Atlantic Mackerel are members of a large family of marine fishes known as Scombridae, which inhabit temperate and tropical seas. This family includes members of the Mackerel, Jack, Bonito and Tuna species. They are also referred to as the Common, American or Boston mackerel, Maquereau Bleu(fr.), while immature or young fish are often called Tinkers.

Distribution

The Atlantic Mackerel occurs on both sides of the North Atlantic. In the western North Atlantic the mackerel ranges from Labrador in the north to as far south as Cape Hatteras, North Carolina. In Canada it occurs seasonally over the continental shelf around Newfoundland and Labrador, the Atlantic coast of Nova Scotia, the Gulf of St. Lawrence and the Gulf of Maine. It occurs less frequently in the Bay of Fundy due to colder seasonal water temperatures.

In the eastern Atlantic Ocean it ranges from Iceland and Norway, around the British Isles, the North and Baltic seas south to the North African Coast, the Mediterranean and the Black Seas.

Atlantic Mackerel are one of the smaller members of the Scombridae family, when compared to Blue Fin Tuna which reach sizes in excess of 454 kg (1000 lbs.).

Sizes can range from 25 - 40 cm(8-16 in) in length with the average size angled in Nova Scotia being 32 - 36 cm(12.5- 14 in). Reports of sizes up to 66 cm(23.5 in)have been recorded from the western North Atlantic. Average weights for this species range from 200 to 700 grams with fish more than 650 grams considered large.

The Mackerel have a streamlined body shaped for fast swimming in the open ocean. Large schools commonly travel at high speeds where some individuals can accelerate to 25-30 body lengths per second. The body is slightly compressed with a narrow caudal peduncle and deeply forked tail. There is a keel of small finlets directly behind both the soft dorsal and anal fins. The body colour is blue green on the back with 23-33 black stripes or bars along the sides from the back down to the lateral line. The undersides are silver grey to white with an iridescent sheen.

Atlantic Mackerel have no swim bladder and must swim continuously to maintain buoyancy, however this lack of a swim bladder also allows them to change depths rapidly to feed or avoid predation.
Mackerel can reach speeds in excess of 32 kph, which is necessary for survival because they are pursued by some of the fastest creatures in the sea such as porbeagle and mako sharks, porpoises, bluefin tuna, swordfish and harbour seals.
Mackerel live up to the age of 14 years, however fish 20 years old have been caught in the North Sea off Europe.
Mackerel are usually found near the surface but can be found at depths of up to 200 meters.

Natural History

Mackerel tend to be made up of individuals of similar size, since cruising speed increases with age. It is believed that a minimum size is required to maintain these speeds for extended periods of time, therefore schools are most likely made up of individuals that are the same age (cohorts) or at least the same size. Schools are constantly on the move which is probably where the saying "Mackerel are where, and when, you find them" came from.

The Atlantic Mackerel is a relatively prolific species. females can produce on average 250,000 to 300,000 eggs, however no more than 50,000 are usually released at one time as spawning can take place over several weeks. Spawning requires temperatures of 9 º C to 13.5 º C with maximum spawning occuring at 12 degrees centigrade. Eggs are spherical, transparent and contain a single globule of oil. Eggs will hatch in five to seven days at temperatures of 11 to 14 º C. On hatching, young mackerel are about 3 mm long and growth is rapid. Fish hatched in June will reach lengths of 16 to 17 cm (6.5 in) in ninety days and will reach 20 cm(8 in) by November. Some fish will be sexually mature in 2 years while most fish will be sexually mature by 4 years.

The diet of Atlantic mackerel consists of amphipods, euphausids, shrimps, crab larvae, small squid, fish eggs, and small fishes such as capelin, Atlantic silversides, young herring, smelt and mackerel. Mackerel also move through the water column to feed on plankton by filtering the micro-organisms with their gill rakers. When this type of feeding takes place at night it is sometimes accompanied by what is referred to as "firing". Firing is created by mackerel moving through schools of tiny micro-organisms that give of luminescence when disturbed. This display has been observed and reported down to depths of 30 metres(60 ft) or more.

For more information contact your local federal or provincial Department of Fisheries, or write to:

Published With Funding from the Canada-Nova Scotia Cooperation Agreement on Economic Diversification, Resource Competitiveness Program.