The orange roughy’s (Lat. Hoplostethus islandicus) habitat is mainly off the southwest, south, and southeast coasts of Iceland. Its distribution is from the eastern Atlantic from Iceland to Morocco, Walvis Bay, Namibia to Durban, South Afrika, the Indo-Pacific: South Central Indian Ocean and New Zealand, the eastern Pacific: Chile.
The maximum length of the fish is 75 centimetres and the greatest weight 7 kilogrammes. The oldest fish reported was 149 years old. It inhabits deep, cold waters over steep continental slopes, ocean ridges and sea-mountains. It seems to be dispersed over rough bottoms and steep, rough grounds, feeding on crustaceans and fish. Off New Zealand the main prey include mesopelagic and benthopelagic prawns, fish, and squid, with other organism, such as mysids, amphipods and euphausiids.
It grows very slowly and is among the longest lived fish species known. Based on parsite and trace-element analyses, the orange roughy is a sedentary species with little movement between fish-management zones. Little is known about the larvae and juveniles with are probably confined to deep water. The fishery targets sporadically formed dense spawning and non-spawning aggregations. Marketed fresh and frozen. Eaten steamed, fried, microwaved, and baked. Because of severe overfishing, the species has been listed as threathened by the Australian government (2006).
This species is considered very vulnerable and has a doubling time of more than 14 years.