Wetland Occupancy and Landscape Connectivity for Blanding’s and Western Painted Turtles in the Green River Valley

We surveyed all wetlands in a 9277-ha area in Lee County, IL with the intention to use occupancy and least-cost modeling to assess how landscape structure affects the distribution and population connectivity of Emydoidea blandingii (state-threatened Blanding’s Turtle) and the locally common Chrysemys picta (Western Painted Turtle). Both species are members of the Family Emydidae. Originally dominated by open marshes and sand prairie, the Green River valley in Lee County is now characterized by agricultural fields, roads, and fragmented patches of natural habitat. Surveys by the Lee County Natural Area Guardians and Illinois Natural History Survey (INHS) personnel resulted in E. blandingii captures in this area as recent as 2006. However, the current extent and status of this population was unknown. This research was conducted to (1) identify important habitat features affecting the occupancy and connectivity of the threatened Blanding’s turtle and common Painted Turtle in and around managed sand prairie habitat, and (2) assess how occupancy and connectivity patterns vary for a species of conservation concern and a closely related, abundant species in the same landscape.