King mackerel inhabit coastal waters from the Gulf of Maine to Rio de Janeiro, Brazil, and the Gulf of Mexico, and they are most commonly found from the Chesapeake Bay southward. They are found only occasionally in the upper Bay.
The adult fish has an elongated body with a narrow head and pointed snout, and appears iridescent blue-and-green dorsally with plain silver sides. Juveniles also have five or six irregular rows of bronze spots along their sides.
King mackerel are solitary surface dwellers that tend to be found near shore, often among reefs, wrecks or other underwater structures. Immature fish school, and sometimes mix with schools of Spanish mackerel of similar sizes. King mackerel are migratory, in response to water temperature, and prefer temperatures no lower than 68 degrees F.
These mackerel appear to spawn over a protracted period, with several peaks. On the Atlantic coast, larvae have been collected from May through October. Larval distribution indicates that spawning occurs in the western Atlantic off the Carolinas, Cape Canaveral and Miami. There does not appear to be a well-defined area for spawning.
King mackerel prefer to consume fish but also have been known to eat shrimp and squid.
Female king mackerel can live for up to 14 years.

The Fisheries

King mackerel support an important commercial fishery along the Gulf of Mexico and South Atlantic coasts. In recent years, they have primarily been caught commercially in south Florida and increasingly off North Carolina and Louisiana. Historically there was a small commercial fishery for king mackerel in the Chesapeake Bay, when pound nets and gill nets were introduced in the 1880s. Total commercial catch appears to have averaged 4 million pounds during the 1920s and 1930s. Commercial landings fell to 2.5 million pounds by the 1950s and increased to 8 million pounds in the mid-1970s. Since 1985 the coastal fishery has been quota managed, and catches have averaged 3.5 million pounds. Commercial landings of king mackerel and both Maryland and Virginia are insignificant, although in some years Virginia supports a small directed hook-and-line fishery.

The Spanish mackerel commercial fishery was born around 1850 along the Long Island and New Jersey coasts, and by the 1870s was well-established in the mid-Atlantic and Chesapeake Bay area. In 1880 the Chesapeake Bay area produced 86 percent of the total coastal catch of 1.9 million pounds. By 1887 this number had dropped to 64 percent, after areas of major production had changed. This trend continued, and from 1950 through 1985 Florida accounted for more than 92 percent of the Spanish mackerel commercial landings. Since 1986 Florida’s contribution to the commercial harvest has decreased due to increased landings along the south and mid-Atlantic. Total commercial landings ranged between 5 million pounds and 18 million pounds, and between 1950 and 1983 averaged around 8 million pounds. The coastal landings have been quota-managed since 1986.