A Wedell seal puppy lies next to its mother. The puppies have a weight of 25 kg at birth, and 100 kg after six or seven weeks. Grown-ups reach more than 500 kg. The seals bite holes in the thin freezing sea ice, and keep them open continuously with their teeth - even once the ice is as thick as 2 metres. Without these holes they cannot breathe or dive for fish. Wedell seals feed on fish and krill, which they catch at depths of up to 500 metres. During these dives they sometimes stay under water for 75 minutes, and dive as far away as 12 km from their breathing hole in the ice. After a lifetime of around 22 years they have worn off their teeth by the continuous gnawing of the ice around their breathing holes, and thus they usually die early of starvation.