Genetic diversity and population structure of the threatened freshwater catfish, Tandanus tandanus, in Victoria, Australia

In Australia, many species of freshwater fish have rapidly declined following European settlement in the late eighteenth century. The freshwater catfish (Tandanus tandanus) is listed as threatened in Victoria and accordingly, broodstock management and a captive breeding program to facilitate the reintroduction of hatchery bred fish into depleted populations have been suggested. Little work has been conducted on Victorian populations of T. tandanus, despite its threatened status. This study assessed the genetic diversity and genetic structure of T. tandanus in Victoria, using mitochondrial and microsatellite markers. Genetic diversity of T. tandanus in Victoria varied greatly between sites, with the Mallee containing the highest diversity at both markers. Sites where T. tandanus had been introduced in the past typically contained lower measures of genetic diversity, with the exception of the Wimmera site for microsatellite markers. Populations could be assigned to one of four broodfish z...