Breeding

Breeding takes place between January and March. Large herds of bulls, cows and calves gather together and the bulls fight for the cows. Those with the longest tusks are those who get to mate with the cows, and each victorious male will mate with several.

Mating takes place in the water, and a single calf is born about 15 months after mating, often as the herds are heading back north after the winter. The female hauls out onto an ice floe to give birth to her calf, which measures 125cm at birth. The calf first travels by hanging onto its mother's neck, but it is quickly taught to swim and is quite a capable swimmer by two weeks of age. The calf feeds on its mother's rich milk for at least 18 months, but begins to eat solid food after six months and after a year will usually have tripled in weight. The calf separates from its mother after about two years, and attaches itself to a herd of young walruses.