Gray Whale Swims 13,988 Miles In Pacific, Breaks Migration Record

(CBS) - The western gray whale now holds the record as the mammal with the longest known migration, researchers say.

A female western gray whale swam from Russia to Mexico and back again -- a total of 13,988 miles - in 172 days, according to a new report.

Until now, the title of the longest-migrating mammal belonged to the humpback whale (Megaptera novaeangliae), which migrates up to 10,190 miles (16,400 km) round trip as it travels between its breeding grounds near the equator and the food-rich waters of the Arctic and Antarctic, according to Guinness World Records.

CBS News has a complete report - and a map - of how the historic journey of Vavara the whale was tracked.