The Harbour Porpoise is one of six species of porpoise. It is one of the smallest marine mammals. As its name implies, it stays close to coastal areas or river estuaries, and as such, is the most familiar porpoise to whale watchers. This porpoise often ventures up rivers, and has been seen hundreds of miles from the sea. The harbour porpoise may be polytypic, with geographically distinct populations representing distinct races: P. p. phocoena in the North Atlantic and West Africa, P. p. relicta in the Black Sea and Sea of Azov, an unnamed population in the northwest Pacific and P. p. vomerina in the northeast Pacific.
Physical Description Edit
The harbour porpoise is a little smaller than the other porpoises, at about 67–85 cm (26–33 in) long at birth, weighing 6.4-10 kg. Adults of both sexes grow to 1.4 m to 1.9 m (4.6-6.2 ft). The females are heavier, with a maximum weight of around 76 kg (167 pounds) compared with the males' 61 kg (134 pounds). The body is robust, and the animal is at its maximum girth just in front of its triangular dorsal fin. The beak is poorly demarcated. The flippers, dorsal fin, tail fin and back are a dark grey. The sides are a slightly speckled, lighter grey. The underside is much whiter, though there are usually grey stripes running along the throat from the underside of the body.
Harbour porpoises prefer temperate and subarctic waters.They inhabit fjords, bays, estuaries and harbours, hence their name.
They feed mostly on small pelagic schooling fish, particularly herring, capelin, and sprat. They will, however, eat squid and crustaceans in certain places. This species tends to feed close to the sea bottom, at least for waters less than 200 m deep. However, when hunting spat, porpoise may stay closer to the surface. When in deeper waters, porpoises may forage for mid-water fish, such as pearlsides.
The social life of harbour porpoises is not well understood. They are generally seen as a solitary species. Most of the time, porpoise are either alone or in groups of no more than five animals.