Skip to main content
Aquarium Home

Wolf Eel

Anarrhichthys ocellatus

Wolf eels may look eel-like in appearance but they have a key difference. Wolf eels have large pectoral fins behind their heads like fish, as opposed to true eels that have very small fins or lack fins entirely. Wolf eels love to feed on crustaceans, urchins, and juvenile fish. They can be found in stone covered coastal areas and rocky reefs. They rarely move from their homes, and are known to be gentle and slow moving. Male and female wolf eels form strong bond pairs during mating season. A female wolf eel can lay up to 10,000 eggs at a time.

Aquarium Placeholder Image Blue with Logo

SPECIES IN DETAIL

Wolf Eel

Anarrhichthys ocellatus

CONSERVATION STATUS: Safe for Now - Protected

CLIMATE CHANGE: Uncertain

At the Aquarium

Northern Pacific Preview

Geographic Distribution

They are found in the North Pacific from the southeastern Bering Sea and eastern Aleutian Islands to Southern California.

Habitat

The wolf eel can be found along the stony bottoms of the ocean, rocky reefs, and kelp forests. Their range of depth spans from 316 meters to 416 meters (1,036 feet—1,365 feet).

Size

Length: They grow up to 2.4 meters (7.9 feet). Weight: They weigh up to 18.4 kilograms (40.6 pounds).

Diet

In the wild, wolf eels eat crustaceans, echinoderms (primarily urchins), invertebrates (mollusks) and juvenile rockfish. At the Aquarium, they are fed crustaceans, shellfish, fish, and squid.

Reproduction

Male and female wolf eels pair bond throughout the breeding season. When a female wolf eel is four years old, she can lay up to 10,000 eggs. The female wolf eel uses her body to shape the eggs into a sphere and coils around them. The male will then coil himself around the female to further protect the offspring. Spawning occurs in nesting holes where eggs are incubated by the parents. The parents massage the water over the eggs to circulate oxygen. After 3—4.5 months, the eggs will hatch and the juvenile larvae enter a free swimming phase. Once the larvae mature, they will search the sea bottom for food, shelter, and a mate.

Behavior

The juvenile wolf eels free swim after hatching. Once they mature, the wolf eels will search the sea bottom for a rocky structure or crevice to hide in. When a suitable habitat is found, the eel will become sedentary and protective of its space.

Adaptation

Wolf eels have a compressed elongated body. Wolf eels look similar to true eels, however, they have pectoral fins behind their head while most true eels have small fins or completely lack fins. They also have large blunt heads with large protruding caniform (like the human canine) teeth that are 0.015 meters (0.59 inches) long. Their large teeth are perfect for crushing hard shells.

Longevity

Their life span in the wild is unknown (one individual observed in the wild lived up to twenty years), and their life span in aquaria is about twenty-five years.

Conservation

The species is occasionally fished. The known fisheries are currently not known to have a negative effect on the global population.

Special Notes

A juvenile of this species was found to have migrated 593 kilometers (368 miles) between British Columbia and Washington.

Harbor seals have been observed preying upon adult wolf eels, which may be the longest prey animal reported for the harbor seal.

SPECIES IN DETAIL | Print full entry

Wolf Eel

Anarrhichthys ocellatus

CONSERVATION STATUS: Safe for Now - Protected

CLIMATE CHANGE: Uncertain

They are found in the North Pacific from the southeastern Bering Sea and eastern Aleutian Islands to Southern California.

The wolf eel can be found along the stony bottoms of the ocean, rocky reefs, and kelp forests. Their range of depth spans from 316 meters to 416 meters (1,036 feet—1,365 feet).

Length: They grow up to 2.4 meters (7.9 feet). Weight: They weigh up to 18.4 kilograms (40.6 pounds).

In the wild, wolf eels eat crustaceans, echinoderms (primarily urchins), invertebrates (mollusks) and juvenile rockfish. At the Aquarium, they are fed crustaceans, shellfish, fish, and squid.

Male and female wolf eels pair bond throughout the breeding season. When a female wolf eel is four years old, she can lay up to 10,000 eggs. The female wolf eel uses her body to shape the eggs into a sphere and coils around them. The male will then coil himself around the female to further protect the offspring. Spawning occurs in nesting holes where eggs are incubated by the parents. The parents massage the water over the eggs to circulate oxygen. After 3—4.5 months, the eggs will hatch and the juvenile larvae enter a free swimming phase. Once the larvae mature, they will search the sea bottom for food, shelter, and a mate.

The juvenile wolf eels free swim after hatching. Once they mature, the wolf eels will search the sea bottom for a rocky structure or crevice to hide in. When a suitable habitat is found, the eel will become sedentary and protective of its space.

Wolf eels have a compressed elongated body. Wolf eels look similar to true eels, however, they have pectoral fins behind their head while most true eels have small fins or completely lack fins. They also have large blunt heads with large protruding caniform (like the human canine) teeth that are 0.015 meters (0.59 inches) long. Their large teeth are perfect for crushing hard shells.

Their life span in the wild is unknown (one individual observed in the wild lived up to twenty years), and their life span in aquaria is about twenty-five years.

The species is occasionally fished. The known fisheries are currently not known to have a negative effect on the global population.

A juvenile of this species was found to have migrated 593 kilometers (368 miles) between British Columbia and Washington.

Harbor seals have been observed preying upon adult wolf eels, which may be the longest prey animal reported for the harbor seal.