Blue rockfish
(Sebastes mystinus)
General data
The blue rockfish (Sebastes mystinus) or blue seaperch, is a species of marine ray-finned fish belonging to the subfamily Sebastinae, the rockfishes, part of the family Scorpaenidae. It is found in the northeastern Pacific Ocean, ranging from northern Baja California to central Oregon.
Description
Blue rockfish have a relatively smooth and oval appearance compared to other members of Sebastes, with very few head spines. Color is a bluish black to gray, with some darker mottling, including a pair of stripes angling down and back from the eye. The terminal mouths are small for rockfish. Length ranges up to 55 to 60 cm, and weights up to 3.8 kg.
Ecology
Blue rockfish seem to be adapted to diurnal hunting on small, transparent plankton. Juveniles consume tiny crustacea such as copepods and barnacle larvae (in some cases having a significant effect on the population), while adults shift to larger types, such as free-swimming tunicates, jellyfish, gastropods, squids, young rockfish, and drifting plant fragments.
Distribution
Blue rockfish occur from northern Baja California to central Oregon. Previous records further north are due to confusion with the deacon rockfish (S. diaconus), which was described as a separate species genetically and scientifically in 2009 and 2015, respectively.
While they have been caught at depths of over 500 m, most live near to the surface, down to 90 m.
