Astacopsis gouldi
Tasmanian giant crayfish

This species is found in the rivers, streams, and reservoirs that drain into Bass Straight including the Arthur River System (DELM 1999).

The species can be found mostly in dark, slow moving rivers. They feed around large rotting logs and other submerged structures (DELM 1999).

Giant freshwater crayfish commonly reach 120 mm in carapace length, although they may get up to 400 mm (Bliss 1982). They do not grow to this size quickly, but can live around 30 years (DELM 1999). This is the largest known freshwater invertebrate, commonly reaching 500g and occasionally reaching 3 kg (Smithton 1999).

They have a dorso-ventrally flattened body with powerfully developed pinchers on their first set of walking legs. Their abdominal legs are longer, adapted for swimming. Females also attach their eggs to these legs (Altevogt, et al 1972).

This species of crawfish can live for 30 years because of its lack of natural predators at full maturity. The species is too large for predators such as bass which are predators of smaller species of crawfish. When hiding is needed the crawfish backs into murky banks and under submerged obstructions (IWC 1998).

The Tasmanian Giant Crayfish is omnivorous. It will harvest fungi and bacteria that grows on rotting wood that it supposedly sets aside. It eats leaves and insects that fall into the water, as well as animal flesh (IWC 1998).

This species is considered a gourmet dish in countries such as Australia. It was heavily fished for the past 20 years and is no longer allowed to be caught and eaten (Smithton 1999).

A few of the reasons for the decline of this species are its long reproductive process, loss of habitat, and the fact that it matures very slowly (DELM 1999).