Fungal pathogen infection intensity associated with reproductive mode and elevation in an afrotropical anuran community

Abstract

The effects of host ecology and environmental conditions on infection dynamics of the amphibian chytrid fungus Batrachochytrium dendrobatidis (Bd) have been documented in several tropical and montane regions across the globe. These interactions are often complex and unique at local scales. Data on the historical and current chytridiomycosis-amphibian system is largely lacking in Africa, especially central Africa. We conducted the first survey of Bd in continental Equatorial Guinea in 2019, and extensively sampled the land-bridge island, Bioko, in 2011 and 2019. Our results provide novel information on the distribution and prevalence of Bd in Equatorial Guinea and demonstrate the effects of host developmental mode and elevation on Bd infections. We found that Bd infection loads are positively linked with elevation and that direct-developing species have higher average Bd loads than aquatic breeding species at all elevations. These patterns corroborate previous findings in afrotropical amphibian assemblages. Additionally, our study confirms the presence of Bd in continental Equatorial Guinea, providing updated information on the distribution of Bd in central Africa, and confirming the need for careful monitoring of this biodiverse region.