Atlantic Chub Mackerel, Scomber colias
Atlantic Chub Mackerel, Scomber colias. Fish caught from coastal waters off Long Island, New York, August 2022. Length: 12 cm (4.7 inches). Catch, photograph and identification courtesy of James Lafontaine, Long Island, New York.
Atlantic Chub Mackerel, Scomber colias. Fish caught from coastal waters off Manasquan, New Jersey, August 2014. Length: 13 cm (5.0 inches). Catch, photograph and identification courtesy of Eli (obsessiveangling.wordpress.com).
Atlantic Chub Mackerel, Scomber colias. Fish caught from coastal waters off Point Pleasant, New Jersey, August 2014. Length: 30 cm (12 inches). Catch, photograph, and identification courtesy of Kenneth Tse, Toronto, Canada.
The Atlantic Chub Mackerel, Scomber colias, is one of the most common members of the Mackerel or Scombridae Family, that is also known as the Atlantic Mackerel, the Chub Mackerel and the Green Mackerel and in Mexico as estornino del Atlántico. Globally, there are four species in the genus Scomber, of which three are found in Mexican waters, one in the Atlantic and two in the Pacific Ocean.
The Atlantic Chub Mackerel has an elongated, rounded, fusiform, and tuna-like body that is designed aerodynamically for speed. They are silvery with greenish tinges and oblique lines zigzagging dorsally and have paler spots or markings with wavy lines ventrally. They have large black eyes with palatine teeth in single or double rows. Their anal fin has 12 rays and is directly under the origin of the second dorsal fin, and is followed by 5 finlets; their caudal fin is deeply forked with 2 small keels separated by 1 large keel at the slender base; the first dorsal fin has 8 to 10 spines; their second dorsal fin has 12 rays, and is widely separated from the first with the distance being equal to or less than the first dorsal fin base, and is followed by 5 finlets; and, their pectoral fins are short. They have 25 to 35 gill rakers. They are covered with small scales. Their lateral line runs the entire length of the body.
The Atlantic Chub Mackerel is a coastal schooling species found from the surface to depths up to 305 m (1,000 feet). They are epipelagic to mesopelagic over the continental slope. Schools are generally segregated by size and may include various bonitos, clupeids, and jacks. They are fast growing, reaching a maximum of 53 cm (21 inches) in length and 1.1 kg (2.4 lbs) in weight. As of January 1, 2023, the International Game Fish Association world record stood at 0.74 kg (1 lb 10 oz) with the fish caught in coastal waters off New Jersey, July 2021. They are vertical migrators (diel vertical migration) that move toward the surface for feeding and return to the bottom during the day for protection. They also undergo seasonal migrations, moving to cooler waters during the summer and returning during the winters. They are opportunistic predators feeding on small pelagic fish and invertebrates. In turn they are preyed upon by billfish, sharks, tunas, and other fish and marine mammals including sea lions and various sea birds and rely heavily on camouflage for protection. Reproduction is oviparous with spawning occurring in several small batches with each female releasing between 100,000 and 400,000 eggs annually. Their eggs and larvae are pelagic. They have lifespans of up to thirteen years. The Atlantic Chub Mackerel 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 Atlantic Chub Mackerel is a resident of Mexican waters of the Atlantic Ocean but is found only in the Gulf of Mexico; they are absent from along the east coast of the Yucatán Peninsula in the Caribbean.
The Atlantic Chub Mackerel is very similar to, and can be easy confused with, the Pacific Chub Mackerel, Scomber japonicus (unmarked belly) and was only very recently separated as a different species. Otherwise it is a straightforward identification.
From a conservation perspective the Atlantic Chub Mackerel is currently considered to be of Least Concern with overall stable, widely distributed populations. However in some regions their populations have declined significantly and they are considered to be NEAR THREATENED. The Atlantic Chub Mackerel is heavily targeted commercially in the eastern Atlantic including the Mediterranean Sea and caught with purse seines (often together with sardines), gill nets, traps, and via trolling, at annual harvest levels of 3,000,000 tons.