Grey Seal (Halichoerus grypus)

Grey Seal

UK History

In the early 20th century the UK grey seal population was thought to number just 500 and consequently they were the first mammals to be granted legal protection by the Grey Seals Protection Act of 1914. Culls in the 1960s and 1970s were opposed and halted by public outcry in Britain and emerging international environmentalism. Currently protected by the Conservation of Seals Act (1970) during a closed season from 1st September to 31st December.

UK Status

It is estimated that the total UK population is approx. 120,000, with around 90% of these in Scottish waters.

Global Status

There are three distinct populations of grey seals -
the western Atlantic population (> 150,000); the eastern Atlantic population (130 - 140,000) and the Baltic Sea population (7,500).

Biology

Breeding colonies gather at traditional ‘rookeries’ around the UK coast from late September to December. Grey seal pups weigh about 14kg at birth. They remain on land where they suckle from their mother for 18-21 days. The largest males, usually more than 10 years old, compete for a position within groups of breeding females. The pups stay in the rookery surviving on their blubber reserves until after the final moult, then go to sea. Females may live for 35 years, but males seldom survive to more than 25 years old. Grey seals feed on a wide variety of fish, crustaceans and cephalopods.

Issues with humans

In the past, grey seals have been killed for their skins, meat and oil in the UK, Iceland, Canada and the Baltic. Bounties and cull programs have been initiated by different countries over the last century. Today, grey seals are rarely used as a resource but are considered a pest in certain areas.

A dramatic increase in the UK population has brought grey seals into conflict with the fishing industry on a number of issues. Seals try to take salmon from fish farms; they damage fishing gear; compete with commercial fisheries and harbour fish parasites.

Recent research indicates that grey seals eat large quantities of sand eels, which are caught for use in fish meal but not for human consumption. Salmon does not appear to be an important part of the seal's diet, although other commercially important fish like cod are taken.

Future Outlook

The UK grey seal population is still increasing and this is likely to bring them into further conflict with the fishing industry. Although protected during the closed season, seals can be legally shot if they are damaging fish nets, traps or catch. UK fishermen and fish farmers do not need to report the shooting of seals under the "Fisheries Defence Clause" of the Conservation of Seals Act and therefore the scale of such killing is uncertain. Illegal shooting remains a threat to seal populations throughout their range.

Grey seals are sensitive to disturbance by people and dogs, particularly when lactating. They are also susceptible to oil and chemical pollution (most notably the Baltic Sea population) and often become tangled up in fishing nets, which may be fatal.

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