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Marine Mammals

Whales, Dolphins, Porpoises, Seals &Sea Lions, Sea Otter & River Otter

Phylum Chordata

Illustrations by Pieter Folkens

Whales, Dolphins, Porpoises

Harbour Porpoise

Phocoena phocoena

To 6’3” (1.8 m) long. Weight to 145 lb. (65 kg). Low, triangular dorsal fin. Small rounded head. Dark back, light sides to white, speckled belly. Solitary or in pairs, in coastal areas year-round. Avoids vessels; does not bow-ride.

Dall’s Porpoise

Phocoenoides dalli

To 7’3” (2.2 m) long. Weight to 485 lb. (218 kg). Hooked, triangular dorsal fin, often with white patch. Thick body, grey to black with white patch on sides and belly. Common and abundant. Fast swimmer; creates “rooster tail” splash.

Pacific White-Sided Dolphin

Lagenorhynchus obliquedens

To 8’ (2.4 m) long. Weight to 300 lb. (135 kg). Tall, curved dorsal fin, black and grey. Black back with pale grey streak along sides, widening at tail end. Most abundant dolphin in north Pacific. Fast swimmer, leaps and creates “rooster tail” splash. In groups of 50 to several hundred.

Orca (Killer Whale)

Orcinus orca

Female to 23’ (7 m), 4.5 tons (4 tonnes), short curved dorsal fin to 3’ (90 cm). Male larger, to 30’ (9 m) and 6 tons (5.4 tonnes), tall dorsal fin to 6’ (1.8 m). Black with white chin, white patches behind eye and on sides. Dorsal fins and distinctive saddle patches behind dorsal fin used for identification. Family groups have unique vocalizations. Nearshore pods (5–50 animals) of resident orcas feed only on fish. Small pods (2–10 animals) of transient orcas are mammal hunters. Offshore orcas (pods to 25 or more animals) are likely fish eaters, especially sharks.

Gray Whale

Eschrichtius robustus

To 50’ (15 m) long. Weight to 35 tons (31.5 tonnes). Long, slender head. A baleen whale (feeds by straining food through baleen plates in the jaws). Upper jaw has coarse yellow baleen. Grey body with lighter patches and mottling, scattered patches of white barnacles and orange whale lice. Low dorsal “hump,” followed by 6 to 12 “knuckles.” Marks on body sides and tail flukes are used to identify individuals. In shallow coastal waters; whales breed in shallow lagoons of Baja and migrate annually to Arctic seas.

Humpback Whale

Megaptera novaengliae

To 49’3”(14.8 m) long. Weight to 44 tons (40 tonnes). Large head with small knobs. A baleen whale. Low, stubby dorsal fin with broad base. Long, slender flippers. Grey to black body with lighter underside. Alone or in groups of 20 or more. Swims actively, breaching, spy-hopping and rolling on back to wave flippers. Many feeding behaviours, lunging and bubble-netting. Colour and shape of underside of tail flukes are used to identify individuals.

Seals, Sea Lions

Pacific Harbour Seal

Phoca vitulina richardsi

Male and female to 6’ (1.8 m) long. Weight to 250 lb. (113 kg). Large, round, smooth head without external ear flaps. Short, furry front flippers. Grey to black, mottled. Often hauls out on rocks and sand or mudflats.

Steller Sea Lion

Eumetopias jubatus

Female to 8’ (2.4 m), 600 lb. (270 kg); male to 10’ (3 m), 2,200 lb. (990 kg). Ear flaps; low forehead. Large front flippers to sit erect. Male tan above and reddish brown below; female slimmer and uniformly brown. Roars and growls, does not bark. Hauls out on rocks.

California Sea Lion

Zalophus californianus

Female to 5’8” (1.7 m), 250 lb. (113 kg); male to 8’ (2.4 m) and 900 lb. (405 kg). Ear flaps. Smaller and darker than Steller sea lion. Mature male dark brown to tan, light-coloured bump on forehead. Female blonde to tan. Barks. Hauls out on rocks, logs and docks. Males and the occasional female migrate north of the breeding grounds in California and Mexico.

Sea Otter, River Otter

Sea Otter

Enhydra lutris

To 5’ (1.5 m) long. Weight to 80 lb. (36 kg). Short, flattened tail. Short, thick neck and flat, broad head. Large, webbed hind feet. Tan or rusty red to dark brown or black, with light-coloured head. Squeals, hisses and grunts. Uses rock as a tool while eating and floating belly-up. Often swims on its back. Typically in open, exposed waters, solitary or “rafts” in kelp beds. Clumsy on land, seldom leaves the water.

River Otter

Lutra canadiensis

To 4’6” (1.4 m) long. Weight to 30 lb. (13.5 kg). Long, round, tapered tail. Slender body and long neck, small, webbed hind feet. Short, dense dark fur above, lighter below. Unique whistle. Often swims belly-down. At home on land.