Mexican Rockfish, Sebastes macdonaldi

Mexican Rockfish, Sebastes macdonaldi. Fish caught from coastal waters off Loreto, Baja California Sur, April 2015. Length: 30 cm (12 inches). Photograph courtesy of Chris Wheaton, Fullerton, California. Note the significant change in body depth with maturity versus the larger fish photographed below.

Mexican Rockfish, Sebastes macdonaldi. Fish caught from coastal waters off Tijuana, Baja California, February 2022. Length: 34 cm (13 inches). Catch, photograph, and identification courtesy of Chris Moore, Peoria, Arizona.

Mexican Rockfish, Sebastes macdonaldi. Fish caught from coastal waters off Loreto, Baja California Sur, October 2022. Length: 40 cm (16 inches). Photograph courtesy of Chris Wheaton, Fullerton, 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, California.

Mexican Rockfish, Sebastes macdonaldi. Fish caught from coastal waters off Loreto, Baja California Sur, May 2023. Length: 43 cm (17 inches). Photograph courtesy of Chris Wheaton, Fullerton, California.

Mexican Rockfish, Sebastes macdonaldi. A most unusual sighting of relatively small Mexican Rockfish being offered for sale by Freska Mercado, San José del Cabo, Baja California Sur, September 2019. Length: 35 cm (14 inches).

Mexican Rockfish, Sebastes macdonaldi. Fish caught from coastal waters off Loreto, Baja California Sur, April 2016. Length: 60 cm (2 feet 0 inches).

The Mexican Rockfish, Sebastes macdonaldi, is a member of the Rockfish and Scorpionfish or Scorpaenidae Family, and is known in Mexico as rocote Mexicano. Globally, there are one hundred and eight species in the genus Sebastes, of which fifty-three are found in Mexican waters, all in the Pacific Ocean.

The Mexican Rockfish has a moderately deep oblong-shaped body with a depth that is 31% to 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; and, their pectoral fins have 18 to 20 rays. They have 35 to 42 gill rakers and their body is covered with scales.

The Mexican Rockfish is found over rocky structures and are generally a sedentary bottom dwelling species. They are found at depths between 76 m (250 feet)  and 244 m (800 feet). They reach a maximum length of 66 cm (2 feet 2 inches). As of January 1, 2024, the International Game Fish Association world record stood at 4.08 kg (9 lbs 0 oz) with the fish caught in off the Nine Mile Bank in coastal waters of Baja California in February 2020. They feed on fish, krill, octopus, and a variety of other small marine organisms. They have lifespans of at least twenty years. The Mexican Rockfish is poorly studied with very limited information available about their lifestyle and behavioral patterns including specific details on age, growth, longevity, movement patterns, diet, habitat use, and reproduction.

The Mexican Rockfish is a resident of Mexican waters of the Pacific Ocean but has a limited range being found along the west coast of Baja from coastal waters off Migriño, Baja California Sur, 15 miles north-northwest of Cabo San Lucas based on a fish caught by my good friend Chris Wheaton, in March 2021, northward along the central and northwest coasts of Baja, in the central part of the Sea of Cortez, and from Guaymas, Sonora, along the coast of the mainland to Guatemala. They are one of the very few 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% to 32% of standard length).

From a conservation perspective the Mexican Rockfish has not been formally evaluated. It is 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 and on rare occasions in the fish markets in the greater Los Cabos area, Baja California Sur.