Grey seal aggression (Halichoerus grypus). Female grey seals fighting in shallow water. The grey seal can be aggressive at times especially during the breeding season. A male seal may fight for mating rights over the female and a female seal may fight to protect its territory and young. The female grey seal gives birth after a gestation period of just under a year. A pup is nursed for up to two months before becoming independent. The grey seal lives in large groups in coastal waters in the North Atlantic Ocean. It feeds almost exclusively on fish. Photographed in December, on a sandbank, near the Humber estuary, in Lincolnshire, UK.