SREL Reprint #2118

Structure and dynamics of a turtle community over two decades

Justin D. Congdon and J. Whitfield Gibbons

University of Georgia's Savannah River Ecology Laboratory, Aiken, South Carolina 29802

Summary: Three sequential studies of life histories and ecology of long-lived organisms have added to our understanding of age-specific biology and population ecology of freshwater turtles. Our attempt to use the long-term data from these studies to examine community levels of organization met with mixed results. Populations of Blanding's and snapping turtles were essentially stable, while the painted turtle population increased substantially over 20 years. A fourth species (stinkpot turtle) was present in low numbers but not in all years. Population dynamics of each species appeared to be independent of the other two species (i.e., no substantial levels of competitive or predator-prey relationships were indicated among species). Whether interspecific interaction would become prevalent and influential in structuring turtle communities in habitats having more turtle species, including congenerics, is yet to be determined. However, findings from the current study and from virtually all other long-term studies on turtles suggest that environmental factors or intraspecific interactions are more likely to influence turtle community characteristics than are interspecific interactions. In any case, documentation of community features among late-maturing, long-lived species is likely to become increasingly difficult due to the limited opportunities for the study of natural communities unaffected by human modification.

SREL Reprint #2118

Congdon, J.D. and J.W. Gibbons. 1996. Structure and dynamics of a turtle community over two decades. pp. 137-159 In: M. Cody and J. Smallwood. (Eds.). Long-Term Studies of Vertebrate Communities. Academic Press, Inc.

This information was provided by the University of Georgia's Savannah River Ecology Laboratory (srel.uga.edu).