Grass Rockfish

Grass Rockfish, Sebastes rastrelliger

The Grass Rockfish, Sebastes rastrelliger, whose common Spanish name is rocote de olivo, is a species in the Rockfishes and Scorpionfishes or Scorpaenidae Family, known collectively as escorpiónes or lapóns in Mexico. Globally, there are one hundred twenty-four species in the genus Sebastes, forty-nine of which are found in Mexican waters, all in the Pacific.

The Grass Rockfish are heavy-bodied, stubby, and spiny fish with a body depth that is 30 to 34% of standard length. They have an olive green coloration with intermittent and irregular dark brown blotches which are lighter ventrally. Their fins are similar in color to the darker portions of the body. Their heads are wide with a tapering snout. Their anal fin has three spines (the second being stout and mid-length) and six rays; their caudal fin is broad, fan-like, and rounded with a wide peduncle; their dorsal fin has 13 spines and 12 to 14 rays; their pectoral fins have 18 to 20 rays; and they have 17 to 25 short stubby gill rakers on their first arch. Their body is covered with scales.

The Grass Rockfish reside within heavy rocky structures at depths up to 180 feet; they are one of the very few shallow water Rockfish. They reach a maximum length of 56 cm (22 inches), with males and females being of similar length. They feed on bottom dwelling crustaceans and small fish. They have a lifespan of at least twenty-three years, however, very little is known about their behavioral patterns.

In Mexican waters the Grass Rockfish are found from Cedros Island northward along the central and northwest coasts of Baja.

The Grass Rockfish can be easily confused with the Brown Rockfish, Sebastes auriculatus (21 – 30 long gill rakers; dark blotch on gill cover).

The Grass Rockfish are a strong component of the California commercial fishery with most fish taken via gill nets and hook and line; the fish is retained live and sold to ethnic markets. They are also caught close to shore by recreational anglers and divers. They are considered an excellent food fish.

Grass Rockfish, Sebastes rastrelliger. Fish caught from shore in Big Sur, California, January 2011. Length: 30 cm (12 inches). Catch, photo and identification courtesy of Eli (obsessiveangling.wordpress.com). Identification courtesy of Milton Love, University of California, Santa Barbara, Santa Barbara, CA.

Grass Rockfish (1)

 Grass Rockfish, Sebastes rastrelliger. Fish provided by the commercial fishermen of the greater San Diego area, San Diego, California, October 2014. Length: 38 cm (15 inches).