Data from: Effect of the landscape matrix on gene flow in a coastal amphibian metapopulation

Functional connectivity is crucial for the persistence of a
metapopulation, because migration among subpopulations enables
recolonization and counteracts genetic drift, which is especially
important in small subpopulations. We studied the degree and drivers of
connectivity among occupied patches of a coastal dune metapopulation of
the Natterjack Toad (Epidalea calamita Laurenti), on the basis of
microsatellite variation. As spatial landscape heterogeneity is expected
to influence dispersal and genetic structure, we analyzed which landscape
features affect functional connectivity and to what extent. Sixty
different landscape resistance scenarios as well as the
isolation-by-distance model were compared using two landscape genetics
approaches. We identified three subpopulations with unidirectional levels
of gene flow among the two most geographically separated subpopulations,
while inferred gene flow into the geographically intermediate
subpopulation was limited. Urbanization and vegetation height negatively
affected connectivity. Low estimates of genetic diversity and effective
population size indicate that conservation measures in the smallest and
most isolated subpopulation are required.