Article

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

ABSTRACT

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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    • "We found that stream-breeding species with small clutches are especially sensitive to habitat alteration, which has not been previously reported.Cooper et al. (2008)found that clutch size is a significant component of geographical range size, whileHero et al. (2005)suggested that more fecund species might have greater potential to spread to new areas and occupy large geographical ranges. If larger clutches are related to larger ranges, higher dispersal ability and colonization success in amphibians, smaller clutches may render species more susceptible to stochastic events and anthropogenic activities, resulting in increased sensitivity to habitat alteration (Grafe et al., 2004;Pounds et al., 2006). Range size was a predictor of species vulnerability to habitat alteration , especially for pond breeders. "
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    • "Amphibians are regarded as the most endangered class of vertebrates (Gibbons et al. 2000, Stuart et al. 2004), and their global decline is matter of great concern because of its consequences for species conservation and ecosystem function (Hocking & Babbitt 2014, Cortez-Gomes et al. 2015). The drivers of amphibian population declines are various and wellknown: habitat destruction, alteration and fragmentation; pollution; use of pesticides and fertilizers; direct capture; climate change; diseases; and the introduction of allochthonous species (Webb & Joss 1997, Kats & Ferrer 2003, Pounds et al. 2006, Cushman 2006, Mann et al. 2009). Due to their vulnerability, the European Union has included many native amphibian species in the Habitat Directive 92/43/EEC, in order to guarantee their protection by the establishment of protected areas: Sites of Community Importance (SCIs). "
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