Gray Whale

Marine Creature:  Gray Whale (Eschrichtius robustus)   

Kindly compiled by Rianna from Whalelab & The Society of Ecological and Coastal Research (SEACR) 

General Description

The gray whale, Eschrichtius robustus, is a baleen whale that migrates between feeding and breeding grounds yearly. The common name of the whale comes from the gray patches and white mottling on its dark skin.  The gray whale is a dark slate-gray in color and covered by characteristic gray-white patterns; scars left by parasites which drop off in its cold feeding grounds. Individual whales are typically identified using photographs of their dorsal surface and matching the scars and patches associated with parasites that have fallen off the whale or are still attached.


The eastern Pacific population occur in the eastern North Pacific and Amerasian Arctic Oceans, migtrating from breeding and calving ground in lagoons of Baja California Sur, Mexico and feeding grounds of the Bering and Chukchi Seas. Also a western Pacific population occurs off Russia, Japan, Korea and China, primarily feeding on the north eastern coast of Sakhalin Island.

Interesting Facts

The gray whale is the only living species in the family Eschrichtiidae.
Gray whales are heavily infested with external parasites and commensals, more than any other cetacean, but they are not known to be harmful.


Mating is promiscuous with both sexes copulating with several partners. Sexual Maturity is from 6-12 years. Mating and calving is seasonal, where mating occurs during the southern migration. Estimates for gestation are 11-13 months, with cows bearing single calves once every 2 years or more

  • Food: Invertebrates/Zooplankton
  • Lifespan: unconfirmed
  • Size: 16-45,000kg

gray2Feeding & Hunting

Typically feeding in the Arctic, they are suction feeders feeding on benthic invertebrates, but will feed opportunistically on epi-benthic and pelagic zooplankton.


For the western Pacific population – Sakhalin Island foraging habitat lies within a region undergoing massive oil and gas development. Populations are struggling to recover from commercial whaling due to a low number of reproductive females and low juvenile survival
For the eastern Pacific population – predation threat from killer whales on juveniles


Conservation Status & International Protection

Protected from commercial whaling under the 1937 International agreement for the Regulation of Whaling, and the 1946 International convention for the regulation of whaling.

The western Pacific gray whale is one of the most critically endangered populations of whales (CR in the IUCN Red List), whereas In 1994, eastern north Pacific gray whales were delisted from the U.S. Endangered Species Act’s List of Endangered and Threatened Wildlife because they are no longer considered depleted

How can people help?

Become better educated and support their protection and conservation for their key habitats.

Best places in the world to see these creatures:

The eastern Pacific population supports a major whale watching industry both in breeding ground of Mexico (Baja California) and more northern foraging grounds.  For more information and ethical whale watching trips visit

Scientist Profile:    Rianna from Whalelab & The Society of Ecological and Coastal Research (SEACR)


The Society of Ecological and Coastal Research (SEACR)

seacaDescription/Background of work

The mission of SEACR is twofold:
1. To provide individuals with the educational opportunity to assist marine ecological researchers with their field research data collection;
2. To provide scientific researchers with logistical and financial support throughout their field season.
Throughout the history of our research projects we have tried to illuminate a variety of views of marine mammals including socio-cultural studies and management, currently, however, our studies are aimed at ecological matters.

Volunteer/Paid Work Opportunities

Annual summer internships programmes working in the field as research assistants. Visit Whalelab for info…

Naturalist Course

This course is an excellent opportunity for an individual working towards a job in the marine ecotourism industry. Marine interpretation is fun and challenging work, but it is not for everyone. It is, however, an experience that delivers a unique opportunity for community education and enjoyment of wildlife. Upon completion of the course participants will receive a course pack, a recommended reading list, and a certificate recognized by Professional Whale Watching Operators on the coast. Visit Whalelab for more info…


Return to Baleen Whales or learn more about the Blue Whale