Risso’s dolphin are much larger than harbour porpoise, between 2.8-4.1m long. They have a tall dorsal fin, which is sometimes confused with that of the Orca. They are the most frequently seen cetacean in Orkney waters, sometimes seen in large pods of over 30 animals. Their head is square-shaped and lacks a characteristic ‘dolphin-shaped’ beak. Harbour porpoises are possibly harder to spot as they are smaller (adults are between 1.2-1.9m in length); often don’t approach boats and are more often seen individually rather than in a pod. Look out for a dorsal fin, which is low and triangular and if you’re lucky enough to be close to the animal, listen out for a distinct puffing sound as it breathes. This gives the porpoise the nickname of ‘puffing pig’. Any sightings can be logged with the Orkney Marine Mammal Research Initiative here.
Cetaceans (Papa Westray)
Two species of cetacean that you might see in this stretch of water are Risso’s dolphin and Harbour porpoise. Both are seen most in late summer, and early autumn.