link to text navigation
Marine Mammal Commission Web site Banner

North Pacific Right Whale (Eubalaena japonica)

North Pacific Right Whale
North Pacific Right Whale (Photo: Brenda Rone)

North Pacific right whales, like right whales in the North Atlantic Ocean, were severely depleted by commercial whaling and are now among the world's most endangered mammals. Two populations are thought to survive, one in the western North Pacific off Russia and the other in the eastern North Pacific off Alaska. The status of both populations is poorly known. The western population is thought to number in the low hundreds although reliable information to support that estimate has not been published. The eastern population appears to number a few tens of animals, making it the most endangered marine mammal population in U.S. waters.

Early in the 1960s the eastern population apparently numbered in the low hundreds and presumably was recovering slowly. However, between 1962 and 1967 Soviet whalers killed more than 350 animals in the southeastern Bering Sea and Gulf of Alaska, despite an international ban on the hunting of all right whales. It appears that this illegal whaling virtually eliminated the population. Between the late 1960s and the mid-1990s sightings of right whales in the eastern North Pacific were rare, widely scattered, and almost always involved solitary animals. Then, in the summer of 1996, a group of four animals was reported in the southeastern Bering Sea. Each year since then, the National Marine Fisheries Service has undertaken aerial, shipboard, and/or acoustic surveys of the area during the summer.

Range and Habitat:

Sea of Okhotsk and the Kuril Islands east through the Bering Sea and the Aleutians to the Gulf of Alaska

Status under Law:

Endangered (ESA)

Conservation issues:

Critically small population size, entanglement in fishing gear, offshore oil and gas exploration and development

Physical characteristics:

At Birth At Maturity
Length 4-4.6 m
17-18.3 m
Weight 910 kg
(2,000 lb)
Up to 90,000 kg
(200,000 lb)


Known to exceed 70 years

Annual Report:

For more information, see the North Pacific Right Whale section from the 2002 Annual Report

Download a copy: PDF (154 KB)

Additional Links:

National Marine Fisheries Service - Stock Assessment Reports

Alaska Fisheries Science Center - Detecting Right Whales Using Passive Acoustics in SE Bering Sea


Marine Mammal Commission Home page About the Marine Mammal Commission About the Commission The Library Calendar Site Index Our Staff About this Site Job Vacancies To Contact Us Privacy Notice Disclaimer

Revised | Questions, Comments? Contact Us | How To Find Our Office | Report Error On This Page | Site Index | Marine Mammal Commission