• Cache pilfering in a granivore guild: Implications for reintroduction management

      Chock, Rachel Y.; Grether, Gregory F.; Shier, Debra M. (2019)
      Reintroduction programs that release endangered species back into areas from which they have been extirpated rarely take competitive interactions between species into account....
    • California Condor North American Studbook (Gymnogyps californianus)

      Mace, Michael E. (Diego Zoo GlobalEscondido, CA, 2014)
    • California condor North American studbook (Gymnogyps californianus)

      Mace, Michael E.; (Zoological Society of San DiegoEscondido, CA, 2010)
    • California condor recovery: a work in progress

      Wallace, Michael P.; Lamont, Miles M. (Hancock House PublishersToronto, Ontario, Canada. Surrey, BC, Canada., 2014)
    • California condor studbook

      Mace, Michael E. (San Diego Zoo GlobalSan Diego: San, 2012)
    • California Condor Studbook

      Mace, Michael E. (Zoological Society of San DiegoSan Diego, 2011)
    • California condors and DDT: Examining the effects of endocrine disrupting chemicals in a critically endangered species

      Tubbs, Christopher W. (2016)
      In 1987, the last free-flying California condor (Gymnogyps californianus) was captured and brought into captivity, rendering the species extinct in the wild. At the time, only 27 condors remained. Today, the population numbers approximately 430 individuals and though condors continue their remarkable recovery, they still face numerous challenges. One challenge, specific to condors inhabiting coastal regions, is exposure to the endocrine disrupting chemical (EDC) p,p'-DDE, through the scavenging of marine mammal carcasses. The exposure levels these birds currently experience appears to be causing eggshell thinning, reminiscent of the phenomenon that nearly collapsed populations of several avian species decades ago. We were interested in further exploring the potential effects of EDCs on California condors. Investigating EDC effects on a critically endangered species like the condor can be difficult, with limited options for studies that can be feasibly conducted. Therefore, we conducted non-invasive, in vitro estrogen receptor (ESR) activation assays to characterize activation by EDCs that coastal condors encounter. Here, I give a brief history of EDCs effects on birds, and in particular the California condor. Additionally, our ESR data are summarized and mechanisms of eggshell thinning are reviewed, highlighting the potential implications of EDC exposure on the continued recovery of the California condor.
    • Camera settings and biome influence the accuracy of citizen science approaches to camera trap image classification

      Egna, Nicole; O'Connor, David; Stacy-Dawes, Jenna; Tobler, Mathias W.; Pilfold, Nicholas W.; Neilson, Kristin; Simmons, Brooke; Davis, Elizabeth Oneita; Bowler, Mark; Fennessy, Julian; et al. (2020)
      Scientists are increasingly using volunteer efforts of citizen scientists to classify images captured by motion-activated trail cameras. The rising popularity of citizen science reflects its potential to engage the public in conservation science and accelerate processing of the large volume of images generated by trail cameras. While image classification accuracy by citizen scientists can vary across species, the influence of other factors on accuracy is poorly understood. Inaccuracy diminishes the value of citizen science derived data and prompts the need for specific best-practice protocols to decrease error. We compare the accuracy between three programs that use crowdsourced citizen scientists to process images online: Snapshot Serengeti, Wildwatch Kenya, and AmazonCam Tambopata. We hypothesized that habitat type and camera settings would influence accuracy. To evaluate these factors, each photograph was circulated to multiple volunteers. All volunteer classifications were aggregated to a single best answer for each photograph using a plurality algorithm. Subsequently, a subset of these images underwent expert review and were compared to the citizen scientist results. Classification errors were categorized by the nature of the error (e.g., false species or false empty), and reason for the false classification (e.g., misidentification). Our results show that Snapshot Serengeti had the highest accuracy (97.9%), followed by AmazonCam Tambopata (93.5%), then Wildwatch Kenya (83.4%). Error type was influenced by habitat, with false empty images more prevalent in open-grassy habitat (27%) compared to woodlands (10%). For medium to large animal surveys across all habitat types, our results suggest that to significantly improve accuracy in crowdsourced projects, researchers should use a trail camera set up protocol with a burst of three consecutive photographs, a short field of view, and determine camera sensitivity settings based on in situ testing. Accuracy level comparisons such as this study can improve reliability of future citizen science projects, and subsequently encourage the increased use of such data.
    • Can science save the giant panda (Ailuropoda melanoleuca)? Unifying science and policy in an adaptive management paradigm

      Swaisgood, Ronald R.; Wei, Fuwen; Mcshea, William J.; Wildt, David E.; Kouba, Andrew J.; Zhang, Zejun (2011)
      …Here, we review recent developments in giant panda conservation science and propose a strategic plan for moving panda conservation forward…. Specific threats, such as habitat destruction, anthropogenic disturbance and fragmented nonviable populations, need to be addressed simultaneously by researchers, managers and policy-makers working in concert to understand and overcome these obstacles to species recovery. With the backing of the Chinese Government and the conservation community, the giant panda can become a high-profile test species for this much touted, but rarely implemented, approach to conservation management….
    • Captive breeding and re-introductions of the Monuriki Island Crested Iguana in Fiji

      Chand, R; Niukula, J; Vadada, J; Fisher, R; Lovich, Kim; Pasachnik, Stesha A.; Rasalato, S; Thaman, B; Seniloli, E; Tuamoto, T; et al. (IUCN/SSC Re-introduction Specialist Group and Abu Dhabi, UAE: Environment Agency-Abu DhabiGland, Gland, Switzerland, 2016)
      The Fijian crested iguana (Brachylophus vitiensis) is an arboreal, herbivorous lizard found on only a small number of islands with native dry or littoral forest in western Fiji. Its population is secure only on the sanctuary island of Yadua Taba, where >12,000 individuals exist; this equates to over 200 individuals/ha in the best forest habitat. All other island populations appear to be low and declining (mostly <100 individuals), and survive on communally owned land which is mostly outside the control of central government legislation (Harlow et al., 2007)....
    • Capturing pests and releasing ecosystem engineers: translocation of common but diminished species to re-establish ecological roles

      Swaisgood, Ronald R.; Montagne, J.P.; Lenihan, C. M.; Wisinski, Colleen L.; Nordstrom, Lisa A.; Shier, Debra M. (2019)
      Translocation of abundant but declining ecologically important species for re-establishing more sustainable ecosystem function is a neglected but promising form of conservation intervention. Here, we developed a translocation program in which we capture pests and release ecosystem engineers, by relocating California ground squirrels Otospermophilus beecheyi from areas where they are unwanted to conserved lands where they can perform ecosystem services such as burrowing and vegetation alteration. We accomplished this using an experimental approach in which some factors were measured or experimentally manipulated, while others were held constant. We translocated 707 squirrels and examined survival and movement patterns as a function of several translocation tactics and ecological factors. We released squirrels at 9 different plots with varying ecological contexts and at each plot experimentally manipulated post-release habitat using mowing, mowing plus the use of augers to establish starter burrows, and controls that remained unmanipulated. The most influential variables affecting short-term survival, dispersal, and long-term persistence were factors relating to soils and vegetation structure. Translocated squirrels had higher initial survival on plots where dense exotic grasses were experimentally altered, greater dispersal when released at sites with less friable clay soils, and improved long-term persistence at sites characterized by more friable soils associated with metavolcanic than alluvial geological layers. Squirrel persistence was also improved when translocations supplemented previous translocation sites than during initial translocations to sites containing no resident squirrels. Our results demonstrate how California ground squirrels can be successfully translocated as part of a larger objective to favorably alter ecological function in novel grassland ecosystems dominated by non-native vegetation. In broader context, our study highlights the importance of testing release strategies, and examining habitat variables and restoration techniques more closely when selecting release sites to improve translocation outcomes.
    • Case series: clinical salmonellosis in four black rhinoceros (diceros bicornis) calves

      Love, David; Madrigal, Rodolfo; Cerveny, Shannon; Raines, Janis; Rideout, Bruce; Lung, Nancy P. (2017)
      Although Salmonella spp. infection has been identified in captive and free-ranging rhinoceros, clinical cases in black rhinoceros (Diceros bicornis) calves have not been described. This case series describes clinical salmonellosis in four black rhinoceros calves....
    • Cathemeral

      Eppley, Timothy M.; Donati, Giuseppe; Vonk, Jennifer; Shackelford, Todd (Springer NatureNew York, 2019)
      Within this encyclopedia article, we provide an overview of the term “Cathemeral”. This is applied to the pattern of an organism’s activity that occurs during both the light and dark portions of the 24-h cycle....
    • Causes of mortality in anuran amphibians from an ex-situ survival assurance colony in Panama

      Pessier, Allan P.; Baitchman, E.J.; Crump, P.; Wilson, B.; Griffith, E.; Ross, H. (2014)
      …This study reviewed postmortem findings in 167 frogs from 13 species that died in a large Panamanian rescue and survival assurance population between 2006 and 2011…. Applied research efforts to improve sustainability of survival assurance populations should focus on elucidating optimal husbandry practices for diverse species, improving methods for nutritional supplementation of cultured insects and examination of the role of water composition in disease development.
    • Center for Plant Conservation's Best Practice Guidelines for the reintroduction of rare plants

      Maschinski, Joyce; Albrecht, Matthew A. (2017)
      Recent estimates indicate that one-fifth of botanical species worldwide are considered at risk of becoming extinct in the wild. One available strategy for conserving many rare plant species is reintroduction, which holds much promise especially when carefully planned by following guidelines and when monitored long-term. We review the Center for Plant Conservation Best Reintroduction Practice Guidelines and highlight important components for planning plant reintroductions. Before attempting reintroductions practitioners should justify them, should consider alternative conservation strategies, understand threats, and ensure that these threats are absent from any recipient site. Planning a reintroduction requires considering legal and logistic parameters as well as target species and recipient site attributes. Carefully selecting the genetic composition of founders, founder population size, and recipient site will influence establishment and population growth. Whenever possible practitioners should conduct reintroductions as experiments and publish results. To document whether populations are sustainable will require long-term monitoring for decades, therefore planning an appropriate monitoring technique for the taxon must consider current and future needs. Botanical gardens can play a leading role in developing the science and practice of plant reintroduction.
    • Cerebral Angiostrongylus cantonensis infection in a captive African pygmy falcon (Polihierax semitorquatus) in southern California

      Burns, Rachel E.; Bicknese, Elizabeth; Qvarnstrom, Yvonne; DeLeon-Carnes, Marlene; Drew, Clifton P.; Gardiner, Chris H.; Rideout, Bruce (2014)
      A 10-month-old, female African pygmy falcon (Polihierax semitorquatus) hatched and housed at the San Diego Zoo developed neurologic signs and died from a cerebral infection with the rat lungworm Angiostrongylus cantonensis…. To the authors’ knowledge, this infection has not previously been reported in a bird in the United States and has not been known to be naturally acquired in any species in this region of the world. The source of the infection was not definitively determined but was possibly feeder geckos (Hemidactylus frenatus) imported from Southeast Asia where the parasite is endemic.
    • Challenges in the development of semen cryopreservation protocols for snakes

      Young, Carly; Ravida, Nicole; Durrant, Barbara S. (2019)
    • Challenges of learning to escape evolutionary traps

      Greggor, Alison L.; Trimmer, Pete C.; Barrett, Brendan J.; Sih, Andrew (2019)
      Many animals respond well behaviorally to stimuli associated with human-induced rapid environmental change (HIREC), such as novel predators or food sources. Yet others make errors and succumb to evolutionary traps: approaching or even preferring low quality, dangerous or toxic options, avoiding beneficial stimuli, or wasting resources responding to stimuli with neutral payoffs. A common expectation is that learning should help animals adjust to HIREC; however, learning is not always expected or even favored in many scenarios that expose animals to ecological and evolutionary traps. We propose a conceptual framework that aims to explain variation in when learning can help animals avoid and escape traps caused by HIREC. We first clarify why learning to correct two main types of errors (avoiding beneficial options, and not avoiding detrimental options) might be difficult (limited by constraints). We then identify and discuss several key behavioral mechanisms (adaptive sampling, generalization, habituation, reversal learning) that can be targeted to help animals learn to avoid traps. Finally, we discuss how individual differences in neophobia/neophilia and personality relate to learning in the context of HIREC traps, and offer some general guidance for disarming traps. Given how devastating traps can be for animal populations, any breakthrough in mitigating trap outcomes via learning could make the difference in developing effective solutions.
    • Change: Risks and predictability

      Hobohm, Carsten; Vanderplank, Sula E.; Hobohm, Carsten; Cabin, Robert J. (Springer International PublishingCham, Switzerland, 2021)
      ...This study deals with the question of how stochastic effects, changing ecological conditions, the introduction of alien species, and dramatic events in general, can be characterized and quantified. We propose some initial ideas for the establishment of an indicator system for constancy and change through time, with respect to the effect size....
    • Changes in vocal repertoire of the Hawaiian crow, Corvus hawaiiensis, from past wild to current captive populations

      Tanimoto, Ann M.; Hart, Patrick J.; Pack, Adam A.; Switzer, Richard A.; Banko, Paul C.; Ball, Donna L.; Sebastián-González, Esther; Komarczyk, Lisa; Warrington, Miyako H. (2017)
      ...We compared the vocal repertoire of three of the last four wild 'alalā pairs from the early 1990s to three current captive pairs on the Island of Hawai'i to determine how acoustic behaviour has been affected by changes in their social and physical environment. Over 18 h of recordings from wild breeding pairs were analysed and compared with 44 h from captive breeding pairs....