TERRESTRIAL BUFFER ZONES AND WETLAND CONSERVATION - A CASE-STUDY OF FRESH-WATER TURTLES IN A CAROLINA BAY

Because freshwater wetlands often support diverse and unique species a ssemblages, wetland loss is a primary concern in biological conservati on U.S. federal statutes protect many wetlands by deterring developmen t within delineated borders that segregate wetland habitats from uplan d regions. In addition, some state and local jurisdictions mandate buf fer zones that afford varying levels of protection to upland habitats adjacent to wetlands. We used geographic information system analysis t o test the adequacy of federal and state wetland protection statutes b y determining the degree to which protected acreage encompassed the ha bitats freshwater turtles needed to complete their life cycles. Two cr itical life-cycle stages, nesting and terrestrial hibernation, occurre d exclusively beyond wetland boundaries delineated under federal guide lines. The most stringent state buffer zone insulated 44% of nest and hibernation sites. Our data indicate that the freshwater turtles exami ned in this study required a 275-m upland buffer zone to protect 100% of the nest and hibernation sites. Insulating 90% of the sites require d a 73-m buffer zone. We suggest that the habitat needs of freshwater turtles demonstrate the dependence of wetland biodiversity on the pres ervation of adequate amounts of upland habitats adjacent to wetlands.