Between the Bay and a Hard Place: Altered Diamondback Terrapin Nesting Movements Demonstrate the Effects of Coastal Barriers Upon Estuarine Wildlife

Human development can impede wildlife moving between complementary habitats, particularly in highly disturbed coastal ecosystems. Coastal barriers may affect the behavior of diamondback terrapins (Malaclemys terrapin), a salt-tolerant estuarine turtle that requires access to complementary upland habitat for annual nesting. We used telemetry to quantify terrestrial and aquatic movements of 78 nesting female terrapins in response to coastal barriers at 2 sites in Barnegat Bay, New Jersey, a heavily developed estuary. Nesting female terrapins traveled significantly greater distances with more tortuous paths or spent significantly more time in the water when their movements were obstructed than females nesting at beaches with no obstructions. We hypothesize that the additional effort and displacement associated with reproduction where obstructions exist will reduce terrapin fitness and potentially contribute to population declines. Our study demonstrates a unique approach to quantifying effects of barriers on organisms requiring complementary habitats, and improves our understanding of the impacts of shoreline hardening on estuarine wildlife threatened by encroaching coastal development. (c) 2015 The Wildlife Society.