About the harbour porpoise
Latin name: Phocoena phocoena
You wouldn’t say it by its name, but the harbour porpoise (Phocoena phocoena) is not a fish at all. On the contrary: it is actually a kind of whale. The smallest species of whale in the world, and it just swims in our own North Sea!
There are seven species of porpoises in the world – in the Dolfinarium you will find the most common porpoise, the harbour porpoise. They are shy animals that often live in murky waters. As a result, little is known about them. The Dolfinarium has been collecting valuable knowledge about the harbour porpoise for many years.
Harbour Porpoises in the wild
In the wild, harbour porpoises are found in the temperate, especially shallow waters of the Northern Hemisphere. It is the most common whale species in the North Sea and Wadden Sea. They eat different kinds of fish, squid and shellfish. They themselves are on the menu of orcas, sharks and gray seals.
Many researchers say that harbour porpoises live solitary — alone — and only come together to mate or when they come to the same food source. But in the wild, harbour porpoises are often seen in groups of four to five individuals. So maybe the researchers are a bit wrong!
The gestation period is about eleven months. So they are pregnant longer than humans! After that, the calf continues to drink milk from the mother for about a year. During this year, the mother also teaches the calf to hunt. Porpoises communicate with each other through soft clicking sounds. Furthermore, little is known about the social life of harbour porpoises.
Physique
Harbour porpoises look very much like dolphins, but are not. Harbour porpoises fall under the toothed whales, of which the harbour porpoise is a separate family. Thanks to their streamlined body, they glide easily through the water.
They have three types of fins: a strong tail fin for speed, pectoral fins for steering and the dorsal fin for stability in the water, much like a boat keel. If you swim in the sea all day, you can still get quite cold. That is why harbour porpoises have a thick layer of blubber that keeps them warm in the water.
They breathe through the blowhole on top of their head, which is in direct communication with the lungs. Did you know that such a blowhole is actually their nostril? They can close this with a lid when they go underwater. And they can’t smell with this nose!
Harbour porpoises have eighty to a hundred pointed teeth, which they use to grab the slippery fish. However, they don’t chew the fish, they swallow it in one go! Do you think you can do that too?
Threats
Due to the wide distribution of the harbor porpoise, it is not endangered in nature (IUCN red list status: not threatened). But they are at risk, for example because they often get caught in fishing nets, causing them to drown or by plastic waste.