In 2015, a 9-year-old female gray whale (Eschrichtius robustus) named Varvara broke the record for the longest-migrating mammal when she swam nearly 14,000 miles (22,531 km) from Russia to Mexico and back again. The journey lasted 172 days (over 5.5 months), taking her from the gray whales’ feeding grounds off Sakhalin Island, across the Bering Sea and the Gulf of Alaska, and down the west coast of North America, ending up off the coast of Baja California, where gray whales breed in the warm lagoons. Then she swam back to Russia.
Six other gray whales were also given satellite-monitoring tags by researchers from the Marine Mammal Institute at Oregon State University, though none of the other tags remained intact for the entire migration. Amazingly, Varvara took a somewhat different route on each leg of her journey, demonstrating excellent navigational skills that didn’t require her to hug the coastline. Even more incredibly, after leaving Russia, she didn’t feed at all during the long journey to Mexico and back.
Gray whales are far from the only animals to migrate thousands of miles each year. Before Varvara’s journey in 2015, the record holder for the longest mammal migration was a humpback whale that traveled 11,706 miles round trip in 2011, from Hawaii to Alaska and back. Along with their calves, humpback whales make the journey in the summer to feed on krill and small fish in the cool Alaskan waters.
Amazing animal journeys:
- Other ocean creatures migrate vast distances, too. A great white shark is estimated to have traveled over 12,400 miles round trip between South Africa and Australia in 2003. Leatherback turtles regularly migrate over 6,000 miles to find a suitable beach for laying eggs, though sometimes they travel much farther.
- In North America, Porcupine caribou travel up to 1,500 miles round trip from boreal forests in Canada and Alaska to the continent's northern reaches in an effort to find food and stay cool during the summer.
- In gigantic herds that can stretch as long as 25 miles, blue wildebeest travel up to 1,000 miles around the Serengeti in a circular migration that marks the end of the rainy season. Unlike wildebeest, plains zebra complete a linear migration, a round-trip between Namibia and Botswana that is more than 300 miles. Both wildebeest and zebras encounter an increasing number of manmade obstacles such as fences and roads that fragment their habitat and pose challenges during migration.