Sei whale  (Balaenoptera borealis)

Few details of the natural history of this whale are known. They tend to occur in groups of between two and five individuals (5), but larger groups may form in areas where food is very abundant (5). Capable of travelling at great speed, this species is believed to migrate into warmer waters at lower latitudes during the winter months (8). Little is known of communication in this species, but individuals are known to make many low frequency sounds (7).