The Tasmanian giant freshwater crayfish (Astacopsis gouldi), also called Tasmanian giant freshwater lobster, is the largest freshwater invertebrate and the largest freshwater crayfish species in the world. The species is only found in the rivers below 400 metres (1,300 ft) above sea level in northern Tasmania, an island-state of Australia. It is listed as an endangered species on the IUCN Red List due to overfishing and habitat degradation, and it has been prohibited to catch the crayfish since 1998. Giant Freshwater Crayfish are slow-growing and long-lived. They are spiny with large front pincers and their colour varies considerably among individuals, with adults ranging from dark brown-green to black or blue. The diet of the freshwater crayfish varies with age, but predominantly consists of decaying wood, leaves and their associated microbes. They may also eat small fish, insects, rotting animal flesh and other detritus when available. Juveniles tend to hide in shallow water where they are less at risk from their large predators including fish and platypuses. This species of crayfish reaches reproductive maturity late in its life. Males reach maturity at about 9 years and females do not reach maturity until about 14 years. Even after they reach maturity, females only breed every two years. They mate and spawn in the autumn and the eggs will hatch the next summer. The species is long lived and known to live up to 60 years of age and attain weights of up to 6 kilograms (13 lb), however in recent years specimens of 2โ3 kilograms (4.4โ6.6 lb) are considered large.
