Fish of the Week: Atlantic Mackerel

[This content recycled from my now mothballed website, excitablemedia.com.]

Its ironic that of all the fish in the sea the mackerel was chosen to express surprise or wonder. Simply put, there is nothing particularly surprising or wonderful about the mackerel.

Mackerels are classified in the phylum Chordata, subphylum Vertebrata, class Osteichthyes, order Perciformes, family Scombridae.

[The Atlantic Mackerel looks like this.]

They are characterized by deeply forked tails that narrow greatly where they join the body; small finlets behind both the dorsal and the anal fins; and sleek, streamlined, sexy bodies with smooth, almost scaleless skins having an iridescent sheen. All members of the mackerel family are superb, swift swimmers. The firm, oily texture of their powerful muscles and their generally large size make them of great commercial importance as food fish.

Helpful Hint: ho'ly mack'erel
Slang. Used as an exclamation to express surprise or wonder.

Mackerel spawn in open water during late spring and early summer. The eggs are laid primarily at night and float on the surface.

On average, Atlantic Mackerel weigh less than one pound, but up to two pounds is not unusual. The largest Atlantic Mackerel ever caught on rod and line was in 1995, from deep water off the western Swedish coast. It weighed 6 lb 13 oz.

Young mackerel feed on microscopic copepods. As they grow, they feed on progressively larger prey. Adults will eat any fish smaller than themselves, feeding heavily upon small herring, sand lance and (cannibalistically) young mackerel.

The Atlantic Mackerel is typically an open ocean fish with voracious feeding habits. All individuals within a specific school tend to be the same size. Since cruising speed increases significantly with age and size, scientists believe that peer-pressure-induced conformity of body size within a specific school is necessary to allow all fish to maintain identical swimming speeds.

Atlantic Mackerel are long-lived fish, that is, if they are not caught. Fish of over 25 years old have been caught in the North Sea. Despite its size, the annual catch is 50 million lb, which is marketed fresh, salted, and canned. When freshly caught, the mackerel makes excellent eating, but the fishy flesh deteriorates rapidly.