The size of king mackerels range from 5 to 30 lbs, but some species can go over 90 lbs. The smaller ones (under 10 lbs / 5 kg) are distinguished by the yellow brown marks at the flanks. The fish is usually found in waters 40 to 150 feet (12–45 m). However, the bigger ones (20 lbs / 9 kg) can be found inshore. Sometimes these large types are found in 600 ft deep waters.
The fertilized eggs will hatch within a day. The new larva will measure 0.1 inches (2.5 mm) long. The average yearling fish will weigh 3 to 4 lbs (1.4–1.8 kg). The fork length will be 25 inches (60 cm).
By seven years of age, the males will weigh 11 lb (5 kg) and females 21 lb (9.5 kg). The various sizes of king mackerels show that on the average, females are bigger.
The body is layered with tiny scales. The color of the back is olive, but the back slowly changes to silver on the way to the tail. The sides are reddish but changes to white when it gets to the belly. The fish has large teeth.
In terms of the appearance, the smaller king mackerel looks like the Atlantic Spanish mackerel. Another fish that bears a strong resemblance to it is the Serra Spanish mackerel.
The species are found in the Atlantic Coast. They are very prevalent by the coastlines of Brazil and North Carolina. The species prefer temperatures of 68 to 85 °F (20 to 29 °C). There are two migratory groups.
There is a group from the coast of Texas up to the Florida coast. The other migratory group is off North Carolina. They proliferate during autumn and spring.
Whatever the size of king mackerels, they all share common feeding behaviors. They are opportunistic by nature. This means the king mackerel will feast on prey that is commensurate to its size. Many of them however, like menhaden, weakfish, cutlassfish, striped anchovies, grunts and threadfin.
The king mackerel is one of the most popular species of game fish in the Americas. Many types of fishing gear are used to take the fish. The methods include trolling, jigs, spoons, dead baitfish and various types of artificials.
Commercially they can be taken by heavy tackle or trolling. If live bait is used, a couple of hooks should be fastened to a steel leader. Its popularity as sport fish is indicated by the many groups that are sponsoring events with the species.
As Marketed Fish
The king mackerel is sold fresh. They are usually sold as steaks, whole or fillets. The uncooked flesh has a grey color. This is due to the fats inside. There are many ways to cook the fish, including baking, frying, broiling and smoking. The smoking method is very popular for the larger species.
It should be stressed that the size of king mackerels during the first year is not clear. The size usually given is based on the size of fish similar to the king mackerel.