Mitigating disease impacts in amphibian populations: capitalizing on the thermal optimum mismatch between a pathogen and its host

Abstract

Understanding how animal behavior can influence the susceptibility of endangeredhosts to emerging pathogens and using this knowledge to ameliorate negativeeffects of infectious wildlife diseases is a promising avenue in conservation biology.Chytridiomycosis, an emerging infectious disease caused by the fungal pathogenBatrachochytrium dendrobatidis(Bd) in amphibians has led to the most spectaculardisease-borne loss of vertebrate biodiversity ever recorded in history. Unfortunately, themethods of mitigation that are available today are only practical in captive populations,and an effective method that could be applied in natural habitats without inflicting vastcollateral damage is lacking. We suggest here that the thermal tolerance mismatchbetweenBdand its ectothermic hosts coupled with the thermoregulatory behaviorof amphibians could be exploited in mitigation interventions combatingBdinfectionin situ. If microhabitats with elevated temperatures are made available in their naturalenvironment, individuals taking advantage of the possibility to reach their preferred bodytemperature could critically lower their infection intensity or even clear the pathogen. Weprovide a basis for studying this approach by reviewing the evidence that supports theidea, describing how technical difficulties may be overcome, pointing out gaps in ourknowledge that need to be filled by future studies, and listing presumable benefits andprobable limitations of localized heating. The proposed approach has good potential tobecome an effectivein situmitigation method that can be easily employed in a widetaxonomic range of amphibians, especially in species that are warm-adapted, whilecausing less collateral damage than any other method that iscurrently available. If so,it may quickly become a widely applicable tool of biodiversity conservation and maycontribute to saving many amphibian populations and species from extinction in thenext few decades.