Two species of True seal exist around the UK seaboard, the Common seal, Phoca vitulina , and the Grey seal, Halichoerus grypus . Occasional vagrants visit our shores including Walrus, Ringed seal, Harp seal, Hooded seal and Bearded seal, but so rarely as to be discounted.
Statistics are like the pup in the pic.
It is likely that there are around 200,000 Grey seals and 30,000 Commons off the UK shores in 1998. Grey seal nostrils appear as nearly parallel slits while those of the common seal form a V shape. The long Roman nose of the male Grey is unlikely to be confused with the short pug nose of the Common though the females of both species are more difficult to distinguish. By mid-October, several hundred seals will have given birth around the Treshnish Isles, creating the impression of a moving live beach in some areas. Common seals are usually brown to grey in colour and are frequently better camouflaged in their chosen environment - usually closer inshore in more sheltered waters than their larger relatives.