Abstract

We comment on the results of a previous study which evaluate the accuracy of mouthpart depigmentation as an indicator of Batrachochytrium dendrobatidis (Bd) infection in anuran larvae. Macroscopic mouthpart inspection is a useful technique for Bd identification since it is practical and nonlethal; however, this method is also expected to result in increased rates of false negatives and false positives when compared to other methods. We therefore suggest that there are scenarios in which the use of mouthpart depigmentation is not appropriate, and we present a conceptual framework for deciding when mouthpart depigmentation is an appropriate indicator of oral chytridiomycosis in tadpoles. We conclude that more sensitive techniques are preferable when false positives or false negatives could result in the incorrect classification of populations as infected or uninfected, namely when Bd is absent or present at low prevalence. In contrast, mouthpart depigmentation is an appropriate indicator of infection when Bd prevalence is high and especially when conservation or practical concerns preclude lethal methods such as histological preparation.