Averaging at 1.7 metres, the harbour porpoise is one of the smallest whales in Canada and is even smaller than the average human!

On this page, you will learn about the life cycle of this wildlife species. You can access different types of information about this species and how it relates to the Species at Risk Act.

The subspecies present along the Atlantic coast of Canada is Phocoena phocoena phocoena; the subspecies present on the Pacific coast is P. p. vomerina.

Harbour Porpoises are among the smallest whales; in eastern Canada few individuals exceed 1.7 m in total length. Females are larger than males, and typically reach lengths of about 160 cm and weights of 65 kg. Like all porpoises, they have rounded heads that lack an obvious rostrum or beak. A small, triangular dorsal fin is located at about the middle of the back. The sides are a mottled greyish-white and fade to an almost white ventral surface. A black cape extends over the back and sides, although its extent varies considerably among individuals and populations. Individuals may also have dark patches on their faces. There is no difference in coloration between males and females, but the calves are usually darker than the adults.

Harbour Porpoises are widely distributed over the continental shelves of the temperate northern hemisphere, with two populations in Canada. On the west coast, members of the Pacific Ocean population occur throughout the coastal waters of British Columbia. On the east coast, members of the Northwest Atlantic population are found from the Bay of Fundy north to Cape Aston, at approximately 70° N, and south to North Carolina. The Harbour Porpoise Northwest Atlantic population is made up of four discrete sub-populations; three in Canadian waters (Newfoundland-Labrador, Gulf of St. Lawrence, and Bay of Fundy-Gulf of Maine), and one off the western coast of Greenland. There are no range-wide estimates of the abundance of Harbour Porpoises in eastern Canada, but it seems likely that the Northwest Atlantic population is greater than 50 000 individuals. is known about the role of disease in the natural mortality of Harbour Porpoises, but many emaciated, dead juveniles are found stranded along the east coast of the United States each spring, apparently having starved to death. Harbour Porpoises are occasionally observed in large aggregations, usually associated with high prey concentrations, but they are typically seen in small groups of a few individuals. Observations indicate that the social groupings are fluid, and that individual porpoises sometimes use the same habitat in consecutive years. Harbor Porpoises are shy animals that do not respond well to being kept in captivity, and intensive human activities in coastal waters may have a negative effect on their populations.

The most important recent threat to Harbour Porpoises in eastern Canada is bycatch in bottom-set gill nets used to capture groundfish; this threat has decreased substantially with the depletion of groundfish stocks and consequent reductions in fishing. Other potential threats include: habitat degradation; loss of habitat resulting from the use of acoustic harassment devices, particularly around Salmon aquaculture sites; and environmental contamination by organochlorines (OCs) and polychlorinated biphenyls (PCBs).

SARA contains provisions that allow for the protection of certain listed species at risk individuals, their residences as well as their critical habitat. The responsibility for conservation of species at risk is shared by all jurisdictions in Canada. The Act recognizes this joint responsibility and that all Canadians have a role to play in the protection of wildlife. More information about SARA, including how it protects individual species, is available in A guide to your responsibilities under the Species at Risk Act. For information on how provincial or territorial laws protect the species, consult the provinces’ and territories’ websites.