Mackerel is a common name applied to a number of different species of fish, mostly, but not exclusively, from the family Scombridae. They occur in all tropical and temperate seas. Most live offshore in the oceanic environment but a few, like the Spanish mackerel (Scomberomorus maculatus) enter bays and can be caught near bridges and piers. The largest species called "mackerel" is the king mackerel (Scomberomorus cavalla) which can grow to 66 inches (168 cm). Common features of mackerels are a slim, cylindrical shape (as opposed to the tunas which are deeper bodied) and numerous finlets on the dorsal and ventral sides behind the dorsal and anal fins. The scales are extremely small, if present. They are prized for their meat and fighting ability, and are an important recreational and commercial fishery. In the tropics, the meat can spoil quickly, causing scombroid food poisoning.

Species whose common name includes "mackerel"

Family Scombridae

• Atlantic mackerel Scomber scombrus
• Atlantic Spanish mackerel Scomberomorus maculatus
• Blue mackerel Scomber australasicus
• Broadbarred king mackerel Scomberomorus semifasciatus
• Chub mackerel Scomber japonicus
• Australian spotted mackerel Scomberomorus munroi
• Double-lined mackerel Grammatorcynus bilineatus
• Indian mackerel Rastrelliger kanagurta
• Indo-Pacific king mackerel Scomberomorus guttatus
• Island mackerel Rastrelliger faughni
• Japanese Spanish mackerel Scomberomorus niphonius
• King mackerel Scomberomorus cavalla
• Spanish mackerel scomberomorus macula

Family Trachuridae

• Atlantic horse mackerel Trachurus trachurus
• Blue jack mackerel Trachurus picturatus
• Cape horse mackerel Trachurus capensis
• Cunene horse mackerel Trachurus trecae
• Greenback horse mackerel Trachurus declivis
• Japanese horse mackerel Trachurus japonicus
• Mediterranean horse mackerel Trachurus mediterraneus
• Jack mackerel Trachurus symmetricus

Family Hexagrammidae

• Okhostk Atka mackerel Pleurogrammus azonus
• Atka mackerel Pleurogrammus monopterygius

Family Gempylidae

• Black snake mackerel Nealotus tripes
• Blacksail snake mackerel Thyrsitoides marleyi
• Snake mackerel Gempylus serpens
• Violet snake mackerel Nesiarchus nasutus
• White snake mackerel Thyrsitops lepidopoides

Species known as simply "Mackerel" in various countries:

• Atlantic mackerel Scomber scombrus
• Bigeye scad Selar crumenophthalmus
• Blue runner Caranx crysos
• Butterfly kingfish Gasterochisma melampus
• Cero Scomberomorus regalis
• Chub mackerel Scomber japonicus
• Double-lined mackerel Grammatorcynus bilineatus
• Indian mackerel Rastrelliger kanagurta
• Indo-Pacific king mackerel Scomberomorus guttatus
• Leatherjack Oligoplites saurus
• Narrow-barred Spanish mackerel Scomberomorus commerson
• Shark mackerel Grammatorcynus bicarinatus
• West African Spanish mackerel Scomberomorus tritor

Use as an adjective

"Mackerel" is also used as an adjective in the vernacular names of other types of fish, often used to indicate types with a mackerel-like pattern of vertical stripes:

• Mackerel icefish - Champsocephalus gunnari
• Mackerel pike - Cololabis saira
• Mackerel scad - Decapterus macarellus
• Mackerel shark - several species
• Sharp-nose mackerel shark - Isurus oxyrinchus
• Mackerel trevalla - Seriolella punctata
• Mackerel tuna - Euthynnus affinis