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Species Database

Sebastes melanops - Black rockfish

Black rockfish image

Geographic range:

Amchitka Island, Aleutian Islands, Alaska to Santa Monica Bay, California

Key features:

Blue background with black mottling except along lateral line, which is light blue. Lacks dark bands sloping from eye to pectoral fin.

Similar species:

Sebastes mystinus -- Blue rockfish

Habitat(s):

bay (rocky shore), bay (sandy shore), kelp forest
 

Primary common name:

Black rockfish

General grouping:

Bony fishes

ITIS code:

166727
 

Geographic Range

Range Description:

Sebastes melanops can be found from Amchitka Island, Aleutian Islands, Alaska to Santa Monica Bay, California.

Intertidal Height

Lowest intertidal height:

0 meters OR -2 feet

Highest intertidal height:

0 meters OR 0 feet

Intertidal height notes:

Young of the year Sebastes melanops can be occasionally found in tide pools.

Subtidal Depth Range

Minimum depth:

0 meters OR 0 feet

Maximum depth:

400 meters OR 1332 feet

Subtidal depth notes:

Sebastes melanops are most commonly found subtidally.

Habitats

bay (rocky shore), bay (sandy shore), kelp forest

Habitat notes:

Sebastes melanops can be found living on the bottom associated with rocky reefs or in open water over deep banks. They can live over both rocky and soft bottoms from the surface down to 400 m, though are most common in waters with depths from 13 – 100 m. Young of the year usually occupy nearshore shallow water in kelp beds, or occasionally in tide pools. As they grow older, they tend to move into deeper waters.

Abundance

Relative abundance:

Sebastes melanops is a common rockfish north of Santa Cruz, California. Their relative abundance decreases with increasing depth.

Species Description

General description:

Sebastes melanops is in the family Sebastidae, shared by all rockfishes, rockcods, and thornyheads. The genus name,Sebastes means magnificent in Greek and the species name, melanops is formed from two Greek words meaning black face.

Distinctive features:

Sebastes melanops has a deep, fusiform and compressed body. They are black to blue black, mottled with gray dorsally and dirty white ventrally. Most have a gray to white stripe along the lateral line and black spots that extend from the back onto the lower part of the dorsal fin. The headpines are weak and the symphyseal knob is weak or absent. The head between the moderately large eyes is convex and the maxilla, or upper jaw, extends to the rear of the eye. The dorsal fin is continuous, deeply notched, with incised membranes and the spiny portion is longer based. There are 13 – 14 dorsal spines and 13 – 16 dorsal soft rays. The rear profile of the anal fin is rounded or with a greater portion slanted posteriorly and the caudal fin is truncate to emarginate. There are 3 anal spines and 7 – 9 soft anal rays.

The Blue Rockfish, Sebastes mystinus, can be confused with Sebastes melanops, but it can be differentiated by its somewhat oval body, smaller eyes, upper jaw that extends to the middle of the eye and its blueish color with light blue mottling. The Dusky Rockfish, Sebastes ciliatus, also resembles Sebastes melanops but can be distinguished by its blackish-brown body with brown, green or red speckles, the medium-sized knob at the tip of the lower jaw, and the straight rear edge of the anal fin.

Size:

Sebastes melanops can grow to a total length of 65 cm and weigh as much as 4.8 kg. However, individuals over 50 cm are rare today. In fact the current average size of Sebastes melanops observed in commercial and recreational fisheries is 35 cm. Offshore and deepwater fish tend to be larger than nearshore specimens.

Natural History

General natural history:

Sebastes melanops can be found both alone and in large schools perhaps numbering in the thousands. They often school with Yellowtail Rockfish, Sebastes flavidus, Dusky Rockfish, Sebastes ciliatus, Silvergray Rockfish, Sebastes brevispinis, or Blue Rockfish, Sebastes mystinus. Sebastes melanops is likely a relatively mobile species as tagging studies have shown that some individuals may move hundreds of miles. The record movement for this species is 345 miles from Tillamook Hook, Oregon to Cape Mendocino, California.

This species has a relatively fast growth rate reaching up to 10 cm in their first year of growth. Most individuals become available to the fishery by the time they have reached three to four years of age at 25 cm. They may live up to 50 years, though their population is considered depleted due to fishing by sport and commercial fishers. Sebastes melanops has mildly venomous spines in the dorsal and anal fins that should be avoided.

Predator(s):

Predators on adult Sebastes melanops include Lingcod, Ophiodon elongatus, rockfishes, Sebastes spp., sea lions, and Pigeon Guillemots, Cepphus columba. Young Sebastes melanops are important prey species for fishes, mammals and birds. This species is an increasingly important part of the recreational catch and are also a significant part of the commercial rockfish catch from Oregon to southeast Alaska. They may be caught on handlines, longlines, by trawl or as discard by salmon trollers.

Prey:

Sebastes melanops is mainly planktivorous, feeding on small fishes such as Sandlance, Ammodytes hexapterus, Sablefish, Anoplopoma fimbria, and juvenile rockfishes. They also consume crustaceans, polychaetes, cephalopods, chaetognaths and jellyfish. Larvae feed on nauplii, invertebrate eggs and copepods.

Feeding behavior

Carnivore

September - May

Reproduction:

Female Sebastes melanops are viviparous with internal fertilization and development of embryos. Mating occurs from September to November and females usually store sperm for a few months until their eggs mature in December or January, at which time the eggs are fertilized. The young are released from January to May, with a peak in February off the California coast. The larvae are planktonic for three to six months and as such, are dispersed by currents, advection, and upwelling. Young of the year first settle into nearshore shallow waters around April or May, though major recruitment occurs from July to August. Males begin maturing at 3 years of age and females at 5 years of age.
Click on an image below to view a larger version in the SIMoN Photo Library. You will also be able to view important information on each photo such as photographer, date, caption and more.
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Eschmeyer, W.N., and E.S. Herald. 1983. A Field Guide to Pacific Coast Fishes of North America. Houghton Mifflin Company, Boston, MA. 336 p.
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Gotshall, D. 2001. Pacific Coast Inshore Fishes. Sea Challengers, Monterey, CA. 117 p.
Kramer, D.E., and V.M. O’Connell. 1988. Guide to Northeast Pacific Rockfishes Genera Sebastes and Sebastolobus. University of Alaska, Fairbanks, AK. 78 p.
Lamb, A. and P. Edgell. 1986. Coastal Fishes of the Pacific Northwest. Harbor Publishing, Madeira Park, BC, Canada. 224 p.
Love, M. 1996. Probably more than you want to know about the fishes of the Pacific Coast. Really Big Press, Santa Barbara, CA. 381 p.
State of California. 2003. California Department of Fish and Game, Marine Region, Nearshore Finfish Profiles. World Wide Web electronic publication. http://www.dfg.ca.gov/mrd/rockfish/index.html, Accessed [09/30/06].