Blue Rockfish
Sebastes mystinus

Physical Description

• An oval-shaped fish with a small mouth.
• Dark blue, olive brown, or grayish black coloration on back, becoming lighter on belly.
• Lighter gray blotches on sides.
• No spots on dorsal (back) fin.
• Bottom fin straight, not rounded, which distinguishes it from the black rockfish.
• Adults up to 21 inches in length.

Range

• The Bering Sea to Punta Baja, Baja California, Mexico.

Habitat

• Live on rocky bottoms, rocky shores, kelp beds, even shipwrecks.
• Found at depths of 0-300 feet, but most commonly 0-100 feet.

Reproduction

• Main spawning season is November-March.
• Fertilization is internal.
• Rockfish hatch their eggs internally and give birth to live young, which are quite small and helpless.
• A female blue rockfish can contain 500,000 eggs at a time! 

Diet

• Salps (gelatinous plankton), jellyfish, shrimp, crustaceans, small fishes, and algae.

Predators

• Juveniles are eaten by lingcod, salmonids (salmon and trout), and other larger fish.
• Adults are eaten by marine mammals like harbor seals.

Interesting Facts

• Blue rockfish are often found in large schools.
• They can live to be quite old fish, up to 44 years old! 
• This species was redescribed by Frable et al., 2015. Ben Frable is the collections manager of the Marine Vertebrate Collection at Scripps Institution of Oceanography.

Sources: California Department of Fish and Wildlife; Encyclopedia of Puget Sound; California Finfish and Shellfish Identification Book

Photo: Howard Hall