# Grey Seal (*Halichoerus grypus*)

> The grey seal (Halichoerus grypus) is a large North Atlantic seal named for its long, horse-like muzzle. It swims after fish, squid, and crustaceans along rocky coasts, islands, and ice edges, and a big bull can weigh up to 230 kg. Powerful swimmers, grey seals reach about 24 km/h in the water and can live 25 to 35 years. The IUCN lists the species as Least Concern.

- **Category:** Mammal
- **Conservation status (IUCN):** Least Concern
- **Range:** North Atlantic coasts — Britain, Ireland, Scandinavia, eastern Canada, and New England; half the world population breeds in the UK.
- **Canonical page:** https://globalanimalguide.org/animals/grey-seal/
- **Last reviewed:** 2026-07-16

## Scientific classification

- **Kingdom:** Animalia
- **Phylum:** Chordata
- **Class:** Mammalia
- **Order:** Carnivora
- **Family:** Phocidae
- **Genus:** Halichoerus

## Facts at a glance

| Attribute | Value |
| --- | --- |
| Scientific name | Halichoerus grypus |
| Diet | Carnivore — fish, squid, and crustaceans |
| Habitat | North Atlantic coasts, islands, and ice edges |
| Lifespan | 25–35 years in the wild |
| Weight | 100–230 kg (220–510 lb); males larger |
| Top speed | Up to 24 km/h (15 mph) swimming |
| Conservation status | Least Concern (IUCN) |

## Swimming and diving

Grey seals are strong, agile swimmers, driving themselves through the water with their hind flippers at speeds of up to 24 km/h. They routinely dive to depths of tens of metres and can stay submerged for well over ten minutes while hunting on or near the seabed. A thick layer of blubber keeps them warm in cold Atlantic water and stores energy for the breeding season. On land they are far clumsier, hauling out onto rocks and beaches to rest, moult, and breed.

## Diet and hunting

As carnivores, grey seals take a wide range of fish, along with squid and crustaceans. Sandeels, cod, and other bottom-dwelling fish feature heavily in the diet, and prey choice shifts with the seasons and what is locally abundant. Sensitive whiskers help them detect the movements of fish in dark or murky water. A large adult may eat several kilograms of food each day to fuel its bulk.

## Telling grey seals apart

Grey seals are easily confused with the smaller common (harbour) seal, but a few features set them apart. The grey seal has a long, straight, horse-like muzzle with nostrils that sit almost parallel, whereas the common seal has a shorter, dog-like face and V-shaped nostrils. Grey seals are also noticeably bigger, with bulls far larger than cows. Coat patterns are blotchy rather than neatly spotted.

## Breeding colonies and pups

Grey seals gather in large, noisy colonies to breed, with bulls competing to control stretches of beach and the females on them. Each cow gives birth to a single pup with a fluffy white coat, which she nurses on extremely rich milk. The pup piles on weight rapidly over about three weeks, then is weaned abruptly and left to moult its white fur and take to the sea on its own. Adults may live 25 to 35 years, so a colony contains many long-established animals.

## Where grey seals live

Grey seals are animals of North Atlantic coasts, islands, and ice edges, on both the European and North American sides of the ocean. The coasts of Britain and Ireland are a global stronghold, holding a large share of the world's grey seals, which makes them a familiar sight to UK sea-watchers. They favour remote rocky shores, sandbanks, and offshore islands where they can haul out undisturbed. Individuals may range widely at sea between these haul-out sites.

## Conservation

The grey seal is listed as Least Concern by the IUCN, and numbers in the North Atlantic have generally been stable or increasing. In Britain the species is legally protected, and its populations have grown since the days of heavy hunting. Entanglement in fishing gear, disturbance at breeding beaches, and conflict with fisheries remain the main concerns. Careful monitoring of colonies helps track the health of the wider population.

## Frequently asked questions

### How fast can a grey seal swim?

Grey seals can swim at up to about 24 km/h, propelling themselves with their hind flippers. They are agile in the water and can dive to considerable depths, but they move slowly and awkwardly on land.

### What do grey seals eat?

Grey seals are carnivores that feed on fish, squid, and crustaceans. Sandeels, cod, and other bottom-living fish are important, and their diet shifts with the seasons and local abundance. A large adult eats several kilograms a day.

### How can you tell a grey seal from a common seal?

A grey seal has a long, straight, horse-like muzzle with near-parallel nostrils and is noticeably larger. The common (harbour) seal has a shorter, dog-like face with V-shaped nostrils. Grey seals also have blotchy rather than neatly spotted coats.

### How big do grey seals get?

Grey seals weigh from around 100 kg up to 230 kg, with bulls much larger than cows. They reach roughly 2.3 m in length, making them one of the largest seals in the North Atlantic.

### Where do grey seals live in the UK?

Grey seals breed all around the coasts of Britain and Ireland, favouring remote rocky shores, sandbanks, and offshore islands. The UK holds a large share of the world's grey seals, so they are a common sight for coastal wildlife watchers.

### How long do grey seals live?

Grey seals typically live 25 to 35 years in the wild. Females often live longer than the heavily competing bulls, and long-established colonies contain many older, experienced animals.

## Sources

- [IUCN Red List — Halichoerus grypus.](https://www.iucnredlist.org/search?query=Halichoerus%20grypus&searchType=species)
- [Animal Diversity Web — Halichoerus grypus. University of Michigan Museum of Zoology.](https://animaldiversity.org/accounts/Halichoerus_grypus/)

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Source: Global Animal Guide (https://globalanimalguide.org/animals/grey-seal/). Licensed CC BY-NC 4.0 — free for non-commercial reuse with attribution.