwide. We used quantitative PCR to screen 244 museum specimens from the Korean Peninsula, collected between 1911 and 2004, for the presence of Bd to gain insight into its history in Asia. Three specimens of Rugosa emeljanovi (previously Rana or Glandirana rugosa), collected in 1911 from Wonsan, North Korea, tested positive for Bd. Histology of these positive specimens revealed mild hyperkeratosis – a non-specific host response commonly found in Bd-infected frogs – but no Bd zoospores or zoosporangia. Our results indicate that Bd was present in Korea more than 100 years ago, consistent with hypotheses suggesting that Korean amphibians may be infected by endemic Asian Bd strains.
  • Efectos del manejo tradicional sobre la palma Brahea aculeata en una selva seca del sur de Sonora, México

    López-Toledo, Leonel; Espinosa-Hidalgo, Carlos; Horn, Christa M.; Endress, Bryan A. (2015)
    En este estudio se evaluaron los efectos del manejo tradicional de Brahea aculeata (Arecaceae), sobre algunos atributos funcionales (hojas totales, producción y tamaño de hojas) y demográficos (mortalidad, crecimiento y reproducción). Las hojas de la especie son utilizadas para techos de casas y artesanías; y debido al pastoreo libre de ganado vacuno en el bosque, la especie puede sufrir herbivoría. Para evaluar los efectos del pastoreo y la cosecha de hojas se estableció un experimento en la Reserva “Sierra de Álamos”, Sonora, México, en el que se simularon las diferentes prácticas del manejo tradicional. Se establecieron seis tratamientos que combinan el pastoreo (con/sin) e intensidades de cosecha (sin cosecha/baja/intensiva). En general, en palmas pequeñas (≤ 200 cm de largo de tallo), se encontraron efectos interactivos del pastoreo y la cosecha de hojas, mientras que en palmas grandes (> 200 cm) únicamente para la cosecha. En palmas pequeñas se encontraron efectos negativos en el número y tamaño de hojas; mientras que la producción de hojas, la mortalidad y el crecimiento, el efecto fue positivo. Para palmas grandes, el efecto fue positivo en todos los casos; excepto en la mortalidad, en los que no se encontraron efectos. Los efectos positivos se podrían explicar como una respuesta sobrecompensatoria en la que la pérdida de área foliar se puede suplir mediante la alteración de procesos relacionados con la fotosíntesis y/o la asignación de recursos. Este estudio contribuye con información útil para el establecimiento de un programa de manejo, basado en el aprovechamiento tradicional de la especie en el área.
  • Seroepidemiologic survey of potential pathogens in obligate and facultative scavenging avian species in California

    Straub, Mary H.; Kelly, Terra R.; Rideout, Bruce; Eng, Curtis; Wynne, Janna; Braun, Josephine; Johnson, Christine K. (2015)
    Throughout the world, populations of scavenger birds are declining rapidly with some populations already on the brink of extinction. Much of the current research into the factors contributing to these declines has focused on exposure to drug residues, lead, and other toxins. Despite increased monitoring of these declining populations, little is known about infectious diseases affecting scavenger bird species. To assess potential infectious disease risks to both obligate and facultative scavenger bird species, we performed a serosurvey for eleven potential pathogens in three species of scavenging birds in California: the California condor (Gymnogyps californianus), turkey vulture (Cathartes aura) and golden eagle (Aquila chrysaetos). California condors were seropositive for avian adenovirus, infectious bronchitis virus, Mycoplasma gallisepticum, avian paramyxovirus-2, West Nile virus (WNV) and Toxoplasma gondii. Golden eagles were seropositive for avian adenovirus, Chlamydophila psittaci and Toxoplasma gondii, and turkey vultures were seropositive for avian adenovirus, Chlamydophila psittaci, avian paramyxovirus-1, Toxoplasma gondii and WNV. Risk factor analyses indicated that rearing site and original release location were significantly associated with a positive serologic titer to WNV among free-flying condors. This study provides preliminary baseline data on infectious disease exposure in these populations for aiding in early disease detection and provides potentially critical information for conservation of the endangered California condor as it continues to expand its range and encounter new infectious disease threats.
  • Chilled frogs are hot: hibernation and reproduction of the Endangered mountain yellow-legged frog Rana muscosa

    Santana, Frank E.; Swaisgood, Ronald R.; Lemm, Jeffrey M.; Fisher, Robert N.; Clark, Rulon W. (2015)
    In the face of the sixth great extinction crisis, it is imperative to establish effective breeding protocols for amphibian conservation breeding programs. Captive efforts should not proceed by trial and error, nor should they jump prematurely to assisted reproduction techniques, which can be invasive, difficult, costly, and, at times, counterproductive. Instead, conservation practitioners should first look to nature for guidance, and replicate key conditions found in nature in the captive environment, according to the ecological and behavioral requirements of the species. We tested the effect of a natural hibernation regime on reproductive behaviors and body condition in the Endangered mountain yellow-legged frog Rana muscosa. Hibernation had a clear positive effect on reproductive behavior, manifesting in vocal advertisement signaling, female receptivity, amplexus, and oviposition. These behaviors are critical components of courtship that lead to successful reproduction. Our main finding was that captive R. muscosa require a hibernation period for successful reproduction, as only hibernated females produced eggs and only hibernated males successfully fertilized eggs. Although hibernation also resulted in a reduced body condition, the reduction appeared to be minimal with no associated mortality. The importance of hibernation for reproduction is not surprising, since it is a major component of the conditions that R. muscosa experiences in the wild. Other amphibian conservation breeding programs can also benefit from a scientific approach that tests the effect of natural ecological conditions on reproduction. This will ensure that captive colonies maximize their role in providing genetic reservoirs for assurance and reintroduction efforts.
  • Chimpanzee population structure in Cameroon and Nigeria is associated with habitat variation that may be lost under climate change

    Sesink Clee, Paul R.; Abwe, Ekwoge E.; Ambahe, Ruffin D.; Anthony, Nicola M.; Fotso, Roger; Locatelli, Sabrina; Maisels, Fiona; Mitchell, Matthew W.; Morgan, Bethan J.; Pokempner, Amy A.; et al. (2015)
    Background: The Nigeria-Cameroon chimpanzee (Pan troglodytes ellioti) is found in the Gulf of Guinea biodiversity hotspot located in western equatorial Africa. This subspecies is threatened by habitat fragmentation due to logging and agricultural development, hunting for the bushmeat trade, and possibly climate change. Although P. t. ellioti appears to be geographically separated from the neighboring central chimpanzee (P. t. troglodytes) by the Sanaga River, recent population genetics studies of chimpanzees from across this region suggest that additional factors may also be important in their separation. The main aims of this study were: 1) to model the distribution of suitable habitat for P. t. ellioti across Cameroon and Nigeria, and P. t. troglodytes in southern Cameroon, 2) to determine which environmental factors best predict their optimal habitats, and 3) to compare modeled niches and test for their levels of divergence from one another. A final aim of this study was to examine the ways that climate change might impact suitable chimpanzee habitat across the region under various scenarios. Results: Ecological niche models (ENMs) were created using the software package Maxent for the three populations of chimpanzees that have been inferred to exist in Cameroon and eastern Nigeria: (i) P. t. troglodytes in southern Cameroon, (ii) P. t. ellioti in northwestern Cameroon, and (iii) P. t. ellioti in central Cameroon. ENMs for each population were compared using the niche comparison test in ENMtools, which revealed complete niche divergence with very little geographic overlap of suitable habitat between populations. Conclusions: These findings suggest that a positive relationship may exist between environmental variation and the partitioning of genetic variation found in chimpanzees across this region. ENMs for each population were also projected under three different climate change scenarios for years 2020, 2050, and 2080. Suitable habitat of P. t. ellioti in northwest Cameroon / eastern Nigeria is expected to remain largely unchanged through 2080 in all considered scenarios. In contrast, P. t. ellioti in central Cameroon, which represents half of the population of this subspecies, is expected to experience drastic reductions in its ecotone habitat over the coming century.
  • An autonomous GPS geofence alert system to curtail avian fatalities at wind farms

    Sheppard, James; McGann, Andrew; Lanzone, Michael; Swaisgood, Ronald R. (2015)
    Wind energy developments are increasingly proliferating as nations seek to secure clean and renewable energy supplies. Wind farms have serious impacts on avifauna populations through injuries sustained by collisions with turbines. Our aim was to develop new biotelemetric technologies to minimize collision risks, particularly for threatened and endangered bird species whose ranges overlap with current and future wind farm sites.
  • Detailed monitoring of a small but recovering population reveals sublethal effects of disease and unexpected interactions with supplemental feeding

    Tollington, S.; Greenwood, A.; Jones, C.G.; Hoeck, Paquita; Chowrimootoo, A.; Smith, D.; Richards, H.; Tatayah, V.; Groombridge, J.J. (2015)
    Infectious diseases are widely recognized to have substantial impact on wildlife populations. These impacts are sometimes exacerbated in small endangered populations, and therefore, the success of conservation reintroductions to aid the recovery of such species can be seriously threatened by outbreaks of infectious disease. Intensive management strategies associated with conservation reintroductions can further compound these negative effects in such populations. Exploring the sublethal effects of disease outbreaks among natural populations is challenging and requires longitudinal, individual life‐history data on patterns of reproductive success and other indicators of individual fitness. Long‐term monitoring data concerning detailed reproductive information of the reintroduced Mauritius parakeet (Psittacula echo ) population collected before, during and after a disease outbreak was investigated. Deleterious effects of an outbreak of beak and feather disease virus (BFDV ) were revealed on hatch success, but these effects were remarkably short‐lived and disproportionately associated with breeding pairs which took supplemental food. Individual BFDV infection status was not predicted by any genetic, environmental or conservation management factors and was not associated with any of our measures of immune function, perhaps suggesting immunological impairment. Experimental immunostimulation using the PHA (phytohaemagglutinin assay) challenge technique did, however, provoke a significant cellular immune response. We illustrate the resilience of this bottlenecked and once critically endangered, island‐endemic species to an epidemic outbreak of BFDV and highlight the value of systematic monitoring in revealing inconspicuous but nonetheless substantial ecological interactions. Our study demonstrates that the emergence of such an infectious disease in a population ordinarily associated with increased susceptibility does not necessarily lead to deleterious impacts on population growth and that negative effects on reproductive fitness can be short‐lived.
  • Photos provide information on age, but not kinship, of Andean bear

    Van Horn, Russell C.; Zug, Becky; Appleton, Robyn D.; Velez-Liendo, Ximena; Paisley, Susanna; LaCombe, Corrin (2015)
    Using photos of captive Andean bears of known age and pedigree, and photos of wild Andean bear cubs <6 months old, we evaluated the degree to which visual information may be used to estimate bears’ ages and assess their kinship. We demonstrate that the ages of Andean bear cubs ≤6 months old may be estimated from their size relative to their mothers with an average error of <0.01 ± 13.2 days (SD; n = 14), and that ages of adults ≥10 years old may be estimated from the proportion of their nose that is pink with an average error of <0.01 ± 3.5 years (n = 41). We also show that similarity among the bears’ natural markings, as perceived by humans, is not associated with pedigree kinship among the bears (R2 < 0.001, N = 1,043, p = 0.499). Thus, researchers may use photos of wild Andean bears to estimate the ages of young cubs and older adults, but not to infer their kinship. Given that camera trap photos are one of the most readily available sources of information on large cryptic mammals, we suggest that similar methods be tested for use in other poorly understood species.
  • A road map for 21st century genetic restoration: Gene pool enrichment of the black-footed ferret

    Wisely, S. M.; Ryder, Oliver A.; Santymire, R. M.; Engelhardt, J. F.; Novak, B. J. (2015)
    Interspecies somatic cell nuclear transfer (iSCNT) could benefit recovery programs of critically endangered species but must be weighed with the risks of failure. To weigh the risks and benefits, a decision-making process that evaluates progress is needed. Experiments that evaluate the efficiency and efficacy of blastocyst, fetal, and post-parturition development are necessary to determine the success or failure or species-specific iSCNT programs. Here, we use the black-footed ferret (Mustela nigripes) as a case study for evaluating this emerging biomedical technology as a tool for genetic restoration. The black-footed ferret has depleted genetic variation yet genome resource banks contain genetic material of individuals not currently represented in the extant lineage. Thus, genetic restoration of the species is in theory possible and could help reduce the persistent erosion of genetic diversity from drift. Extensive genetic, genomic, and reproductive science tools have previously been developed in black-footed ferrets and would aid in the process of developing an iSCNT protocol for this species. Nonetheless, developing reproductive cloning will require years of experiments and a coordinated effort among recovery partners. The information gained from a well-planned research effort with the goal of genetic restoration via reproductive cloning could establish a 21st century model for evaluating and implementing conservation breeding that would be applicable to other genetically impoverished species.

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