Date of Award

8-2007

Document Type

Thesis

Degree Name

Master of Science (MS)

Legacy Department

Wildlife and Fisheries Biology

Advisor

Yarrow, Greg K

Committee Member

King , Peter D

Committee Member

Frederick , James R

Committee Member

Bridges, Jr. , William C

Abstract

A mark-recapture study was used to examine aspects of freshwater turtle ecology, including the size at maturity, sex ratio, growth, sexual size dimorphism and ectoparasite infestation, on the Upper-Coastal Plain of South Carolina at Pee Dee Research and Education Center (PDREC). Turtles were trapped at 8 sites in Dargans' Pond during the summers of 2002, 2004, 2005 and 2006 for a total of 279 trap nights and at 6 sites in the smaller ponds at PDREC for a total of 120 trap nights during the summer of 2006. In Dargans' Pond there were 548 captures of Trachemys scripta, made up of 430 turtles and 67 captures of Sternotherus odoratus made up of 60 turtles. In the PDREC ponds there were 170 captures of 136 T. scripta.
The mean plastron length of T. scripta males and females was found to be significantly higher in Dargans' Pond. In Dargans' Pond and PDREC ponds male T. scripta were found to mature at a mean plastron length of 102 mm. The adult sex ratio of T. scripta (1.20) and S. odoratus (1.24) in Dargans' Pond were not significantly different from 1:1. The adult sex ratio of T. scripta in PDREC ponds was found to be significantly male-biased (1.70). In Dargans' Pond the growth rate of male T. scripta ranged from 0.79-7.84 mm/yr, while female growth rates ranged from 3.19-14.97 mm/yr. In PDREC ponds male growth rates ranged from 0.1-24.9 mm/yr, while female growth rates ranged from 4.98-36.2 mm/yr. The degree of sexual size dimorphism was assessed using a sexual size dimorphism index (SDI). For T. scripta inhabiting Dargans' Pond and PDREC ponds the SDI was found to be 1.35 and 1.36. For S. odoratus in Dargans' Pond the SDI was 1.05. The only species of leech found parasitizing turtles was Placobdella parasitica. A significant positive relationship was found between the number of leeches parasitizing T. scripta and body mass, plastron length, carapace length, and carapace width. Aspects of the life-history and ecology of freshwater turtles are discussed.

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