Phocoena phocoena - Common porpoise:

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Summary Information
Living Organisms / Animalia / Craniata / Mammalia / Cetacea / Phocoenidae / Phocoena / Species
Alternative Names
  • Harbour porpoise
  • Delphinus phocoena Linnaeus, 1758; Swedish Seas.
  • Delphinus ventricosus Lacepède, 1804; River Thames.
  • Phocoena tuberculifera Gray, 1865; Margate, Kent.
Description Small rotund body (less than 2 metres long), no beak or forehead, small triangular dorsal fin (B142, D23).



  • 1.4-1.7m / 4.5-5.5ft (D23)
  • Female: about 170cm; male: about 145cm (B142).
  • Neonate: 67-80cm (B142).

External Appearance:

  • Head: short, blunt with no forehead or beak. Upper and lower jaws black.
  • Teeth: small, spade shaped, 19-28 pairs in each jaw
  • Dorsal fin: in centre of back, small and triangular.
  • Colouration: Dorsal dark grey, flanks have paler patch, abdomen white. Grey line jaw-line to flippers.
  • Flippers: short, slightly rounded, black
  • Tail flukes: black, have central notch.
  • (B142)
Range and Habitat Widely distributed coastal waters of temperate and sub-arctic North Atlantic: North Atlantic, North Pacific, Arctic Ocean and Black Sea.
  • British Isles: mainly along Atlantic coasts of south and west Ireland, western Scotland, northern North Sea around north-eastern Scotland.

(B51, B142)


  • British Isles: seen most frequently July to October (B142)


  • Mainly coastal waters (B142).
Further Information Food:

Fish also crustaceans and Loligo cephalopods.

Fish include: Clupea, Ammodytes, Sprattus, Scomber, Sardinea, Micromesistius, Trisopterus, Merluccius, Trachurus, Pollachius, Gadus, Merlangius spp.


Feeding Behaviour: --


  • Young born mainly May to August (can be as early as March).
  • Gestation about 11 months.
  • Lactation about 8 months.
  • Calving interval one to two years.
  • (B142).

Breeding Behaviour: --


  • Mainly slow swimmer, although can reach 22 km/hour.
  • Does not bow-ride.
  • Does not normally leap clear of the water.
  • (B142).

Social Behaviour:

  • Mainly solitary or in small groups.
  • Sometimes large feeding aggregations (e.g. 200-300 individuals).
  • (B142)


  • Declined in southern North Sea and English Channel (B142).

Threats: Drowning in fishing nets, coastal pollution, changes in fish stocks (B142)

Organisations (UK Contacts):

Electronic Library (further reading):

General Legislation:

Individual techniques:

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