Scomber scombrus, commonly known as the Atlantic Mackerel, is a swift, pelagic schooling fish inhabiting the temperate waters of the North Atlantic Ocean. It forms large aggregations near the surface.
Physical Characteristics
The Atlantic Mackerel has a streamlined, torpedo-shaped body. Its back is steely-blue to greenish-blue, transitioning to silvery-white on its underbelly. Dark, wavy stripes run along its dorsal side, not extending below its lateral line.
Mature Atlantic Mackerel measure around 30 centimeters (12 inches), though some reach up to 60 centimeters (24 inches) and weigh up to 3.4 kilograms (7.5 pounds). This species lacks a swim bladder, requiring continuous swimming to avoid sinking.
Habitat and Geographic Range
The Atlantic Mackerel is widely distributed across the temperate North Atlantic Ocean. In the western Atlantic, its range extends from Labrador, Canada, southward to Cape Lookout, North Carolina. On the eastern side, it is found from Iceland and Norway to the Iberian Peninsula, and also inhabits the Mediterranean and Black Seas.
This pelagic species lives in the open ocean, typically within the epipelagic zone down to 200 meters (660 feet). Atlantic Mackerel undertake seasonal migrations, moving to shallower, coastal waters during spring and summer for spawning and feeding. As colder weather arrives, they migrate to deeper, more southern offshore waters for warmer temperatures.
Life Cycle and Behavior
Atlantic Mackerel reproduce by laying eggs near the shore during the spring and summer months. Females are batch spawners, releasing eggs multiple times throughout the spawning season. Eggs and larvae are pelagic, drifting with ocean currents.
Eggs hatch within one to six days, influenced by water temperature. Larvae develop into juveniles over three weeks, with juveniles reaching around 20 centimeters by November of their first year. Atlantic Mackerel reach sexual maturity at two to three years and can live for over 15 years.
Atlantic Mackerel form large, dense schools, often comprising thousands of individuals. This schooling serves as a collective defense mechanism against predators and enhances their efficiency when feeding. They are mainly diurnal, actively feeding during the day.
Ecological and Commercial Significance
The Atlantic Mackerel is a mid-trophic level species in marine food webs. It primarily feeds on zooplankton and small fish, contributing to the transfer of energy from lower to higher trophic levels. In turn, Atlantic Mackerel serve as a food source for a range of larger predators, including tuna, sharks, marine mammals like dolphins, and various seabirds.
Commercially, the Atlantic Mackerel is a target for fisheries across its range. Its value as a food fish is high, particularly due to its oily texture and rich concentration of healthy omega-3 fatty acids. It is prepared in various ways, commonly smoked, canned, grilled, or utilized as bait. The commercial fishery for Atlantic Mackerel in North America has existed since the 1600s.
The species’ population has been influenced by factors such as fishing pressure and environmental conditions like temperature shifts. The Atlantic Mackerel is currently listed as “Least Concern” by the IUCN Red List. However, its populations, particularly in the Northwest Atlantic, are sensitive to oceanographic changes, which can impact their growth, survival, and recruitment.