Evaluating Wetland Conservation Policies
with GIS Models of Habitat Use by Aquatic Turtles
— A B S T R A C T OF P R E S E N T A T I O N * —
VINCENT J. BURKE 1, 2 and J. WHITFIELD GIBBONS 1
1 Savannah River Ecology Laboratory, University of Georgia, Drawer E, Aiken, SC 29802, USA
2 Current address: 302 ABNR, School of Natural Resources, University of Missouri,
Columbia MO 65211, USA / e-mail: snrburke@showme.missouri.edu
A variety of organisms depend upon freshwater wetlands for all or part of their life cycle. In the absence of wetlands, both upland and lowland ecosystems support vastly different and often less rich species assemblages. For these reasons, the loss of wetland acreage has become a primary concern in biological conservation. Current federal statutes in the United States protect many wetlands by deterring development within an officially delineated border between the aquatic and terrestrial habitats. We tested wetland boundaries by using a geographic information system model to define the land use activities of three species of freshwater turtles (Kinosternon subrubrum, Pseudemys floridana, and Trachemys scripta). Our results indicate that 100% of two critical life-cycle functions, nesting and terrestrial hibernation, occur exclusively beyond the federally delineated boundary. The most stringent state statute (i.e., Massachusetts) would have provided a 100 foot (30.49 m) buffer encompassing 44% of nest and hibernation sites (n = 93 nests, 24 hibernation sites). Total protection of the sites required a 275 m buffer beyond the federal wetland boundary. Excluding the most distal 10% of sites resulted in a buffer that extended 73 m beyond the federal delineated boundary. We suggest that without biologically based buffer zones, current and proposed wetland policies may postpone, but will not prevent, extirpation of turtles and other semi-aquatic wetland species.
* Published Paper:
Burke, V. J. and J. W. Gibbons. 1995. Terrestrial buffer zones and wetland conservation: A case study of freshwater turtles in a Carolina bay. Conserv. Biol. 9(6):1365–1369.
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