skip to main content

Related links

Harbour porpoise in Scotland

Harbour porpoises are the smallest cetaceans found in Scottish waters. They are just 1.4 -1.8 metres long, and weigh up to 90 kg. They have small, rounded bodies and short heads, without the typical beaks of dolphins. Although closely related to dolphins, there are a number of differences between them. To anyone watching from the surface, the easiest way to distinguish them is to look at the shape of the dorsal fin on the animal's back. All the dolphins found in Scottish waters have tall, sickle-shaped dorsal fins, whereas the fin of the harbour porpoise is small and triangular in shape.

They are typically found in shallow, coastal waters with depths of less than about 100 metres. Although they are found throughout Scottish waters, they are more common along the west coast and around the Western and Northern Isles, particularly in summer. If you are patient and watch carefully from a headland in these areas, there is a good chance you may see a harbour porpoise, although, in rough weather, it can be difficult to pick out their small dorsal fins in choppy waters.

Harbour porpoises feed on a wide range of fish, including herring, whiting and sandeels. They usually travel alone or in small groups. However, if they find an abundant source of food, they will often come together to feed in groups of 100 animals or more, creating a spectacular sight. They are much less likely to display than other cetaceans. Most typically, you will get only a glimpse of a porpoise passing by quickly, coming occasionally to the surface to breathe, as it moves on to other feeding areas.

Harbour porpoise David Ainsley