The Herpetological Journal

pp.149-154

Authors: Gillian C. Baker And Trevor J . C. Beebee

Abstract: Previous laboratory and replicated pond experiments have implicated Prototheca richardsi, a unicellular alga, in interference competition within larval anuran assemblages. We investigated the extent of interspecific competition between Rana temporaria and Bufo bufo larvae, and the occurrence of P. richardsi, in small fish-ponds where initial tadpole densities were high. Mortality of both R. temporaria and B. bufo larvae was high during the early stages of development, and interspecific competition was negligible in these ponds and in mesh cages suspended in them. However, growth of B. bufo larvae was reduced when they were raised with R. temporaria larvae at natural densities in plastic cages within the ponds. P. richardsi was positively associated with the plastic cage treatments, but was much less frequent in the ponds outside or in the mesh cage treatments. Predation appears to be a much more important structuring force than either resource competition or Prototheca-mediated interference competition in the anuran communities inhabiting these fish-ponds.