Gars: Lepisosteiformes

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GARS: Lepisosteiformes

SPOTTED GAR (Lepisosteus oculatus): SPECIES ACCOUNT

PHYSICAL CHARACTERISTICS

Gars have a long snout, or bill, and a long, armored body.

GEOGRAPHIC RANGE

Gars live in the freshwaters of eastern North America, as far west as Montana in the United States; as far north as Montana and southern Quebec, Canada; and as far south as Central America and Cuba.

HABITAT

Gars are primarily freshwater fishes, although some have been known to swim into saltwater areas near the ocean shore, such as the salt marshes of Louisiana. Gars can live in aquatic (uh-KWA-tik), or watery, environments of low oxygen content because they use their swim bladder, an internal sac usually used to control position in the water, to breathe air.

DIET

Gars eat mainly other fishes, but they also eat frogs and invertebrates (in-VER-teh-brehts), which are animals without backbones, such as crabs and crayfishes. They also sometimes eat garbage dumped into the water. Now and then they even eat other gars. Gars use their long, toothy jaws to grasp swimming prey with quick movements of their heads. Large alligator gars at times feed on water birds.

BEHAVIOR AND REPRODUCTION

Gars are sluggish but make extremely quick movements for short periods of time. They often lie motionless near the surface until prey swims within reach. Then, with a quick sideways thrust of its sharply toothed bill, the fish stabs the food animal and swallows it.

Gars spawn, or produce and release eggs, in freshwater, usually in the springtime. Fertilization (FUR-teh-lih-zay-shun), or the joining of egg and sperm, which are male reproductive cells, is external, or outside the body. Large numbers of gars come together on sandbanks for spawning and leave quickly afterward. Gars do not take care of their eggs or their young. The eggs are black and stick to rocks or plants. After hatching, the larvae (LAR-vee), or the young form of the fish, have suckers that help them stick to objects, even in moving water. The eggs are highly poisonous.

GARS AND PEOPLE

Gars are often thought of as a nuisance fish that harms game fishes, and they often break up the nets of commercial fishermen. The meat of gars is extremely bony and not generally used for food. The eggs of gars are poisonous. The bony scales of gars have been used for jewelry, arrowheads, and ornaments. Alligator gars are popular sport fishes in the southern United States and have been used in "fishing rodeos" and other tournaments. Florida gars have an attractive color pattern that makes them popular aquarium fishes.

CONSERVATION STATUS

Gars are not threatened or endangered. The gars that are thought of as harmful to game and commercial fishing receive little sympathy.

SPOTTED GAR (Lepisosteus oculatus): SPECIES ACCOUNT

Physical characteristics: Spotted gars can be as long as 44 inches (112 centimeters). They have many dark spots on the body, head, and fins. Adults have a series of small bony plates on the bottom. Females have been reported to have longer snouts than males.

Geographic range: Spotted gars live in North America from the southern shores of the Great Lakes in the north to the northern shores of the Gulf of Mexico and from northern Mexico to northwestern Florida.

Habitat: Spotted gars live in quiet, clear waters with much plant life. Some live in salty water along the Gulf of Mexico.

Diet: Spotted gars feed mainly on fishes but also may eat crabs and crayfishes.

Behavior and reproduction: Spotted gars swim slowly unless they are hunting for prey. They spawn in shallow freshwater. The newly hatched larvae have an adhesive pad on the head that allows them to adhere, or stick, to the bottom or objects on the bottom.

Spotted gars and people: People fish for spotted gars and collect them for aquariums.

Conservation status: Spotted gars are not threatened or endangered. ∎