Eelpouts and Relatives: Zoarcoidei

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EELPOUTS AND RELATIVES: Zoarcoidei

WOLF-EEL (Anarrhichthys ocellatus): SPECIES ACCOUNTS
_OCEAN POUT (Zoarces americanus): SPECIES ACCOUNTS

PHYSICAL CHARACTERISTICS

Most eelpouts and their relatives are shaped like eels. They usually are less than 16 inches (40 centimeters) long, but some reach a length of 24 inches (60 centimeters). The wolf-eel is the largest fish in this group, reaching a length of 80 inches (2 meters). Eelpouts are usually gray, brown, black, or purple and have spots of various colors.

GEOGRAPHIC RANGE

Eelpouts and their relatives live all over the world from the Arctic to Antarctica.

HABITAT

Some eelpouts and their relatives live above the high tide line in rock pools, burrowing in sand or gravel beaches. Some live in rocky reefs in seaweed and keep well hidden by day. Other species live as far as 2 miles (4,000 meters) deep in the ocean.

DIET

Most eelpouts and their relatives hunt for worms, clams, sea urchins, smaller fishes, sea snails, crabs, hermit crabs, starfish, jellyfishes, and plankton, which is microscopic plants and animals drifting in water. Some eat only algae (AL-jee), which are plantlike growths that live in water and have no true roots, stems, or leaves.

BEHAVIOR AND REPRODUCTION

Most eelpouts and their relatives live alone and hide but may gather for a short time in shelters or around food sources. During the winter in colder regions species that live near the shore may travel into deeper water to avoid freezing. Scientists know little about the reproduction of eelpouts and their relatives. In some species eggs are fertilized (FUR-teh-lyzed), or joined to sperm to start development, inside the female and then are laid. In other species, eggs are fertilized as they are laid in clusters. Most of the nearshore eelpouts and their relatives spawn during the day, when they can see one another for courting. Some eelpout relatives guard their nests.

EELPOUTS, THEIR RELATIVES, AND PEOPLE

Except for wolf-eels, eelpouts and their relatives are not fished for food or fun.

CONSERVATION STATUS

Eelpouts and their relatives are not threatened or endangered.

WOLF-EEL (Anarrhichthys ocellatus): SPECIES ACCOUNTS

Physical characteristics: Wolf-eels have a long, snake-like body and reach a length of about 6 feet (2 meters). The background color is blue, greenish brown, or grayish brown. The body and head are covered with white-lined black spots. The scales are small and rounded and embedded in the skin. The dorsal (DOOR-suhl) and anal (AY-nuhl) fins are very long and low; the pectoral fins, large and fanlike. There are no pelvic fins. The dorsal fin is the one along the midline of the back. The anal fin is the one along the midline of the belly. The pectoral (PECKter-uhl) fins correspond to the front legs of four-footed animals. The pelvic fins correspond to the rear legs of four-footed animals. The mouth is large and has big lips. The front teeth are like dog or wolf teeth. The back teeth are molars like those of people.


Geographic range: Wolf-eels live along the coast of North America from Alaska to California.


Habitat: Wolf-eels live on deep rocky reefs in caves or crevices. The young live in open water.


Diet: Wolf-eels eat crabs, clams, mussels, sea urchins, sand dollars, and snails. The young eat plankton.


Behavior and reproduction: Wolf-eels hide and live alone or with a lifelong mate in a den. They hunt at dusk and dawn but also feed during the day. Wolf-eels grab their prey, or animal hunted and killed for food, with their large front teeth and crush it with their molars.

Wolf-eels form pairs when they are about four years old and first lay eggs when they are about seven years old. In courtship the male repeatedly bumps the female's belly. When the female is ready, the male coils around her. The eggs are fertilized as they are laid in clumps, and the female gathers the clumps up into a ball and wraps around them, turning them once in a while so that they all get enough oxygen. Both parents guard the nest, and one always stays with the nest while the other looks for food. Young wolf-eels swim freely for up to two years then settle on the bottom until they begin their den life.


Wolf-eels and people: Wolf-eel tastes good and is caught by scuba divers and fishermen. Wolf-eels have been known to snap at fishermen and can inflict serious bites on scuba divers who spear them.


Conservation status: Wolf-eels are not threatened or endangered. ∎

OCEAN POUT (Zoarces americanus): SPECIES ACCOUNTS

Physical characteristics: Ocean pouts have a body that is eel-like but rather stout. The background color usually is muddy yellow tinged with brown but becomes darker with age. The belly is yellow or olive green. There are brown splotches on the sides. The dorsal and anal fins are long and low. The pectoral fins large and fanlike. Some ocean pouts have green teeth because they eat sea urchins. Ocean pout scales are tiny and round and do not overlap.


Geographic range: Ocean pouts live along the coast of North America from Labrador, Canada, to Virginia, United States.

Habitat: Adult ocean pouts live off shore on sandy or muddy bottoms. The young may come closer to shore and live among seaweed and rocks.


Diet: Ocean pouts graze on the sea floor for crabs, hermit crabs, sea urchins, worms, clams, sea snails, and sea stars.


Behavior and reproduction: Scientists know little about the behavior of ocean pouts. These fish probably live alone and gather only for spawning. Spawning males approach females and roll on their sides or even upside down under the female. The eggs are fertilized inside the female and then laid in rocky areas. After laying her egg mass the female fans the eggs with her fins and wipes her skin over the eggs for about thirty minutes, coating them with protective mucus. She then wraps herself tightly around the mass, helping it stick together in a ball.


Ocean pouts and people: Ocean pouts once were fished for food.


Conservation status: Ocean pouts are not threatened or endangered. ∎

FOR MORE INFORMATION

Books:

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

Web sites:

Kruse, Katrina. "Wolf-eel Anarrhichthys ocellatus." North American Native Fishes Association. http://www.nanfa.org/fif/wolfeel.shtml (accessed on February 11, 2005).

"The Ocean Pouts and Wolf Eels: Family Zoarcidae." Gulf of Main Research Institute, Fishes of the Gulf of Maine.http://octopus.gma.org/fogm/Zoarcidae.htm (accessed on October 28, 2004).