Pacific Sierra, Scomberomorus sierra
The Pacific Sierra, Scomberomorus sierra, whose common Spanish name is sierra del Pacifico, is one of the most common members of the Mackerel or Scombridae Family, known collectively as macarelas in Mexico. Globally, there are eighteen species in the genus Scomberomorus, five of which are found in Mexican waters, three in the Atlantic and two in the Pacific.
The Pacific Sierras have elongated fusiform strongly compressed bodies. They are bronze-green to bluish-black dorsally and transition to silver-white ventrally. Their sides have three to eight rows of small round orange spots, the majority being below the lateral line. Their anal fin is white; the outer half of their first dorsal fin is black; their second dorsal fin, set close to the first dorsal fin, is yellowish with a black margin; and their pectoral fins are dusky. They have a short snout. Their mouth is equipped with a set of strongly compressed teeth that are triangular and knife-like. Their anal fin has 16 to 21 rays followed by 7 to 10 finlets and their dorsal fin has 15 to 18 spines and 16 to 19 rays followed by 7 to 10 finlets. Their pelvic fins are relatively long. Their caudal fin base has two small keels separated by a larger third keel. They have 12 to 17 gill rakers. Their body is covered with small scales and their lateral line gradually curves down to the caudal fin base.
The Pacific Sierras are a coastal pelagic schooling species found from the surface to depths up to 15 meters (50 feet). They reach a maximum of 1.12 meters (3 feet 8 inches) in length and 8.2 kg (18 pounds) in weight. They prefer water temperatures of less than 23oC (74oF). Spawning occurs in coastal waters and smaller fish reside around sandy beaches very close to shore while larger adults are found in deeper waters on the continental shelf. They are voracious predators and consume small fish including anchovies, clupeids, and herrings. Very little is known about their reproductive and behavioral patterns.
In Mexican waters of the Pacific the Pacific Sierra are found in all waters of the Pacific.
The Pacific Sierra is easy to recognize, thus is not easily confused with any other species from the Pacific with the possible exception of the female Gulf Sierra, Scomberomorus concolor from the Northern Sea of Cortez (two rows of yellow spots; 21 to 27 gill rakers). It is virtually identical to, and indistinguishable from, the Spanish Mackerel, Scomberomorus maculatus, found in the Atlantic.
The Pacific Sierras are a seasonal target of commercial and recreational anglers along the Pacific Coasts of Mexico and Central America. They are the most abundant game fish in tropical coastal waters of the Eastern Pacific during the cooler months when colder water is present. They are caught with a wide variety of natural baits and artificial lures but the use of a wire leader is required. They are a great foe on light tackle. Trying to land these fish without a wire leader is a great sport. Commercially they are caught with gill nets by artisanal fishermen at catch levels approaching 15,000 tons per annum, although a recent reduction in catch levels has been reported. They are considered an excellent food fish being marketed fresh and frozen and also used for ceviche. They do however have a very short shelf-life and must be put on ice immediately upon collection and consumed the same day they are caught. Approximately 5% of the population contains a parasite that is readily apparent in fillets. I recommend that this fish be discarded and not consumed. From a conservation perspective they are currently considered of Least Concern with stable populations. Throughout their range they have only limited protection, which is mostly directed at recreational fishermen with a 10-fish daily bag limit in Mexico and a minimum catch length in Peru.
Pacific Sierra, Scomberomorus sierra. Fish caught from coastal waters off Point Palmilla, Baja California Sur, February 2016. Length: 42 cm (17 inches).
Pacific Sierra, Scomberomorus sierra. A fillet contaminated with an unknown parasite. Note: By appearance, this is the same parasite found in the fillets of the Pacific Porgy, Calamus brachysomus, and I do not recommend the human consumption of a fish with this contamination.