The Grey Seal (Halichoerus grypus)
 Identification
The grey seal is the larger of the two species of seal found regularly around our coastline. In fact, it is the largest resident mammal in the UK and Ireland.
It is recognised by its elongated muzzle and parallel nostrils.
Males tend to be dark grey or brown with a few pale patches. The underside is paler grey. Female colour is extremely variable with shades of light and dark grey, brown and silver occurring on the back. The underside is pale grey-cream with scattered darker blotches. These blotches are larger than the spots on the common seal. Pups are born covered in white fluffy fur (lauugo) but shed it after two to three weeks, revealing their first adult coat.
 Size
Adult males are substantially larger than females measuring about 2.5m and weighing up to 300kg (as heavy as a horse!).
Adult females measure about 1.8m and weigh about 175kg.
Pups weigh about 15kg at birth.
Distribution
There are three distinct groups of grey seal in the world. All three occur in temperate and arctic waters. The three groups occur in the Baltic, the Eastern Atlantic and the Western Atlantic.
Population
| World population |
250,000 |
|
| UK population |
over 100,000 |
(They are most abundant around Scotland) |
| Irish population |
3,000 |
|
Habitat
Grey seals favour exposed rocky coasts, islands and caves.
Breeding
Grey seals are born between September and December. At birth, they weigh about 15kg and are covered in white fluffy fur (lanugo). This fur is easily waterlogged so the majority of pups stay ashore for the duration of lactation. The mother comes ashore to suckle the pup and then returns to the water. Suckling varies between mother-pup pairs but the average duration is about 10 minutes, every 5-6 hours (depends on location /tides). When in the water the mother normally stays close to shore and does not feed during the lactation period. The pup, on the other hand, rapidly gains weight feeding on milk, which contains about 60% fat. After 2-3 weeks, the pup weighs 45kg, three times its birth weight. The pup is weaned but remains ashore living off its fat reserves until it looses its white fur.
Mating occurs soon after the pups are weaned.
Males reach sexual maturity at 5-6 years old, females at 3-5 years.
 Lifespan
Males live up to 25 years old, females up to 35 years old.
Conservation
The grey seal was the first mammal in Britain to have its own Act of Parliament, the Grey Seal Protection Act of 1914. Grey seals can only be culled under licence.
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