The Chub Mackerel is one of the most well-known and beloved surface fish of the region. It belongs to the Scombridae family and is a close relative of the Atlantic Mackerel and the Tuna. The body is elongated and hydrodynamic like a torpedo, and it is designed to swim quickly. The back has an impressive blue-green colour with characteristic dark tiger-like stripes, though these are often more irregular and broken than those of the Atlantic Mackerel.

A very important anatomical detail affecting its behaviour is that the Chub Mackerel possesses a swim bladder, which helps fish stay buoyant. This is a major difference from the Atlantic Mackerel, which lacks one. This means the Chub Mackerel can stop swimming and hover in the water, while the Atlantic Mackerel must swim constantly to avoid sinking.

Distinguishing Features of Atlantic Mackerel

These two fish look very similar and are often sold under the same name, but they differ in two basic ways. Firstly, the Chub Mackerel has much larger eyes in relation to its head compared to the Atlantic Mackerel. Secondly and most importantly, the belly of the Chub Mackerel is never pure white but always features greyish spots or mottling, while the belly of the Atlantic Mackerel is pure silver without any markings.

This is a strictly pelagic fish that lives in the open sea, forming massive, compact schools. It usually moves at depths from the surface down to 300 metres. The species migrates constantly, and during the summer months, schools approach the coasts in large numbers to feed and reproduce, while in winter, they withdraw to deeper waters.

The animal is a voracious and opportunistic hunter. It feeds primarily on zooplankton such as copepods and small shrimp, which it filters from the water. However, larger individuals actively hunt other small pelagic fish, such as anchovies, sand smelts, and sardines, as well as the fry of other species.

Fisheries & Economic Value

The species has enormous commercial importance and is caught in large quantities with purse seines, trawls, and nets. For recreational anglers, it is a popular target using feathers or surface trolling. The meat is very delicious but also very oily and rich in beneficial Omega-3 fatty acids. Due to its fat content, it must be consumed very fresh because it perishes quickly, or it is otherwise ideal for salting or grilling over charcoal.

The International Union for Conservation of Nature classifies the Chub Mackerel as a species of Least Concern due to its wide distribution. Scientific studies have shown that its populations exhibit cyclic fluctuations related to environmental conditions and water temperature. Furthermore, research indicated that young individuals grow very quickly during the first year of life to avoid predators.