Butterfishes and Relatives: Stromateoidei

Physical characteristics: Butterfish are about 12 inches (30 centimeters) long. The body is narrow from side to side and broad from back to belly. The single long dorsal and anal fins are tall and pointed near the front and taper toward the rear. The pectoral (PECK-ter-uhl) fins, the pair that corresponds to the front legs of four-footed animals, are long. The tail fin is deeply forked. There are no pelvic fins. The fish's back is grayish blue. The sides are silver with dark spots.

Geographic range: Butterfish live in the western part of the Atlantic Ocean and in the Gulf of Mexico.

Habitat: Butterfish live in open water or on the bottom, usually over sand. They may enter shallow bays and estuaries (EHS-chew-air-eez), or the areas where rivers meet the sea.

During their first year butterfish may live among jellyfishes or swim freely, but they form schools as adults. (Illustration by Dan Erickson. Reproduced by permission.)

Diet: Butterfish eat sea squirts, mollusks, and small crustaceans. Mollusks (MAH-lusks) are animals with a soft, unsegmented body that may or may not have a shell. Crustaceans (krus-TAY-shuns) are water-dwelling animals that have jointed legs and a hard shell but no backbone.

Behavior and reproduction: Butterfish are active day and night. During their first year these fish may live among jellyfishes or freely, but they form schools as adults. Butterfish can reproduce when they are one or two years old. They spawn once a year, scattering their eggs, which drift in open water.

Butterfish and people: Butterfish are important food fish.

Conservation status: Butterfish are not threatened or endangered. ∎