Language English The Gulf of St. Lawrence Photo: Biodôme Photo: Biodôme Photo: Biodôme OngletsDescriptionDistinguishing features The Atlantic mackerel has a thin, tapered body. There are 23 to 33 dark, wavy lines across the upper part of its steel blue back. Its belly is silvery white. Reproduction These fish spawn in late June in open water near the surface, at 12°C. Depending on its size, the female lays from 200,000 to 500,000 eggs. Atlantic mackerel reach sexual maturity at about 4 years. Diet These fish eat plankton, small crustaceans, fish larvae and eggs and small fish, including capelin and young herring and mackerel. Predators Their main enemies are whales, seals, sharks, tuna and gannets. Cod and squid eat the young. Habitat Atlantic mackerel live in schools on the continental shelf, on both sides of the Atlantic, at depths of 70 to 210 m. They prefer water at temperatures above 8°C. They migrate over long distances, following seasonal changes in temperatures. Ecology, behaviour These pelagic fish, which live in open water, do not have a swim bladder. This means that they have to swim constantly in order not to sink. Like the other species in their family, they are able to store heat in a network of fine blood vessels, making their muscles efficient even in cold water. French nameMaquereau bleu Scientific nameScomber scombrusPhylumChordataClassOsteichthyes (bony fish)OrderPerciformesFamilyScombridaeSizeAverage length: 36 cmWeightAverage: 0.5 kgLife span18 yearsStatusCommon species; fished commercially.