Grey Seal: where and when to see them

The grey seal is a large North Atlantic marine mammal with a long muzzle and pronounced differences between males and females. Males are generally larger, darker and heavier-headed, while females often show lighter coats with dark blotches. Scotland and Norway both support colonies on exposed coasts and islands. Seals resting ashore are carrying out essential activities, including digestion, moulting and breeding, rather than waiting to return immediately to the sea.

Size

1.6–2.6 m long

Weight

100–300 kg

Lifespan

25–35 years

Status

Least Concern

Grey seals alternate marine feeding trips with periods resting ashore on rocks, sand or shingle. They may gather densely at suitable haul-outs but retain individual spacing through vocalizations and defensive movements. During breeding, males compete for access to females, and mothers nurse pups on land for a short, intensive period. Young pups initially have white coats. Disturbance can cause sudden movement toward the water, risking injury or separation in crowded groups. Grey seals alternate marine feeding trips with periods resting ashore on rocks, sand or shingle. They may gather densely at suitable haul-outs but retain individual spacing through vocalizations and defensive movements. During breeding, males compete for access to females, and mothers nurse pups on land for a short, intensive period. Young pups initially have white coats. Disturbance can cause sudden movement toward the water, risking injury or separation in crowded groups. Pups are weaned rapidly, typically within three weeks, after which they are left to fend for themselves. Adult seals are known to migrate considerable distances between feeding grounds and breeding colonies.

• Males can weigh substantially more than females.
• Pups are born with a pale, woolly coat that is shed before normal marine life.
• Females nurse pups with exceptionally fat-rich milk.
• Individual coat patterns can help researchers recognize returning animals.

Both destinations offer potential year-round coastal observation, but colony use changes with tides, breeding and moult. Scottish pupping generally occurs in autumn, with regional variation, while Norwegian timing also varies geographically. Summer may offer easier travel without representing the peak breeding period. Both destinations offer potential year-round coastal observation, but colony use changes with tides, breeding and moult. Scottish pupping generally occurs in autumn, with regional variation, while Norwegian timing also varies geographically. Summer may offer easier travel without representing the peak breeding period. The post-breeding moult period in spring and early summer also sees large numbers of seals ashore, offering good viewing opportunities. During autumn, particularly in Scotland, visitors may witness the dramatic breeding season with thousands of seals on land.

They occupy temperate and subarctic coastal waters, using rocky skerries, offshore islands, beaches and sandbanks for resting and breeding. Reliable access between land and sea is important. Exposed colony sites may be visible from distant headlands but inaccessible or closed to visitors. They occupy temperate and subarctic coastal waters, using rocky skerries, offshore islands, beaches and sandbanks for resting and breeding. Reliable access between land and sea is important. Exposed colony sites may be visible from distant headlands but inaccessible or closed to visitors. These seals often use remote, uninhabited islands and islets as primary breeding and resting locations. Their preferred haul-out sites are typically sheltered from strong wave action but remain close to rich foraging areas.

Grey seals eat a varied range of fish, including sandeels, cod-family fishes and flatfish, with cephalopods and other marine prey taken locally. Diet reflects regional availability and individual specialization. Their feeding grounds can lie well beyond the coast where observers see them resting. Grey seals eat a varied range of fish, including sandeels, cod-family fishes and flatfish, with cephalopods and other marine prey taken locally. Diet reflects regional availability and individual specialization. Their feeding grounds can lie well beyond the coast where observers see them resting. They are opportunistic predators, often foraging close to the seabed. Adult seals consume several kilograms of food daily, highlighting their role as apex predators in coastal ecosystems.

Common name

Grey Seal

Scientific name

Halichoerus grypus

Animal group

Mammals

Size

1.6–2.6 m long

Weight

100–300 kg

Lifespan

25–35 years

Status

Least Concern

Identification

Compared with the harbour seal, it has a longer, straighter muzzle and more widely separated nostrils rather than a compact, catlike face with a clear V-shaped nostril pattern. Compared with the harbour seal, it has a longer, straighter muzzle and more widely separated nostrils rather than a compact, catlike face with a clear V-shaped nostril pattern. Adult males, known as bulls, are generally larger and often have darker pelage with fewer spots than females. Grey seals also possess a distinctive Roman nose profile, particularly noticeable in older males.