Spread of Chytridiomycosis Has Caused the Rapid Global Decline and Extinction of Frogs

Abstract

The global emergence and spread of the pathogenic, virulent, and highly transmissible fungus Batrachochytrium dendrobatidis, resulting in the disease chytridiomycosis, has caused the decline or extinction of up to about 200 species of frogs. Key postulates for this theory have been completely or partially fulfilled. In the absence of supportive evidence for alternative theories despite decades of research, it is important for the scientific community and conservation agencies to recognize and manage the threat of chytridiomycosis to remaining species of frogs, especially those that are naive to the pathogen. The impact of chytridiomycosis on frogs is the most spectacular loss of vertebrate biodiversity due to disease in recorded history.

Integrating species traits with extrinsic threats: closing the gap between predicting and preventing species declines

“…We review our findings with reference to the specifics of our study system, highlighting where our approach offers insight that is broadly relevant to endangered species and protected area management, including IUCN Red List assessments and the treatment of data-deficient species. The effects of Bd on amphibians are inherently nonrandom with respect to the species affected [13,42], and the role of Bd in many of the 32 declining stream or moist bog/soak species in the high-Bd group (node 4) in this study has been reasonably well documented (e.g. Pseudophryne corroborree, Taudactylus acutirostris, Taudactylus eungellensis, Litoria (Nyctimistes) dayi, Litoria genimaculata, Litoria leseuerii, Litoria pearsoniana, Litoria rheocola; [13,18,43]).…”

“…A third category grouped species declining owing to 'enigmatic' (unknown) causes [10]. With the discovery of chytridiomycosis [18,19], many of these enigmatic declines have been attributed to the effects of this pandemic disease [13]. Nevertheless, in contrast to the progress that has been made in addressing habitat degradation in recent quantitative studies of extinction risk in amphibians (e.g.…”

Host persistence or extinction from emerging infectious disease: insights from white-nose syndrome in endemic and invading regions

“…It remains to be seen if the speed of evolution will be rapid enough to prevent extinctions of the most heavily impacted species [2,6,8,38,41,42]. Management actions to conserve these species face the challenge of reducing disease impacts to prevent extinction without compromising species' evolutionary response to this and other diseases.…”

Fitness Consequences of Infection by Batrachochytrium dendrobatidis in Northern Leopard Frogs (Lithobates pipiens)

“…Chytridiomycosis is a recently discovered, globally important, emerging amphibian disease that is caused by the fungal pathogen Batrachochytrium dendrobatidis (Bd). In some parts of the world this pathogen has caused mass die-offs and even extinctions (Lips et al 2005;Skerratt et al 2007), whereas in others amphibians are heavily infected but show no acute signs of disease (Rothermel et al 2008;Kinney et al 2011). Amphibians in eastern North America fall into the latter category, where infection prevalence may be high (Longcore et al 2007;Rothermel et al 2008;Gaertner et al 2009;Kinney et al 2011;Chatfield et al 2012) yet mass die-offs attributable to chytridiomycosis have not been observed.…”