Ecology: Amphibian chytrid fungus discovered in Madagascar

Madagascar’s diverse amphibian populations may be threatened by the infectious disease-causing chytrid fungus, a study in Scientific Reports suggests. Batrachochytrium dendrobatidis (Bd), which has not previously been reported in Madagascar, appears to have arrived recently. However, researchers cannot rule out the possibility that a native family of Bd has always been present but has previously remained undetected.

Chytridiomycosis, an emerging infectious disease caused by Bd, has been linked to population declines or even extinctions of amphibian species. The amphibian chytrid fungus has been detected on almost every continent, although there are some regions that are considered disease-free, including Papua New Guinea and Madagascar. However, Bd surveys carried out in Madagascar from 2005 to 2014 reveal the detection of Bd in wild amphibians in 2010, Molly Bletz, Goncalo Rosa, Franco Andreone and colleagues report. The fungus has been recorded in five different areas of the country between 2010 and 2014, but it is unclear whether Bd has been introduced to the island recently or if it is endemic.

Evidence for negative effects associated with Bd presence in Madagascar is so far lacking: amphibians carrying the fungus have not displayed any signs of chytridiomycosis and no Bd-associated deaths have been reported. Nevertheless, the authors recommend continued monitoring of Bd presence in Madagascar to enable an effective response should the fungus become a threat to the local amphibian populations.