Date of Award

5-2014

Document Type

Thesis

Degree Name

Master of Science (MS)

Legacy Department

Wildlife and Fisheries Biology

Advisor

Baldwin, Robert F.

Committee Member

Homyack , Jessica A.

Committee Member

Jodice , Patrick G.

Abstract

Understanding spatial and population ecology of organisms allows land managers to predict how changes in distribution and composition of landscape features influence persistence. Our goal was to investigate body size, sex ratios, survival, individual movements, and habitat selection of a vulnerable freshwater turtle species, the spotted turtle (Clemmys guttata), in an intensively-managed forest landscape in eastern North Carolina, USA. Spotted turtles naturally occur in wetland-dominated landscapes, but this system is heavily-altered, with >222,000 hectares of pine plantations and >10,000 km of ditches managed by Weyerhaeuser Company. During 2012-2013, we captured and individually marked 280 turtles, and used radio-telemetry (n = 31) to investigate movements and habitat selection at multiple scales. Spotted turtle monthly survival estimates were high with an annual population growth rate >1. According to a stage-based population matrix, adult and juvenile survival were the most sensitive vital rates in the population. Turtle movements and habitat selection were focused on ditch networks, which appeared to provide travel corridors between upland and aquatic sites as well as access to potential mates. At the local scale, turtles selected for greater understory closure, more pine needle substrate cover, and greater substrate temperature, suggesting scale-dependent behaviors (i.e. thermoregulation) and the importance of pine forest cover around the ditches. At the landscape scale, ditch features and middle-old aged stands were important predictors of turtle locations, which may provide important habitat for imperiled species in highly-managed forest ecosystems. Also, the persistence of spotted turtles, a vulnerable, wetland-dwelling species, in an intensively-managed upland and aquatic landscape may suggest credibility of certain management regimes given the decline of the species in more natural ecosystems.

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