Interventions for Reducing Extinction Risk in Chytridiomycosis-Threatened Amphibians

Authors

  • BEN C. SCHEELE,

    1. ARC Centre of Excellence for Environmental Decisions, National Environmental Research Program Environmental Decisions Hub, Fenner School of Environment and Society, Forestry Building [48], Australian National University, Canberra, Australia
    2. NSW Office of Environment and Heritage, Queanbeyan, Australia
    Search for more papers by this author
  • DAVID A. HUNTER,

    1. NSW Office of Environment and Heritage, Queanbeyan, Australia
    Search for more papers by this author
  • LAURA F. GROGAN,

    1. One Health Research Group, School of Public Health, Tropical Medicine and Rehabilitation Sciences, James Cook University, Townsville, Australia
    Search for more papers by this author
  • LEE BERGER,

    1. One Health Research Group, School of Public Health, Tropical Medicine and Rehabilitation Sciences, James Cook University, Townsville, Australia
    Search for more papers by this author
  • JON E. KOLBY,

    1. One Health Research Group, School of Public Health, Tropical Medicine and Rehabilitation Sciences, James Cook University, Townsville, Australia
    2. IUCN SSC Amphibian Specialist Group, Regional Co-Chair (Honduras)
    Search for more papers by this author
  • MICHAEL S. MCFADDEN,

    1. Taronga Conservation Society Australia, Mosman, Australia
    Search for more papers by this author
  • GERRY MARANTELLI,

    1. Amphibian Research Centre, Merlynston, Australia
    Search for more papers by this author
  • LEE F. SKERRATT,

    1. One Health Research Group, School of Public Health, Tropical Medicine and Rehabilitation Sciences, James Cook University, Townsville, Australia
    Search for more papers by this author
  • DON A. DRISCOLL

    1. ARC Centre of Excellence for Environmental Decisions, National Environmental Research Program Environmental Decisions Hub, Fenner School of Environment and Society, Forestry Building [48], Australian National University, Canberra, Australia
    Search for more papers by this author

Abstract

Wildlife diseases pose an increasing threat to biodiversity and are a major management challenge. A striking example of this threat is the emergence of chytridiomycosis. Despite diagnosis of chytridiomycosis as an important driver of global amphibian declines 15 years ago, researchers have yet to devise effective large-scale management responses other than biosecurity measures to mitigate disease spread and the establishment of disease-free captive assurance colonies prior to or during disease outbreaks. We examined the development of management actions that can be implemented after an epidemic in surviving populations. We developed a conceptual framework with clear interventions to guide experimental management and applied research so that further extinctions of amphibian species threatened by chytridiomycosis might be prevented. Within our framework, there are 2 management approaches: reducing Batrachochytrium dendrobatidis (the fungus that causes chytridiomycosis) in the environment or on amphibians and increasing the capacity of populations to persist despite increased mortality from disease. The latter approach emphasizes that mitigation does not necessarily need to focus on reducing disease-associated mortality. We propose promising management actions that can be implemented and tested based on current knowledge and that include habitat manipulation, antifungal treatments, animal translocation, bioaugmentation, head starting, and selection for resistance. Case studies where these strategies are being implemented will demonstrate their potential to save critically endangered species.

Intervenciones para Reducir el Riesgo de Extinción en Anfibios Amenazados por la Quitridiomicosis

Resumen

Las enfermedades en la vida silvestre presentan una creciente amenaza para la biodiversidad y son un gran desafío para el manejo. Un ejemplo notable de esto es el surgimiento de la quitridiomicosis. A pesar del diagnóstico de la quitridiomicosis como un conductor importante de la declinación global de anfibios en los últimos 15 años, los investigadores todavía no han podido concebir respuestas de manejo efectivas a gran escala, más allá de las medidas de bioseguridad para mitigar el esparcimiento de la enfermedad y el establecimiento de colonias seguras y libres de enfermedad antes o durante el brote de la enfermedad. Examinamos el desarrollo de acciones de manejo que pueden implementarse en poblaciones sobrevivientes después de una epidemia. Desarrollamos un marco de trabajo conceptual con intervenciones claras para guiar al manejo experimental y a la investigación aplicada para que puedan prevenirse futuras extinciones de anfibios amenazados por quitridiomicosis. Dentro de nuestro marco de trabajo hay dos estrategias de manejo: reducir Batrachochytrium dendrobatidis (el hongo que causa la quitridiomicosis) en el ambiente o en los anfibios e incrementar la capacidad de persistencia de las poblaciones a pesar del aumento en la mortalidad por la enfermedad. La última estrategia enfatiza que la mitigación no necesariamente necesita enfocarse en reducir la mortalidad asociada con la enfermedad. Proponemos acciones de manejo prometedoras que puedan implementarse y probarse con base en el conocimiento actual y que incluyan manipulación de hábitat, tratamientos antimicóticos, traslocación de animales, bioaumento, iniciar con ventajas y selección para la resistencia. Los estudios de caso en los que se están implementando estas estrategias demostrarán su potencial para rescatar especies en peligro crítico.

Ancillary