Widespread amphibian declines from epidemic disease driven by global warming

Golden Toad Laboratory for Conservation, Monteverde Cloud Forest Preserve and Tropical Science Center, Santa Elena, Puntarenas 5655-73, Costa Rica.
Nature (Impact Factor: 41.46). 01/2006; 439(7073):161-7. DOI: 10.1038/nature04246
Source: PubMed


As the Earth warms, many species are likely to disappear, often because of changing disease dynamics. Here we show that a recent mass extinction associated with pathogen outbreaks is tied to global warming. Seventeen years ago, in the mountains of Costa Rica, the Monteverde harlequin frog (Atelopus sp.) vanished along with the golden toad (Bufo periglenes). An estimated 67% of the 110 or so species of Atelopus, which are endemic to the American tropics, have met the same fate, and a pathogenic chytrid fungus (Batrachochytrium dendrobatidis) is implicated. Analysing the timing of losses in relation to changes in sea surface and air temperatures, we conclude with 'very high confidence' (> 99%, following the Intergovernmental Panel on Climate Change, IPCC) that large-scale warming is a key factor in the disappearances. We propose that temperatures at many highland localities are shifting towards the growth optimum of Batrachochytrium, thus encouraging outbreaks. With climate change promoting infectious disease and eroding biodiversity, the urgency of reducing greenhouse-gas concentrations is now undeniable.

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    • "These interactions between environmental and genetic control are evident in the many field surveys of pathogen prevalence in wild populations (Burdon, 1977; Vercelli, 2004; Hunter, 2005). For example, models predict that Bd has a higher probability of occurrence at high elevations, where mean temperatures and cloud cover provide better (or ideal) conditions for its growth (Piotrowski et al., 2004; Pounds et al., 2006). However, not all high elevation sites appear to respond equally to Bd infection (Lips, 1998; La Marca et al., 2005; Brem and Lips, 2008; Kriger and Hero, 2008; Gründler et al., 2012). "
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    • "Rapid changes in atmospheric conditions, habitat fragmentation, pollution, invasive species and pathogens, individually and collectively, represent a greater threat to existence than most living species have previously experienced (Barnosky et al., 2011). Amphibians are much affected by the current biodiversity crisis, with well-documented recent extinctions in response to such stressors (Pounds et al., 2006). At least 32% of existing amphibians are at threat from extinction (Stuart et al., 2004) and numerous populations are facing major population declines, morphological deformities and severe pathogen infections (Daszak et al., 2003). "
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