Widow rockfish

Sebastes entomelas, the widow rockfish, is a type of rockfish (Sebastidae) that lives mainly off the coast of western North America from Alaska to Baja California. This fish is also commonly called widowfish and red snapper.

Widow rockfish
A school of widow rockfish, Sebastes entomelas
Scientific classification
Kingdom:
Animalia
Phylum:
Chordata
Class:
Actinopterygii
Order:
Scorpaeniformes
Family:
Sebastidae
Genus:
Sebastes
Species:
S. entomelas
Binomial name
Sebastes entomelas

Description

The body of the widow rockfish is elongate and compressed. The head is relatively short, and the upper profile is slightly curved. The mouth is relatively small, the lower jaw projects slightly. The color is brassy brown over most of the body with the belly generally lighter in color, often with a reddish cast. The fin membranes, particularly in the anal and pectoral fins, are black. Specimens smaller than 10 inches (250 mm) are lighter in color and are tinged with vague streaks of orange. Widow rockfish reach lengths up to 24 inches and may live as long as 60 years, but fish older than 20 are uncommon.[1]

Habitat and Range

The widow rockfish occurs from Todos Santos Bay, Baja California, to Kodiak Island, in the Gulf of Alaska. Adult widow rockfishes are most abundant from British Columbia to northern California.

Natural history

Adult widow rockfish feed extensively on small free floating crab-like animals. Occasionally salps, small squids and anchovies are eaten. A few mature when 12 inches (300 mm) long and 3 years old. Fifty percent are mature when 12.75 inches (324 mm) long or 4 years old. Widow rockfish may live to be 16 years old. As with other rockfish fertilization is internal and the young are born live. The number of developing eggs increases from 55,000 in fish 12.75 inches (324 mm) long, to about 900,000 in a fish 20 inches (510 mm) long.

Genetics

A potential PCR-RFLP genetic sex marker developed for gopher rockfish[2] does not successfully distinguish male and female widow rockfish.[3]

Fishing information

Widow rockfish are generally caught by sport anglers fishing on or just above the bottom in deep water up to 1,200 feet (370 m), although young fish may be taken at or near the surface. On occasion, widow rockfish form huge schools in midwater where they feed on small plants. At such times, they are vulnerable to recreational anglers as well as commercial trawling gear and are often taken in great quantities.

References
  1. Fisheries, NOAA (2020-06-26). "Widow Rockfish | NOAA Fisheries". NOAA. Retrieved 2020-07-16.
  2. Fowler, Benjamin L.S.; Buonaccorsi, Vincent P. (2016). "Genomic characterization of sex‐identification markers in Sebastes carnatus and Sebastes chrysomelas rockfishes". Molecular Ecology. 25 (10): 2165–2175. doi:10.1111/mec.13594.
  3. Vaux, Felix; Aycock, Hannah M.; Bohn, Sandra; Rasmuson, Leif K.; O'Malley, Kathleen G. (2020). "Sex identification PCR–RFLP assay tested in eight species of Sebastes rockfish". Conservation Genetics Resources. 12: 541–544. doi:10.1007/s12686-020-01150-y.
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