Mexican Rockfish, Sebastes macdonaldi
The Mexican Rockfish, Sebastes macdonaldi, whose common Spanish name is rocote Mexicano, 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 Mexican Rockfish have moderately deep oblong-shaped bodies with a depth that is 31 – 35% of standard length. They have a uniform dark red or maroon coloration with touches of black and are darker dorsally. Their anal, dorsal, and pelvic fins are lighter in color and their caudal and pectoral fins are dark. A key to identification is their prominent pink-red lateral line. Their anal fin has 3 spines (the second being stout and relatively short) and 7 or 8 rays; their caudal fin is concave; their dorsal fin has 12 to 14 spines and 12 to 15 rays; their pectoral fins have 18 to 20 rays; and they have 35 to 42 gill rakers. Their body is covered with scales.
The Mexican Rockfish are found over rocky structures and are generally a sedentary bottom dweller species. They are found at depths between 250 and 800 feet and reach a maximum length of 66 cm (26 inches). They feed on fish, krill, octopi, and a variety of other small marine organisms. They have lifespans of at least twenty years, however, very little is known about their behavioral patterns.
In Mexican waters the Mexican Rockfish are found along the west coast of Baja south to Todos Santos, in the central part of the Sea of Cortez, and in the Guaymas area along the coast of the mainland. They are one of a handful of Rockfish found south of central Baja.
The Mexican Rockfish is straightforward to identify due to its uniform body coloration and red-pink lateral line. It resembles the Bocaccio, Sebastes paucispinis (lacks pink colored lateral line; thinner body) and the Redstripe Rockfish, Sebastes proriger (pale red coloration; body width 28-32% of standard length).
The Mexican Rockfish are a minor component of the Southern California commercial fishery with most fish taken via gill nets and a handful being caught each year by recreational anglers. They are more plentiful in Mexican waters. They are considered an excellent food fish and can be found in the fish markets of Ensenada, Baja California.
Mexican Rockfish, Sebastes macdonaldi. Fish provided by the commercial fishermen of the greater Los Cabos area, Baja California Sur, March 2008. Length: 40 cm (16 inches). Fish identification courtesy of H.J. Walker, Jr., Scripps Institution of Oceanography, La Jolla, CA.
Mexican Rockfish, Sebastes macdonaldi. Fish caught from coastal waters off Loreto, Baja California Sur, April 2015. Length: 30 cm (12 inches). Photo courtesy of Chris Wheaton, Loreto. Note the significant change in body depth with maturity.
Mexican Rockfish, Sebastes macdonaldi. Fish caught from coastal waters off Loreto, Baja California Sur, April 2016. Length: 60 cm (24 inches).