Marbled rockcod

The marbled rockcod (Notothenia rossii) is a species of notothen native to the Southern Ocean, where it can be found at depths from 5 to 350 m (16 to 1,148 ft). This is a commercially important species.[2]

Marbled rockcod
Scientific classification
Kingdom:	Animalia
Phylum:	Chordata
Class:	Actinopterygii
Order:	Perciformes
Family:	Nototheniidae
Genus:	Notothenia
Species:	N. rossii
Binomial name
Notothenia rossii J. Richardson, 1844[1]
Synonyms[1]
Notothenia rossii rossii J. Richardson, 1844 Notothenia marmorata J. G. Fischer, 1885 Notothenia rossii marmorata J. G. Fischer, 1885 Notothenia coriiceps macquariensis Waite, 1916

This fish was first described in 1844 by the Scotish naturalist and explorer John Richardson who gave it the name Notothenia rossii. The specific name honors James Clark Ross, the leader of the Ross expedition, a scientific expedition by the vessels HMS Erebus and HMS Terror to survey and explore the coasts of Antarctica.[3] The marbled rockcod's range includes the northern end of the Antarctic Peninsula, the Scotia Arc, Prince Edward Islands, Crozet Islands, Kerguelen Islands, Heard Island and Macquarie Island, as well as the Ob Bank, and Lena Bank.[2]

This species can reach a length of 92 cm (36 in), though a more common length is around 50 cm (20 in). The greatest recorded weight for this species is 10 kg (22 lb). The dorsal fin is divided in two parts, with four to seven spines in the front portion and 32 to 36 soft rays in the long, back portion. The anal fin has 26 to 30 soft rays.[2]

Female become sexually mature at about six years of age. Along with mature males they move into the deeper water of the continental shelf. Spawning takes place once a year and the young fish stay mostly in shallow water in the fiords and bays, feeding mainly on zooplankton. Males can live for up to twelve years.[2]

During the 1960s and 1970s, it was heavily fished by Soviet fishers, with catches exceeding 100,000 tonnes in some seasons; it almost disappeared from around South Georgia Island, and by 1980, was depleted throughout the Southern Ocean.[4]