The grey seal: the tough inhabitants of the Wadden Sea
150 - 300 kg
2 - 2,5 meter
30 km/h
Swimming speed
30 minutes
Holding their breath
25- 35 years

About the grey seal

In the Dolfinarium you will meet two types of seals: the common seal and the grey seal. The grey seal (Halichoerus grypus) can be recognized by – you guessed it – its grey color. But also the shape of the head, which looks a bit like a cone. That is why grey seals are also called cone seals.

Rob, seal, sea lion?

What’s up? It’s actually quite simple: rob is just another name for seal. And no, that doesn’t mean our grey seals are all called Rob! Seals and sea lions are both called “pinnipeds,” meaning they are mammals with fins instead of legs. But the fins of seals are not the same as those of sea lions. If you would see them walking side by side, you immediately see the difference: the sea lion can ‘walk’ on its front fins, while seals are more bumpy.

Are you lucky enough to spot an animal up close and unsure whether it is a sea lion or seal? Then find the ears. See those on the outside? Then you face a sea lion. No ears in sight? Then it’s a seal!

Grey seals in the wild

In the wild, grey seals occur around the northern coasts of the Atlantic Ocean, and also in the North Sea and Wadden Sea. They live on sandbanks, beaches and rocky coastal areas. As cute as they look, they are true predators, preying on various types of fish, squid, shellfish, and crustaceans. They themselves are eaten by orcas and large shark species.

Grey seals are solitary, meaning they like to be alone. But at resting places or during the mating season they gather in large groups. They can sometimes be quite aggressive towards each other!

During the mating season, female seals mate with several males. The young are born after a gestation period of 11 months – so they are almost a year pregnant. And just like with ‘regular’ dogs, we call them puppies too! Grey seal pups weigh about eighteen kilograms and have a white, fluffy coat for the first two to four weeks.

Young grey seals are often born in areas that are submerged at high tide, so they should be able to swim almost immediately. Grey seal pups only spend a short time with their mother: after drinking milk from the mother for about eighteen days, the young are already on their own.


Seals move on land by bumping or rolling on their stomachs. They have sharp claws on their small front fins, which they use for scratching, pulling large prey apart and for extra grip on ice floes or slippery rocks. They also have very sensitive whiskers that allow them to sense vibrations in the water that their prey leaves behind. That way they can even hunt in murky water! So no fish is safe from them.

The grey seal is a lot bigger than the common seal, which also lives in the Dolfinarium. You can tell by the coat color whether it is a male or a female: a male is dark in color with light spots, and with females it is exactly the other way around!

Grey seals have 34 sharp teeth and molars that they use to catch their slippery prey. But they don’t chew with that: they gobble their prey down in one go! That is quite different from how we humans eat – better give us a knife and fork…


Fortunately, the grey seal is not endangered in the wild (IUCN red list status: not threatened). However, many seals, like other sea creatures, are at risk from various factors such as plastic waste, climate change and commercial fishing.

In the Dolfinarium you will find the grey seal here, where you can see them chilling on a sandbank, bumping on the beach and swimming through the water. And during the educational presentations, the seal keeper shows how his animal friends live, what they eat and what the Dolfinarium does to conserve their species in the wild.

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Volgende show: 13:30 uur - Dolfijnenshow
On this moment: Actueel weerbeeld als pictogram 22 °C