Shortraker rock-fish

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Sebastes borealis

Kingdom:	Animalia
Phylum:	Chordata
Class:	Actinopterygii
Order:	Scorpaeniformes
Family:	Sebastidae
Genus:	Sebastes Cuvier, 1829
Species:	S. borealis

Binomial name

Sebastes borealis

Shortraker Rock-fish (Sebastes borealis) is an offshore, demersal species distributed from the southeastern Kamchatka Peninsula, Russia, to Ft. Bragg, California (Kramer and O'Connell, 1986). It attains lengths greater than one meter (>39 inches) and weights to 20 kg (44 pounds). In the Gulf of Alaska, shortraker rockfish are sampled annually during longline surveys and are most abundant between depths of 300 and 400 m (984 and 1,312 feet).

Commercial harvesting of shortraker rockfish in the Gulf of Alaska began in the early 1960's when foreign trawl fleets were targeting more abundant Sebastes spp. In recent years, high catch rates of shortraker rockfish indicate that the domestic trawl fleet targets this species; shortraker rockfish comprised 14.9% of the species composition of slope rockfish harvested in 1990, although trawl survey data indicates they comprised only 2.5% of the biomass (Heifetz and Clausen, 1991).

In 1991, catch limits were established for shortraker rockfish to prevent overharvesting of this species in the Gulf of Alaska. Catch limits are based on biomass estimates derived from bottom trawl catch rates. These biomass estimates are questionable, however, because the catch efficiency of bottom trawls on shortrakers is unknown. Fishermen report that shortrakers school off-bottom and above rugged habitat in steep-slope areas where bottom trawls cannot sample effectively.^[1]

In 2007 fishermen caught a specimen that was studied and estimated to be between 90 and 115 years old. It was caught south of the Pribilof Islands at an estimated depth of 2,100 ft (640 m).^[2] The oldest recorded shortraker caught was 157 years old.^[3]^[4]