The conservation status of Tasmanian freshwater crayfish

Tasmania supports a diverse crayfish fauna, with four genera: Geocharax (1 species), Engaeus (15 species, 13 endemic), Astacopsis (endemic genus, 3 species), and Parastacoides (endemic genus, 14 species). These include the world's largest crayfish, some of the most terrestrial crayfish and species adapted to naturally high levels of soil acidity. One introduced species, Cherax destructor, has been recorded. Three crayfish species (Engaeus yabbimunna, Engaeus spinicaudatus and Astacopsis gouldi) have been listed as Vulnerable under the Tasmanian Threatened Species Protection Act 1995. A soon-to-be described species of Parastacoides is likely to be placed on the Vulnerable list and eight other species meet the criteria for Rare. Astacopsis gouldi is threatened by overfishing and habitat degradation; in January 1998 fishing for this species was banned. Engaeus spinicaudatus and Engaeus yabbimunna have restricted distributions and are subject to various levels of habitat disturbance. Their ranges have almost certainly been reduced since European settlement, but recent observations have extended the range of E. yabbimunna into three new catchments. A revision of Parastacoides has identified several species with restricted distributions. One of these meets the criteria for Vulnerable, and another six species are Rare.