Found on continental and insular shelves and upper slopes, ranging from shallow inshore waters and the intertidal to 200 m, occasionally down to 579 m (Ref. 244). Occasionally found in freshwater. It is doubtful that this species can live in fresh water for an extended period of time (Ref. 244). Feeds on large crustaceans, mainly crabs, but also heavily on lobsters (Homarus) (Ref. 244). Probably non-territorial. Off the Atlantic coast of the USA, this species is migratory (Ref. 244). Viviparous (with a yolk-sac placenta), with 4 to 20 young in a litter. Longevity given as 7 years (Ref. 775) but appears too low. Utilized fresh, dried-salted, and smoked (Ref. 9987).