Harbour Porpoise
Common Name:Harbour Porpoise
Latin Name:Phocoena phocoena
Other Names:Common porpoise, Puffing pig
Primary Classification:Odontocete (Toothed whale, dolphin or porpoise)
Sub Classification:Phocoenidae
Description:
Harbour porpoises are small compared to other species of porpoise. They have a rounded head which slopes down to the mouth, and they do not have beaks. They have a dark grey/ blue back, and a white or light grey coloured belly. Harbour porpoises have black lips, a black chin, and a mouth that curves up slightly which makes them look like they are smiling! Their dorsal fins have blunt tips and are just past the centre of their backs. Young harbour porpoises are dull in colour compared to their parents, and in the first few hours after they are born they have birth lines, which look like large pale folds in their skin.
Field ID:
Robust body, Small size, Small head, Flat forehead, No prominent beak, small dark and slightly rounded flippers, non-descript colouring, Dark upper-side (top), Lighter under-side (belly), Triangular dorsal fin with blunt tip, Slow swimmer, Difficult to approach, Normally in small groups or alone
Length (metres):
When they are born, harbour porpoises are 67 to 85cm (26 -34in) long. When they are fully grown, they measure between 1.4 and 1.9 metres (4ft 9in - 6ft 3in).
Weight:
At birth, harbour porpoises weigh 5kg (11lb). They weigh between 55 kg and 65kg (125 - 145lb) when they are adults.
Diet:
Fish, and occasionally squid, krill or other crustaceans.
Behaviour:
Although harbour porpoises live close to land, they are very shy creatures and mostly stay below the surface of the water. However, they are occasionally spotted when resting at the surface, and also when they flash their white bellies as they roll. They swim slowly, and usually alone, or in small groups. They can dive underwater for as long as six minutes, before they come back up for breath! The blow of the harbour porpoise is difficult to see, but can be easily heard by the puffing sound that it makes, which is rather like a sneeze. They usually stay underwater, and keep away from boats.