North Pacific Right Whale

Eubalaena glacialis
Family: Balaenidae
North Pacific Right Whale

Illustration © Pieter Folkens

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right whale range map

Distribution/Migration: Northern Hemisphere. Migratory patterns are unclear. Historically, south Bering Sea and Gulf of Alaska were primary summer range. May winter as far south as Baja California. Circles show areas with recent repeated sightings. Pink shows summer range.

This web page is modified from the book Marine Mammals of Alaska by Kate Wynne, illustrated by Pieter Folkens, available at the Alaska Sea Grant Bookstore.

Marine Mammal Guide

SIZE: Max length 56 ft (17 m), average wt 60 tons. Females larger than males. Length at birth 15–20 ft (4.6–6 m).

BODY: Robust body with large head (one fourth body length). Bowed lower lips enfold narrow, arching rostrum. Callosities (wart-like growths) on the rostrum, lower lip, and around the eyes. Up to 250 dark baleen plates per side, each to 9 ft (2.8 m) long. Flippers broad and spatulate. Wide flukes with smooth edges and deep notch.

COLOR: Predominantly black, some white patches on belly.

DORSAL FIN: No dorsal fin.

BLOW: V-shaped, bushy, to 16 ft (5 m) high.

BEHAVIOR: Docile. Slow swimmers but are more acrobatic than bowheads (often breaching, flipper slapping). Vocalization is variety of moans and burps.

DIVE PATTERN: Blow 5–10 times at 15–30 sec intervals, then dive for 5–15 min. Usually show flukes before deep dives.

HABITAT: Mostly temperate and subpolar waters. Calving may occur in shallow bays and coastal waters.

FOOD HABITS: Zooplankton specialists: primary prey is euphausiids and copepods, gathered by skimming through schools with mouth agape.

LIFE HISTORY: Uncertain but probably breed in winter–spring at low latitudes and calve the following winter after gestation of 12 months. Single calf every 2–4 yrs. Lactation lasts 1 yr.

STATUS AND HUMAN INTERACTIONS: Critically endangered. Populations were decimated by commercial whalers who named it the right whale because it is easily approached, floats when killed, and is rich in oil. Completely protected in U.S. waters since 1967 but population remains critically low (probably <100). A sighting of 17 right whales in west Bristol Bay in July 2004 included a female and 2 calves.