Mammals
Gray Whale
Eschrichtius robustus · also called grey whale
Rolling onto its side along the shallow seafloor, a gray whale scoops up a mouthful of sediment and filters out small invertebrates through its baleen, midway through one of the longest annual migrations of any mammal on Earth.
Overview
The gray whale, Eschrichtius robustus, is a large baleen whale native to coastal and open ocean waters across the North Pacific, migrating annually between Arctic feeding grounds and coastal lagoons in Mexico. Its extraordinarily long migration, unusual bottom-feeding strategy, and dramatic recovery from near extinction through historical whaling make it one of the more conservation-significant and behaviourally distinctive large whales found anywhere in the world.
A whale that feeds from the ocean floor
While most baleen whales strain prey from open water, the gray whale instead rolls onto its side and works the seafloor directly, a distinctive feeding strategy that sets it apart from nearly every other large whale species.
Status
Least Concern in the recovered eastern Pacific population, though a much smaller, separate western Pacific population remains considerably more vulnerable and closely monitored.
Gray Whale: common questions
How far does the gray whale migrate each year?
This species undertakes one of the longest migrations of any mammal, travelling thousands of miles each year between Arctic and subarctic feeding grounds and warm coastal breeding lagoons in Mexico, an annual round trip covering an enormous distance along the Pacific coastline.
How does the gray whale feed differently from other baleen whales?
Unlike many baleen whales that filter prey from open water, this species typically feeds by rolling onto its side and scooping sediment directly off the ocean floor, filtering out small invertebrates through its baleen plates, an unusual bottom-feeding strategy among large whales.
Has the gray whale recovered from historical whaling?
The eastern Pacific population has recovered substantially following intensive hunting during the 19th and 20th centuries that reduced numbers dramatically, thanks to international protection, though a separate, much smaller western Pacific population remains considerably more vulnerable and closely monitored.
Why does the gray whale travel to specific lagoons to give birth?
This species travels to particular warm, sheltered coastal lagoons in Mexico specifically to give birth, providing newborn calves with a relatively safe, predator-reduced environment to build strength during their earliest and most vulnerable weeks before the long migration back north.