The pinnipeds, or seals, are a group of semi-aquatic mammals with fore and hind flippers, blubber-covered bodies, and carnivorous teeth. Usually fairly cumbersome on land, they become agile and adept in the underwater world, and can be found in both marine and freshwater environments. We will talk in another blog about how the clade evolved, and which animals they are most closely related to, but for now the take-home message is that they are the pinnipeds! The word in latin means fin-footed, and as wide-ranging, higher predators who provide key indicators into the health of the ocean, we have chosen these exciting and diverse mammals to be our namesake.
How many species of seal are there in the world?
The answer is 34! And over the coming months we will be detailing each and every one for you.. a large undertaking! But by focusing on each species in turn, we hope we will all be able to learn something new each week. Sundays are meant for reading, and what better time to take a moment with a cup of tea and educate yourself about life in our beautiful blue ocean? We promise to provide all the facts. So to start us off this Sunday, it’s all about The Harbour Seal (Phoca vitulina).
P. vitulina is one of two seal species that live in the waters of the British Isles. They are a true seal, which means they have no visible ear flaps, and hind flippers that face only backwards, meaning that they are unable to walk on land. Instead these seals are usually seen characteristically dragging or ‘humping’ their bodies forwards. Harbour Seals are also known as Common Seals, and worldwide there are five subspecies.
P. vitulina are a medium sized seal (males up to 2 m long/ 170 kg, females up to 1.7 m/ 130 kg) with a round head and V-shaped nostrils. They are smaller and less gregarious than their UK counterpart cousin, the Grey Seal, and although the two have many differences, it can be easy to confuse them in the field. Look out for our future blog on how to separate the two!
Colouration of P. vitulina can vary across its range, being particularly different in the Pacific compared with the Atlantic Ocean. They can be pale grey through to almost black, and even tan or reddish brown depending on environmental factors and geographic location. Patterns also differ, with some coats all one colour, and others displaying darker speckles, spots, rings or splodges. These patterns are completely unique to the individual seal, in the same way as a human fingerprint, and as such are used by researchers to identify individuals.
In the British Isles, our Harbour seals are the Eastern Atlantic subspecies (P. v. vitulina) and there are estimated to be between 110,000 and 140,000 individuals. Their range stretches across Northern Europe including Iceland, Svalbard and Scandinavia, down to the UK and Ireland, France, Germany, The Netherlands and Poland.