Aside from the brief attachment formed by a mother with young, or the even briefer union between a mating pair, the hooded seal is relatively antisocial. Indeed, it is only during the moulting and breeding seasons that this solitary species aggregates in loose groups. Lasting only two to three weeks, the breeding season takes place at the end of March, with the females hauling out on ice floes to give birth (2) (3). The pups are born in an exceptionally advanced developmental state, and are weaned after just four days, the shortest lactation period known for any mammal (3) (4) (5). During this time, the mother and pup are usually attended to by an amorous male vying to take advantage of the female's imminent receptivity. In order to assume the position of 'attendant', the males typically compete amongst each other, with the posturing of nasal appendages often being the prelude to more bloody transactions (3). At the end of the brief lactation period, the male and female return to the water and immediately mate, following which the male may go in search of another available female, while the female returns to the open sea to forage. Owing to a four month period of delayed implantation, it will be another year before the female gives birth again. Meanwhile, the abandoned pup remains alone on the ice for several days, or possibly weeks, where it survives entirely on its stored fat reserves (2) (3). Eventually, it will make its first forays into the water, where it must teach itself to swim, dive and forage. As an adult, it will forage for deepwater fish and squid, diving down to depths of over 1,000 metres for over an hour at a time, but while the pup's aquatic skills are developing, krill and other invertebrates must form the bulk of its diet (3) (5). Little is known about the movements of juveniles during the first few years, but upon reaching sexual maturity (three years for females and four, or more, for males), the young adults join the annual migration with the pack ice (3) (4).