Genetic structure, metapopulation processes and evolution influence the conservation strategies for two endangered frog species

The survival and continued evolution of a species is a pivotal tenet of conservation biology. Therefore, we need to understand the factors affecting survival and evolution of species to conserve them adequately. In this study I use allozyme electrophoresis to investigate the metapopulation structure and evolutionary processes that operate within the endangered frog species Geocrinia alba and G. vitellina. Genetically, G. alba and G. vitellina are highly subdivided. A number of intraspecific genetic groups can be recognised, although even within these groups there are significant differences in allele frequencies among populations. These differences imply that migration between populations is likely to be extremely restricted if it occurs at all. The intraspecific genetic patterns suggest an evolutionary history of population bottlenecks followed by range expansion. Therefore, in the short term neither species exists as a metapopulation. However, at a larger time scale, migration, extinction and recolonisation may be central to the evolution and survival of both species. Maintenance of these processes is a challenge to which conservation managers must rise for the criteria of long-term survival and evolution to be met. (C) 1997 Published by Elsevier Science Ltd.