The female is lighter in colour, with dark spots on a grey, tan or yellowish background. In the water, grey seals tend to be solitary or in small groups, but on land they are gregarious and can be found hauled out with harbour seals in areas where the two species coexist. Each population breeds at a different time and variation within the populations also exist. Pups weigh 11-20 kg at birth and are weaned at about 3 weeks of age. At this time, mating occurs between waiting males and receptive females.
Grey seals feed on a wide variety of fish, crustaceans and cephalopods.
The diet varies with location, season and prey availability. Fasting occurs during the breeding and moulting seasons. Status The Northwest Atlantic population is estimated at 85,000-110,000 animals. The Baltic grey seal is thought to number between 2,000 and 3,000 animals. I n the past, grey seals have been killed for their skins, meat and oil in the UK, Iceland, Canada and the Baltic.