Theses (M.S.)--Marshall University, 2007. / Title from document title page. Includes abstract. Document formatted into pages: contains viii, 75 pages including illustrations and maps. Bibliography: p.72-73.

During 1984-85 I investigated population ecology and habitat relationships of river cooters (Pseudemys concinna) in the New River Gorge National River (NRGNR), West Virginia. Cooter colonies occurred in 3 pool habitats characterized by slow current velocities (x=0.22m/s), shallow water (0-2m), aquatic macrophyte beds, and basking sites. The estimated adult population during summer 1985 was 64 individuals. Six, 25%, and 35% of the captures at the three study sites respectively, were juveniles. Most hatchling cooters apparently overwintered in the nest and emerged in April. Juvenile growth was rapid and linear until 6 years of age. Adult female cooters were larger (P=0.03) and heavier (P=0.0004) than males. Adult cooters consumed mostly eelgrass (Vallisneria americanaElodea canadensis), although some crayfish remains were found in fecal samples. Juveniles consumed vegetation as well as invertebrates and fish. Cooters did not move out of the pool habitats in which they were marked. Movements within pool habitats were influenced by basking site availability and location, which varied with river flow fluctuations. Two radio-marked cooters wintered in shallow backwater channels. Potential factors limiting the population are collecting and high artificial summer flows which scour weed beds. Addition of basking sites may increase habitat suitability for cooters. / Master of Science

The phylogeny of the turtle genus Pseudemys is poorly understood. In Virginia, many turtles have been found with indicator traits of both eastern river cooters (Pseudemys concinna concinna) and northern red bellied cooters (Pseudemys rubriventris). This study explores morphological evidence for hybridization between the two species across three riverine sites in east central Virginia. Museum voucher groups for each species were analyzed for relative shell height and plastron length. The shape of the plastral scutes and upper jaw were analyzed using landmark-based morphometric software. These metrics were compared with measurements taken from 188 field-caught Pseudemys specimens. Across phenotypic metrics, field specimens resembled northern red bellied cooters. Geometric morphometric analysis showed extreme variation. Thirteen field specimens exhibited indicator traits of both species. Because species boundaries do not appear to be well-resolved using accepted phenotypes and morphometrics, we suggest that additional research utilizing molecular methods and genetic analysis be conducted.

Thesis (M.S.)--Texas State University-San Marcos, 2008. / Vita. Includes bibliographical references (leaves 22-25). Also available on microfilm.