Status of Blanchard's cricket frogs (Acris crepitans Blanchardi) along their decline front : population parameters, malformation rates, and disease

The most urgent amphibian conservation issue in the Upper Midwest has been Blanchard's cricket frog (Acris crepitans blanchardi) declines over much of their northern range. Several causes have been proposed to explain these declines, including pesticide applications, disease, habitat loss, and habitat modification. My goal was to explore these proposed causes. Using a combination of field and laboratory analyses, including population analyses, gross inspections for malformations, and a histopathological analysis for indicators of fungus, disease and parasites, I found evidence for disease (a viral infection) and stress (fluctuating asymmetry, malformations and parasitism). Interestingly, the population most affected by these factors was also the one that contained the most animals and was located south of the presumed decline front (i.e., was assumed to be healthy).Department of BiologyThesis (M.S.