The Atlantic cod has two distinct color phases, grray-green and reddish brown. Its average weight is 10 to 25 lb (4.5–11.3 kg), but specimens weighing up to 200 lb (90 kg) have been recorded. Young Atlantic cod or haddock prepared in strips for cooking is called scrod. Cods feed on mollusks, crabs, starfish, worms, squid, and small fish. Some migrate south in winter to spawn. A large female lays up to five million eggs in midocean, a very small number of which survive. The Pacific cod is found N of Oregon.
The tomcod resembles a young Atlantic cod with long, tapering ventral fins. It rarely exceeds 15 in. (37.5 cm) in length and lives close to shore. There is also a Pacific tomcod. The pollack, also called coalfish or green cod, is a plump olive-green cod found in cool waters of the Atlantic. Pollacks have forked tails and pale lateral lines and grow to 3 ft (90 cm) and 30 lb (13.6 kg).
The haddock is the most important food fish of Atlantic waters; most of the large annual catch is marketed frozen. It is also found in colder European waters. Haddocks are also bottom-feeders but are found in deeper water (up to 100 fathoms). They are smaller than cods, reaching 30 lb (13.6 kg) and a length of 3 ft (90 cm), and have black lateral lines and dark side patches. Finnan haddie is lightly smoked haddock.
Lings and hakes, related to the cod but in several families in the same order, are fishes of commercial importance found in warmer waters. More slender than the cod, they are strong swimmers, preying on crustaceans and small fish. The freshwater, codlike burbot, found deep in northern streams and lakes of North America and Eurasia, is in the same family as the ling. The burbot has a single barbel on its chin.
Cods are classified in the phylum Chordata, subphylum Vertebrata, class Actinopterygii, order Gadiformes, family Gadidae. Lings and burbots are in the family Lotidae; hakes in the families Merluciidae and Phycidae.
See M. Kurlansky,
The Columbia Electronic Encyclopedia, 6th ed. Copyright © 2023, Columbia University Press. All rights reserved.
See more Encyclopedia articles on: Vertebrate Zoology