eel

eel, common name for any fish of the 10 families constituting the order Anguilliformes, and characterized by a long snakelike body covered with minute scales embedded in the skin. Eels lack the hind pair of fins, adapting them for wriggling in the mud and through the crevices of reefs and rocky shores. Most species are marine; the largest and most diverse group are the morays, family Muraenidae, sharp-toothed and vicious. The common freshwater eel, Anguilla rostrata, of the family Anguillidae, is found in the Atlantic coastal regions of Europe, in the Mediterranean area, and in North America E of the Rockies. Several other freshwater species are native to Asia. The mature European eel migrates 3,000 to 4,000 mi (4,828–6,437 km) to its spawning ground in the deep sea SW of Bermuda, a journey lasting several months. There it reproduces and then dies. The young hatch as transparent ribbonlike larvae that drift north and east on ocean currents for three years before entering a river; they then develop into elvers, tiny versions of the adult eel. The American eel follows the same pattern, except that the young require only one year to return to freshwater. Once there, the developing elvers feed voraciously on dead and living animals, even traveling over short stretches of land in search of frogs and lizards. They hunt at night and rest by day. The male, which attains a length of 2 ft (61 cm), remains at the river's mouth, while the female (4 ft/122 cm) swims upstream, staying there from 5 to 20 years. When the eels are sexually mature their enormous appetite wanes, and they do not eat during migration to the spawning ground. The oily flesh is regarded by some as a delicacy; the skin was formerly used as leather. Eels are classified in the phylum Chordata, subphylum Vertebrata, class Osteichthyes, order Anguilliformes.

Bibliography

See R. Schweld, Consider the Eel (2002).

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eel

Any of more than 500 fish species (order Anguilliformes) that are slender, elongated, and usually scaleless, with long dorsal and anal fins that are continuous around the tail tip. Eels are found in all seas, from coastal regions to the mid-depths. Freshwater eels are active, predaceous fish with small embedded scales; they grow to maturity in freshwater and return to the sea, where they spawn and die. The transparent young drift to the coast and make their way upstream. Freshwater eels, considered valuable food fish, include species ranging from 4 in. (10 cm) to about 11.5 ft (3.5 m) long. See also moray.

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eel

1. any teleost fish of the order Apodes (or Anguilliformes), such as the European freshwater species Anguilla anguilla, having a long snakelike body, a smooth slimy skin, and reduced fins

2. any of various other animals with a long body and smooth skin, such as the mud eel and the electric eel

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eel [ēl]

(vertebrate zoology)

The common name for a number of unrelated fishes included in the orders Anguilliformes and Cypriniformes; all have an elongate, serpentine body.