Despite their name, common seals are in fact less common in the UK than grey seals. They have a dog-like face with large brown eyes, white whiskers and a snub nose. They use their hind flippers to propel themselves forward and small fore flippers to manoeuvre in the water. Their colour varies but their fur is usually speckled grey-brown and may appear silvery when dry.
They have a thick layer of fat, called blubber, which can account for up to 60% of their body weight, compared with a fit human who should only have 15-20% body fat! This layer streamlines them and makes it easier for them to swim and also keeps them warm. They form small, scattered herds and are easily frightened. Although they live in groups, seals are careful to maintain a respectful distance from each other, to avoid confrontation. Seals do not drink seawater. They derive most of their water requirements from their prey.
Breeding Common seals mate in July and August just after they have finished rearing their pups. Then the following year in June or July another litter of pups is born on the sand or on the mud of estuaries or sandbanks exposed at low tide. Pups are able to swim very soon after birth. Females are very attentive to their young and have been known to dive with a pup in their mouth or fore flippers if threatened. The young suckle the mother’s rich milk for about four weeks.
Diet Fish, including cod, herring and mackerel as well as squid, shellfish and crustaceans.
Habitat Prefer sheltered rocky shores and sandy estuaries.
Predators & threats Seals have no natural predators in UK waters and their primary threat is from man.
Status & distribution Large numbers around northern Britain but rare elsewhere; generally increasing. They are found around Scottish waters, including Orkney, Shetland, and the Outer Hebrides as well as a few colonies along the East coast, including Norfolk and the north and south coasts of Ireland.
Did you know? Usually seals’ hearts beat at about 120 beats per minute (compared to 70 beats per minute for humans) but when they dive for periods of up to 30 minutes, they can slow their heart rate down to 40 beats per minute to conserve energy!