They grow to about 30 cm long, and are favorite food of narwhals and other arctic whales.

[4] Another Arctic gadid, the East Siberian cod (Arctogadus borisovi), was until recently considered the closest relative of A. glacialis.

[5] Arctic cod have been cited to grow up to 32.5 cm (12.8 in) in total length.

The fish lives close to the sea floor at depths of 15 to 40 m, but it sometimes enters estuaries, and may also be found under pack ice.

A. glacialis in an ice-free area off northeastern Greenland were found to feed almost exclusively on pelagic prey (primarily copepods, amphipods, and mysids).