Devastating disease can cause increased breeding effort and success that improves population resilience.

Abstract

Novel and invasive diseases are a key threat to wildlife. The disease chytridiomycosis has had devastating global impacts, but some amphibian species can persist and even rebound after severe declines. Understanding how these species persist is critical to discovering management techniques for supporting declining species. Here, we explored the impacts of disease on reproduction in the threatened Litoria verreauxii alpina, investigating its effect on reproductive effort and success using a combination of laboratory-based clinical trials and field sampling through capture-mark-recapture surveys. We found that male frogs are increasing various facets of their breeding effort resulting in increased offspring. Infected male frogs (i) increased vocal sac coloration, (ii) increased sperm quality, and (iii) fathered more egg masses than uninfected males. Our research demonstrates that frogs can counteract high disease-caused mortality through enhanced breeding effort, which could lead to population persistence. Mitigation for wildlife diseases often aims to directly reduce mortality, such as through increasing host resistance or decreasing environmental suitability for the pathogen. Our work indicates that reproductive output is also important and should be considered when protecting our precious amphibians.