Species: Phocoenoides dalli

Dall's Porpoise

Species

Mammals

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Salish Sea-reliant mammals

Marine mammals of the Salish Sea

Encyclopedia of Puget Sound

Articles:

The decline of Dall’s porpoise in the Salish Sea

Dall’s porpoises have declined in the Salish Sea since the early 1990s for reasons that are unknown. However, the species, which remains abundant in inshore waters of Alaska and in open coastal and offshore waters of the North Pacific Ocean, is not considered threatened or endangered. Major threats to Dall’s porpoise populations include direct hunting, by-catch in fisheries, and the impacts of environmental contaminants.

View of a single black and white Dall's porpoise swimming near the surface of the water.

Southern resident orcas chase and sometimes kill porpoises. Why don’t they eat them?

October 16, 2023

Puzzling encounters between endangered killer whales and harbor porpoises point to questions about prey availability and whale culture, scientists say. Are the whales playing, practicing their hunting skills, or is something else going on?

A killer whale surfaces with its head above water holding a harbor porpoise in its mouth.

Resident killer whales sometimes attack porpoises but never eat them

The mysterious practice of killing porpoises may have a useful function, but it has yet to be fully explained, according to orca researcher Deborah Giles.

A 6-year-old killer whale from L pod, known as L-73, chases a Dall’s porpoise in this historical photo taken in 1992. Photo: Debbie Dorand/Center for Whale Research

Harbor porpoise in the Salish Sea

In the 1940s, harbor porpoise were among the most frequently sighted cetaceans in Puget Sound, but by the early 1970s they had all but disappeared from local waters. Their numbers have since increased, but they remain a Species of Concern in the state of Washington. This in-depth profile looks at harbor porpoise in the Salish Sea, and was prepared by the SeaDoc Society for inclusion in the Encyclopedia of Puget Sound.

Harbor porpoise surfacing. Photo: Erin D'Agnese, WDFW

Population structure and intergeneric hybridization in harbour porpoises Phocoena phocoena in British Columbia, Canada

October 30, 2014

A 2014 paper in Endangered Species Research suggests that harbour porpoises inhabiting coastal waters of southern British Columbia constitute a single genetic population, which should be reflected in management decisions.

Harbor porpoise (Phocoena phocoena). Photo courtesy of National Park Service.

Classification

Kingdom

Animalia

Phylum

Craniata

Class

Mammalia

Order

Cetacea

Family

Phocoenidae

Genus

Phocoenoides

NatureServe

Source:
ELEMENT_GLOBAL.2.105734

Classification

Other Global Common Names

marsouin de Dall

Informal Taxonomy

Animals, Vertebrates - Mammals - Whales and Dolphins

Formal Taxonomy

Animalia - Craniata - Mammalia - Cetacea - Phocoenidae - Phocoenoides - -type in the North Pacific (see IUCN 1991).

Ecology and Life History

Habitat Type Description

Marine

Migration

false - false - false - Details of migrations are poorly known. Year-round resident thoughout much of range, but generally moves north for summer, south for winter. Migrations into Bering Sea may occur spring though fall. Inshore movements may augment populations off California in winter and spring (Leatherwood and Reeves 1983).

Non-migrant

false

Locally Migrant

false

Food Comments

Eats squid, crustaceans, and various fishes (saury, hake, herring, jack mackeral, and mesopelagic, bathypelagic, and deep-water benthic species) (Leatherwood and Reeves 1983). Feeds mainly on epi- and meso-pelagic squids and small schooling fishes (Jefferson 1988).

Reproduction Comments

Single calf is born mainly late June-September, though births may occur year-round in the eastern North Pacific. Gestation estimates: 7-9 months, 11.4 months. Calves nurse for a few months. Not all adult females become pregnant every year; nonbreeders may segregate from breeders. Males are sexually mature at 5-8 years, females at 3-7 years, depending on location. Most live less than 13 years.

Ecology Comments

Usually travels in groups of 10-20 (also reported as 2-12), though aggregations of at least 200 (or thousands) have been reported. Frequently in association with Pacific white-sided dolphins or pilot whales (Leatherwood and Reeves 1983, Jefferson 1988).

Length

2200

Weight

220000

Conservation Status

NatureServe Global Status Rank

G4G5

Global Status Last Reviewed

1997-04-09

Global Status Last Changed

1997-04-09

Distribution

Conservation Status Map

Global Range

North Pacific: infrequent north of 62 degrees North in Bering Sea; in west, north of Choshi and east-central Honshu, Japan, and in the Sea of Japan and southern Okhotsk Sea; in east, north from about 28 degrees north (usually north of 32 degrees North). TRUEI morph is most abundant off the Pacific coast of northern Japan and off the Kuril Islands.

ELEMENT_GLOBAL.2.105734