Low Prevalence of Batrachochytrium dendrobatidis Among 14 Amphibian Species at a Protected Site in the Northeastern United States

Amphibian declines are occurring rapidly and are driven by multiple factors, including emerging infectious agents, such as Batrachochytrium dendrobatidis (Bd). While Bd is globally distributed, it is also known to affect amphibians in Pennsylvania. Here, we screened 198 individuals of 14 amphibian species (5 anurans and 9 caudates) using traditional PCR methods at Powdermill Nature Reserve in western Pennsylvania in the spring and early summer of 2020. Of 52 individual frogs sampled, only 5 were PCR positive for Bd, and all 5 were Rana (= Lithobates) clamitans melanota (Northern Green Frog). None of the 146 individual salamanders sampled tested PCR positive for the presence of Bd DNA. We note that the negative results may reflect an underestimation of the true prevalence of Bd at PNR because traditional PCR is not as sensitive as quantitative PCR. The generally low incidence of Bd at our site indicated that amphibians in an otherwise minimally impacted protected site are not completely immune from infection, and our results for the Northern Green Frog can serve as a baseline of general infection rates for this species in the region.