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Natureville / Dumfries
Mammal Here all year · best in calm summer seas

Harbour Porpoise

Phocoena phocoena

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Harbour Porpoise
Photo by Ecomare/Salko de Wolf, CC BY-SA 4.0, via Wikimedia Commons

A small triangular fin rolling once through flat water — no leaping, no show, and gone.

Britain's smallest and commonest cetacean: a compact, dark grey porpoise with a small, blunt, beakless head and a low triangular dorsal fin. Harbour porpoises are seen in the Solway Firth and along the Galloway coast throughout the year. They are easy to miss — they surface briefly and undemonstratively, without the leaping and bow-riding that dolphins go in for.

Porpoises hunt fish using high-frequency echolocation clicks well above human hearing, feeding on herring, sandeel, whiting and other small fish. They usually travel alone or in twos and threes rather than large pods. Calm, flat seas are essential for spotting them — the small fin disappears completely in any chop — and the best chance is on a still morning from a headland or the shore.

Jan — around
Feb — around
Mar — around
Apr — around
May — around
Jun — peak
Jul — peak
Aug — peak
Sep — peak Now
Oct — around
Nov — around
Dec — around
Peak Around
Family
Porpoises (Phocoenidae)
Size
1.4–1.9 m long · Britain's smallest cetacean
UK status
Fully protected; the commonest cetacean in British waters

Photo by Ecomare/Salko de Wolf, CC BY-SA 4.0, via Wikimedia Commons