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California Gray Whale

Blue Whale

Come See Our Majestic Giants: January - April 2009

Where Do Gray Whales Live?


The Gray Whale (Eschrichtius robustus), more recently called the Eastern Pacific Gray Whale, is a whale that travels between its feeding and breeding grounds each year along the west coast of North America. Gray Whales can reach a length of 46 feet and a weight of up to 36 tons (72,000 pounds). At birth calves are about 15 feet long and weigh close to one ton (2,000 pounds).

Gray Whale Migration

migration chart

The migration route of the Pacific Gray Whale is often described as the longest known mammal migration in the animal kingdom and is easily observed along the California coastline. Beginning in the Bering and Chukchi seas and ending in the warm-water lagoons of Mexico 's Baja peninsula, their round trip journey completes over 12,000 miles.

As ice forms in the arctic, Gray Whales begin their journey south. By mid-December to early January, the majority of the Gray Whales are usually found between Monterey and San Diego, where they are often seen from shore.

By late December to early January, the first of the Gray Whales begin to arrive to the calving lagoons of Baja. These first whales to arrive are usually pregnant mothers that look for the protection of the lagoons to give birth to their calves. On occasion, we see young calves, born early, swimming with their mothers off southern California. By mid-February to mid-March, the bulk of the Gray Whales have arrived in the lagoons including those calves born along the way. It is at this time that the lagoons are filled with nursing, calving, and mating Gray Whales.

Throughout February and March, the first Gray Whales to leave the lagoons are the males and females without calves. Once they have mated, they will begin the expedition back north to their cold water summer feeding grounds which are rich with food. Gray whales are the only baleen whales to feed along the bottom of the seafloor. They scoop up large mouthfuls of sediment and strain small invertebrates through their baleen. Pregnant females and nursing mothers with their newborn calves are the last to leave the lagoons. They leave only when their calves are ready for the journey, which is usually from late March to mid-April.

Human Impact

The only predators of adult Gray Whales are humans and Orcas. After the California Gray Whales' breeding grounds were discovered in 1857, the animals were hunted to near extinction in these lagoons. With the marked decline in Gray Whale numbers, whaling was discontinued on this species. Gray Whales, along with other whale species, have been granted protection from commercial hunting by the International Whaling Commission (IWC) since 1946. The Gray Whale is a conservation success story. Through protection in Mexico 's lagoons the Gray Whale population has recovered and they have been removed from the Endangered Species List. Their population along the East Pacific is estimated to be near 25,000 animals.

Our Cruises

Come aboard the R/V Sea Explorer to observe the Gray Whales during their annual migration. Each cruise is staffed by our naturalists who lead discussions and answer questions about our local wildlife. Learn More >
Cruise Registration

Artwork Copywrighted 2008

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Gray Whale Facts

Order: Cetacea
Suborder: Mysticete (Baleen)
Family: Eschrichtiidae
Species: Eschrichtius robustus
Status: Lower risk
Weight: 14-35 tons