I used data from a 14 year survey of the amphibian fauna (14 species) in Jasper County, Indiana, USA, to detect population and diversity trends, and to test hypotheses regarding the influence of landscape, climatic, and biotic factors on amphibian abundance, occupancy, and diversity. Suitable amphibian habitats throughout the county were sampled by a combination of anuran call indices, density estimates, and per effort catch. The number of amphibian breeding sites, total amphibian abundance,

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... demographics of five species increased over time, while species richness/site, and mean breeding index of eight species decreased. The abundance of two species, Spring Peepers (Pseudacris crucifer) and Eastern Gray Treefrogs (Hyla versicolor), were the best indicators of overall amphibian biodiversity. Most species were associated with one or two other species. Demographics of most species were influenced by at least one climatic variable, and for most species, climatic variation among years was more important than time in explaining amphibian population trends. Winter and spring precipitation, as well as fall, winter, and spring temperatures, were the most important climatic variables influencing the abundance, occupancy, and diversity of amphibians in Jasper County. Amphibian demography and landscape data supported the hypothesis that the degree of wetland isolation and hydroperiod heterogeneity influence amphibian abundance, occupancy, and diversity. The number of wetlands in a cluster and the number of hydroperiod classes explained geographic variation in amphibian abundance, occupancy, and diversity. At the landscape level, large amphibian metacommunities were associated with large wetland clusters, hydroperiod heterogeneity, and high conservation priority upland habitats.