WEEVERFISHES AND RELATIVES: Trachinoidei

PHYSICAL CHARACTERISTICS

Weeverfishes and their relatives are only loosely related to one another, so they do not have many physical characteristics in common. They can be about 2 inches (5 centimeters) to about 30 inches (76 centimeters) long. Some have snakelike bodies, and some have a familiar "fish" shape. Some have a large mouth with huge teeth. Some have no scales. Some have light-producing organs. Some have electric organs. Some have eyes on the tops of their heads and a venomous spine on the gill cover. Some have two dorsal fins and some only one very long dorsal fin. Some have one short and one long dorsal fin. Most have long anal fins. Some have large pectoral fins. The dorsal (DOOR-suhl) fin is the one along the midline of the back. The anal (AY-nuhl) fin is the one along the midline of the belly. The pectoral (PECKter-uhl) fins correspond to the front legs of four-footed animals.

GEOGRAPHIC RANGE

Weeverfishes and their relatives live in the Arctic, Atlantic, Indian, and Pacific oceans. One species lives only in New Zealand.

HABITAT

Most weeverfishes and their relatives live in the sea close to shore and in estuaries (EHS-chew-air-eez), or the areas where rivers meet the sea, on sandy to muddy bottoms. Some live in burrows under coral. Others live in the deep ocean. Some hug the bottom of fast-flowing freshwater streams.

DIET

Weeverfishes and their relatives eat fishes, animal plankton, small crustaceans, and worms. Plankton is microscopic plants and animals drifting in water. Crustaceans (krus-TAY-shuns) are water-dwelling animals that have jointed legs and a hard shell but no backbone.

BEHAVIOR AND REPRODUCTION

Most weeverfishes and their relatives live alone. Some form schools of hundreds to several thousand fish. Some weeverfish relatives hide in the sand or mud and suck in their prey, or animals hunted and killed for food. Others chase down their prey. Some fishes in this group are active during the day; others, at night. Some move from deep water to the surface at night. Scientists know little about the reproduction of weeverfishes and their relatives. Some fishes change sex from female to male. Most probably scatter their eggs, which sink to the bottom.

WEEVERFISHES AND THEIR RELATIVES AND PEOPLE

Only a few weeverfishes and their relatives are caught and sold for food. Some are caught for fishmeal and oil. People can be injured if they step on the sharp spines of weeverfishes and stargazers.

DID YOU KNOW?

The name "weeverfish" probably comes from the Anglo-Saxon word wivere, which means "viper." Weeverfish venom causes severe pain and sometimes fever, vomiting, and heart failure.

CONSERVATION STATUS

The World Conservation Union (IUCN) lists one species of weeverfishes and their relatives as Endangered and one species as Vulnerable. Endangered means facing a very high risk of extinction in the wild. Vulnerable means facing a high risk of extinction in the wild.

INSHORE SAND LANCE (Ammodytes americanus): SPECIES ACCOUNTS

Physical characteristics: Inshore sand lances are long and thin. They have no teeth, and the lower jaw juts far beyond the upper jaw. The dorsal and anal fins are very long. Tiny folds of skin all along the body have smooth scales underneath them. The body is olive, brownish, or bluish green on top with silvery sides and a white belly. These fish grow to a length of about 6 inches (16 centimeters).

Geographic range: Inshore sand lances live on the Atlantic coast of North America.

Habitat: Inshore sand lances burrow in sand or gravel in shallow water along the coast and in estuaries.

Diet: Inshore sand lances eat animal plankton.

Behavior and reproduction: Inshore sand lances form schools of up to several thousand fish. At high tide they burrow into the sand and remain there until the next tide. Scientists have never observed inshore sand lances spawning. These fish can reproduce when they are about two years old. They release eggs that sink to the bottom and hatch into freely swimming larvae (LAR-vee), or animals in an early stage that must change form before becoming adults. Inshore sand lances live about twelve years.

Inshore sand lances and people: Inshore sand lances have little direct importance to humans. They are important as food for fish that are caught and sold.

Conservation status: Inshore sand lances are not threatened or endangered. ∎

NORTHERN STARGAZER (Astroscopus guttatus): SPECIES ACCOUNTS

Physical characteristics: Northern stargazers have a squarish head with a flattened top and a large mouth with fringed lips. The eyes are on the top of the head, and there are electric organs in pouches behind the eyes. The first of the two dorsal fins has four or five spines. The anal fin has one spine. The pectoral fins are large, and there is a spine just above each one. The fish's back is dark brown with small white spots. The belly is gray. The first dorsal fin is solid brown, and the second has black and white stripes. The pectoral fins are dark with a pale edge. Northern stargazers grow to a length of 22 inches (56 centimeters) and a weight of 20 pounds (9 kilograms).

Geographic range: Northern stargazers live on the Atlantic coast of North America from New York to North Carolina.

Habitat: Northern stargazers live on sandy bottoms in coastal waters.

Diet: Northern stargazers eat small fishes and crustaceans.

Behavior and reproduction: Northern stargazers lie buried on the bottom with only the top of the head, eyes, and mouth exposed waiting for prey, at which they lunge aggressively and suck into their large mouths. These fish release their eggs into open water. The larvae settle on sandy bottoms until they are about 8 inches (20 centimeters) long and then move farther offshore.

Northern stargazers and people: Northern stargazers are not fished for food or sport. If caught, they should be handled with care, because of the sharp pectoral spines and the electric organs.

Conservation status: Northern stargazers are not threatened or endangered. ∎

FOR MORE INFORMATION

Books:

Allen, Missy, and Michel Peissel. Dangerous Water Creatures. New York: Chelsea House, 1992.

Gilbert, Carter Rowell, and James D. Williams. National Audubon Society Field Guide to Fishes: North America. New York: Knopf, 2002.

Web sites:

"Northern Stargazer." Florida Museum of Natural History. http://www.flmnh.ufl.edu/fish/Gallery/Descript/StarGazerNorth/StarGazeNorth.htm (accessed on October 28, 2004).

"Sand Lance." Fisheries and Oceans Canada.http://www.dfo-mpo.gc.ca/zone/underwater_sous-marin/SandLance/sandlanc_e.htm (accessed on October 28, 2004).