Sablefish

Sablefish, Anoplopoma fimbria

The Sablefish, Anoplopoma fimbria, whose common Spanish name is bacalao negro, is a member of the Sablefish or Anoplopomatidae Family, collectively known as bacalaos negros in Mexico. This fish is also known as the Black Cod. Globally, this family only has two species which have been placed in two genera. This fish is the only species in the genus Anoplopoma and is found only in Mexican waters of the Pacific.

The Sablefish have large, elongated, robust, fusiform bodies that taper toward the tail. Juveniles that measure less than 15 cm (6 inches) are black dorsally, white ventrally, and blue on their side. Young adults are greenish with faint stripes on their back. Adults are dark olive green dorsally with pale blotches or chain-like patterns on their upper back, which are paler ventrally. There is a limited number of Sablefish that are albino, solid yellow, or another color. They have a large head, a gradually tapering snout, and modest sized eyes. Their mouth ends at the front margin of the eyes. Their anal fin has 3 spines and 15 to 19 rays and their caudal fin is forked with deep lobes. Their dorsal fin has 19 to 27 spines and 16 to 20 well-separated rays; the second part is equal to or slightly smaller than the anal fin and in the opposite position. Their pectoral fins are short and wide and their pelvic fins are slightly ahead of the pectoral fins. They have 62 to 65 gill rakers. They have a single continuous lateral line that runs the entire length of the body. They are covered with small scales.

The Sablefish are a demersal species with a migratory lifestyle found over a variety of habitats but primarily over muddy bottoms. Juveniles between four and six years of age remain in shallow coastal waters then migrate offshore to depths as great as 9,000 feet where they prefer oxygen deprived waters with temperatures of 2.0oC (36oF) to 12.6oC (55oF). Larger fish are found in deeper waters and in the northern part of their range. Females are larger (117 cm versus 91 cm) and live longer (94 years versus 68 years) than males and can reach 57 kg (125 pounds) in weight. They consume crustaceans, cephalopods, and other small fish. They are preyed upon by Pacific Cod, Pacific Halibut, Spiny Dogfish, Elephant Seals, Harbor Seals, California Sea Lions, Orcas, and Sperm Whales. Reproduction is oviparous but occurs in very deep waters and is not well understood. Each female releases between 51,000 and 1.3 million eggs per annum and the eggs and larvae become buoyant and migrate to coastal shallow waters. This species is slow-growing and long-lived.

In Mexican waters the Sablefish have a limited distribution being found from Guerrero Negro northward along the central and northwest coasts of Baja.

The Sablefish is straightforward to identify and cannot be confused with any other species.

The Sablefish are prized commercial fish with a high fat content and sold extensively on a global basis. They have been harvested via long-line, trawls, and in traps for more than 100 years. Due to the high demand and excessive fishing pressure, commercial fishermen are now required to have permits and specialized gear; respect quantity limits, depth, and seasonal area closures; and log and report trip and catch quantities. In California waters, they are caught at a level of 1,900 tons (4.2 million pounds) valued at $6.2 million per year and are heavily exported to Japan. Due to their depth migration as they mature, only limited numbers of juveniles are caught by recreational fishermen. They are marketed live, fresh, frozen, dried, and smoked. They can be steamed, pan-fried, broiled, or microwaved for human consumption and have a buttery flavor. They are also a valuable source of Vitamin A and Vitamin D. From a conservation perspective they have not been evaluated although they are heavily regulated and their catch levels are heavily monitored.

Sablefish, Anoplopoma fimbria, Juvenile. Fish caught from coastal waters off Sitka, Alaska, May 2015. Length: 25 cm (10 inches). Catch, photo, and identification courtesy of Chris Wheaton, Loreto, Baja California Sur.

Sablefish, Anoplopoma fimbria. Fish caught from coastal waters off Sitka, Alaska, May 2015. Length: 43 cm (17 inches). Catch, photo and identification courtesy of Chris Wheaton.

Sablefish (3)

Sablefish, Anoplopoma fimbria. Fish provided by the commercial fishermen of the greater San Diego area, April 2016. Length: 40 cm (16 inches).