Anuran call surveys on small wetlands in Prince Edward Island, Canada restored by dredging of sediments

Abstract

In 1990, the North American Waterfowl Management Plan (NAWMP) implemented a small-wetland restoration program in Prince Edward Island (PEI), Canada. Wetlands were restored by means of dredging accumulated sediment and organic debris to create open water and emulate pre-disturbance conditions. Three call surveys were conducted in the spring and summer of 1998 and 1999 to estimate abundance and occurrence of spring peepers (Pseudacris crucifer), wood frogs (Rana sylvatica), northern leopard frogs (Rana pipiens), American toads (Bufo americanus), and green frogs (Rana clamitans) on restored and reference wetlands. Numbers of species calling and abundance indices of northern leopard frogs green frogs and spring peepers were significantly higher on restored versus reference wetlands. The number of species calling in restored wetlands was positively correlated with proximity to freshwater rivers; in reference wetlands, the number was positively associated with forested perimeters and area of open water. Occurrence of calling green frogs in restored wetlands was positively correlated with percent cattail and, in reference wetlands, with proximity to other wetlands. Our results suggest that small wetland restoration projects may be a good conservation tool for anurans. We recommend further research on reproductive success and on local population trends in restored wetlands to determine if restoration is beneficial for anurans on PEI.