No evidence for precipitous declines of harlequin frogs (Atelopus) in the Guyanas

The species-rich Neotropical harlequin frogs (Atelopus) have experienced drastic population reductions that some herald as potential extinction at the genus level. Principal causes for this included an emerging infectious disease, chytridiomycosis, caused by the chytrid fungus, and climate change. Responses by Atelopus species typically involve rapid population crashes''. We here report on two populations of Atelopus hoogmoedi from Suriname and Guyana which show densities similar to other members in the genus before population crashes''. Further, tests for the chytrid fungus proved negative, suggesting that it may currently be absent at these two locations. Our findings indicate that A. hoogmoedi may currently be escaping extinction processes plaguing the genus elsewhere. Nevertheless, this may change rapidly, as has been shown in other Atelopus. For this reason, we strongly encourage proactive conservation measures before the pattern observed in so many congenerics is played out again.