PURRENHAGE, J.L.*; NIEWIAROWSKI, P.H.; MOORE, F.B.-G.; ZAMUDIO, K.R.; Univ. of Akron; Univ. of Akron; Univ. of Akron; Cornell University: Regional population dynamics of spotted salamanders (Ambystoma maculatum) in a fragmented landscape

Metapopulation theory provides a framework for predicting population persistence and other population dynamic behavior when populations in a given landscape are connected by dispersal. Although many species of amphibians, especially those breeding in ephemeral ponds, are presumed to exist as metapopulations, there are precious few data demonstrating metapopulation structure of any amphibian. Nevertheless, there is much current interest in understanding landscape-level processes in terms of their impacts on the population biology of amphibian species. Most amphibians are cryptic in their terrestrial home ranges; therefore, indirect methods of measuring rates of individual dispersal provide an opportunity to construct realistic metapopulation models for many species. At the very least, metapopulation processes can only be reliably modeled once we have information about rates of movement of individuals among populations. We are interested in the role that metapopulation processes and landscape-level habitat variation contribute to the population dynamics of spotted salamanders (Ambystoma maculatum) in northeastern Ohio. We utilized 8 microsatellite loci to determine the genetic structure of spotted salamanders breeding at 17 ponds located within a landscape fragmented by roads, agricultural and urban areas, and the Cuyahoga River. Dispersal of individuals among populations influences gene flow and thus contributes to genetic differentiation among ponds. Using a variety of analyses (e.g., F_ST, BAPS, AMOVA) we uncovered interesting patterns of genetic structure that are not predicted by geographic interpond distances or landscape features believed to inhibit dispersal.