Which whale species has the longest known migration?

The gray whale has the longest known migration of any whale species, traveling roughly 10,000 miles (16,000 kilometers) round trip each year.

Gray whales migrate between summer feeding grounds in the Arctic and winter breeding and calving lagoons along the coast of Baja California, Mexico. Their route follows the western coast of North America, making the journey unusually visible to people on shore.

The migration is driven by seasonal needs: gray whales feed in productive northern waters during summer, then move south to warmer, sheltered lagoons where calves are born. They mostly eat small bottom-dwelling animals by filtering sediment through their baleen.

Humpback whales are also famous for enormous migrations, and individual humpbacks have occasionally traveled extraordinary distances between ocean basins. However, the gray whale remains the standard answer for the longest regular annual whale migration. Gray whales can sometimes cover more than 14,000 miles in a year.