Chytridiomycosis surveillance in the critically endangered Montseny brook newt, Calotriton arnoldi, northeastern Spain

Chytridiomycosis, a disease caused by the pathogenic fungus Batrachochytrium dendrobatidis (Bd) has caused significant declines of amphibian populations in different areas of Spain. The critically endangered Montseny brook newt (Calotriton arnoldi) is endemic to the mountain region of Montseny in Catalonia, northeast Spain. As part of its conservation plan, special attention was needed to evaluate the population health status, which remained uncertain. From 2007 to 2011, we conducted a survey in Montseny Natural Park and examined 158 Montseny brook newts, 14 fire salamanders and 2 common toads for the presence of Bd using quantitative real-time Taqman PCR (qPCR) assay. All samples were negative to this pathogen suggesting that Bd is absent in the region or present in such a low level that it was undetected. The implementation of disease surveillance in wildlife, especially in endangered species, is of crucial importance for the detection of subclinical infection and prompt adoption of counter measures.