The Herpetological Journal

pp.55-63

Authors: John M. R. Baker And Tim R. Halliday

Abstract: Newly constructed ponds on farm land were surveyed for amphibians and compared with long-standing farm ponds. The frequencies of amphibian occupation of the two pond types were similar (65 and 71% respectively), but the species composition differed. Bufo bufo was found more frequently in new ponds than in old ponds, whereas Triturus cristatus and T. vulgaris were found less frequently in new ponds. The differences in the amphibian species assemblage between the two types of pond reflected the ponds' functions and the amphibians' dispersal abilities. New ponds were larger and tended to support fish and waterfowl more frequently than did old ponds. Triturus cristatus was not found in any fish ponds. Principal component and discriminant analyses of variables related to ponds and the surrounding terrestrial habitat indicated that, for T. cristatus and T. vulgaris, the location of new ponds relative to existing ponds was a significant factor in pond colonization. Triturus cristatus and T. vulgaris did not colonize ponds at distances greater than 400 m from existing ponds. Rana temporaria and Bufo bufo were not so constrained by dispersal abilities and were able to colonize new ponds at distances up to 950 m from existing ponds. Rana temporaria was more likely to be found in new ponds containing submerged vegetation; however, multivariate analyses could not discriminate between ponds that were, and were not, colonized by Bufo bufo. The results of this study are discussed with regard to the construction and management of ponds for the conservation of these amphibians.

Keywords: amphibian assemblages, farm ponds, colonization, habitat characteristics