• Name: Atlantic grey seal | Halichoerus grypus
  • Size: Bulls (males) average about 2.5 metres (7.5 feet) in length, Cows (females) average about 1.8 metres (5.9 feet) in length 
  • Life span: Bulls (males) can live up to 30 years, Cows (females) can live up to 40 years in the wild 
  • Diet: Predominantly fish (i.e. Sand eels, Pollock, Flatfish), but will eat Crustaceans (i.e. Crab & Lobster), Squid Octopus and sometime Seabirds.
  • Reproduction: Females (of breeding age, approximately 5 years) give birth to a single Pup between August & December
  • When to see: All year round (January to December)
  • Where to see: Sheltered bays and rocky outcrops i.e. Pelistry, St Mary's | Great Bay, St Martins | Great Par, Bryher in Scilly.  Alternatively, head out with a WiSe accredited boating provider to the Eastern Isles or Western Rocks (Help us with monitoring our Seal populations by sending any photos you take to Cornwall Seal Group Research Trust!) 
  • Conservation status: ICUN Redlist | Least Concern.
  • Population Trend: Increasing
  • Threats:  Human activity (i.e. fishing and disturbance), pollution, climate change (changes in weather patterns, changing sea temperatures). 
  • Fun Fact: Atlantic grey seals are protected in Britain under the Conservation of Seals Act 1970.  Despite their conservation status and increasing population trends they are actually a globally rare species; there are more Red Squirrels i the UK than there are Atlantic grey seals!

Description: Halichoerus grypus literally translates rather unceremoniously to “Hook-nosed sea-pig”; these “sea-pigs” are more commonly known to you and I as the Atlantic grey seal.

Atlantic grey seals are the largest carnivore living in Britain and are among the rarest seals in the world; with the UK Grey seal colonies representing around 40% of the total world population of Grey seals and 95% of the European population!

The grey seal can be distinguished from the Common seal by its larger size and longer head with a sloping 'roman nose' profile. Looking straight on, their nostrils are parallel, rather than v-shaped as with Common seals.

Grey seal pups they are born with white fur, which they start to shed at around two to three weeks of age to reveal their grey adult coats (on occasion melanistic or pure black Seals are revealed at this point).  Grey seals fur patterns and colour varies hugely, including grey, cream, brown, black markings; their fur patterns are unique (much like a finger print) and can be used to identify individuals.

Seals sleep both on land and in the water; tending to sleep on land (hauled out) when they are searching for warmth, to escape from rough seas or when they have pups.  When Seals sleep in the water, they sleep in a position known as "bottling" (floating vertically in the water column with their noses above the surface); sleeping with only half their brain, to remain aware of their surroundings and potential dangers, they can also open and close their nostrils to prevent water from entering and drowning.

Between September and January pups are regularly spotted on the beaches of our inhabited Islands; they generally come ashore for a rest or sometimes because they are unwell.

When pups are found on our beaches if they look healthy they are left to their own devices and monitored; if they are looking unwell then our local vet, Heike, and a number of on-island Marine Mammal Medic volunteers are trained to respond appropriately and will sometimes take them into care before getting them flown to the Seal Sanctuary at Gweek for rehabilitation.

If you see a Seal, of any age, hauled out resting please #RespectTheNap, give them a wide birth, and #DoNotDisturb.

Want to know more?  Find out more about our work with Cornwall Seal Group Research Trust, surveying, monitoring and Seal ID


Do remember that we rely on donations to continue our work.  If you have searched, found and learned about Scilly's wildlife on our website, please Support Us and give what you can.  Thank you 💚

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With thanks to BareFoot Photographer for the hauled out Seals image


Here is a short film produced by Natural England highlighting the importance of Atlantic Grey Seals

Whether you live in Scilly or are just visiting make sure you know how to "Watch Wildlife Safely"; for it's benefit and yours!  Disturbance of our Marine Wildlife can have devastating consequences, so before you head out on the water take a look at our handy leaflet which gives loads of advice on how to watch wildlife safely - click on the image below