Fighting the impact of chytridiomycosis 

Despite the rise of disease as a key conservation challenge, the management of wildlife diseases affecting biodiversity, especially non-mammals, remains in its infancy. Chytridiomycosis, for example, caused by the pathogenic skin fungus Batrachochytrium dendrobatidis, has devastated amphibian communities globally and is considered the worst recorded wildlife disease. Infection has been detected in 42% of amphibian species sampled, and a conservative estimate suggests that chytridiomycosis has caused the severe decline or extinction of over 200 species. Despite the diagnosis of chytridiomycosis as an important driver of global amphibian declines 15 years ago, researchers have yet to devise effective large-scale responses (other than biosecurity measures) to mitigate the spread of the disease. Nor have they been able to establish captive assurance colonies that are disease-free prior to or during disease outbreaks.

Ben Scheele and colleagues examined the development of management actions that can be implemented after an epidemic in surviving populations. They developed a conceptual framework with clear interventions to guide experimental management so that further extinctions of amphibian species threatened by chytridiomycosis might be prevented.

Within their framework there are two management approaches: reducing Batrachochytrium dendrobatidis 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. They 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 of amphibians.


Reference 

Scheele BC, DA Hunter, LF Grogan, L Berger, JE Kolby, MS Mcfadden, G Marantelli, LF Skerratt and DA Driscoll (2014). Interventions for Reducing Extinction Risk in Chytridiomycosis-Threatened Amphibians. Conservation Biology 28(5):1195-1205. http://onlinelibrary.wiley.com/doi/10.1111/cobi.12322/abstract

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