An intrepid western grey whale—an endangered species that was once thought to be extinct—has just broke the world record for longest mammal migration.
The western grey whale, named Varvara, which means Barbara in Russian, travelled across the Pacific Ocean from Russia to Mexico and back again. Completed between 2011 and 2013, the total trek round-trip came in at a record-smashing 22,000 kilometers.
Varvara is one of three western grey whales that are being tracked by a team of Russian and American scientists, who are monitoring the whales via satellite tagging devices.
Varvara started her journey from the grey whales’ primary feeding ground off of Sakhalin Island in Russia, then made her way to Mexico. Along the coast of North America, she visited the three major reproductive areas of the eastern grey whale, a species that is a close relative to the western grey whale but is not considered endangered.
In a new research paper by the scientists, they write, “[Varvara’s] 22,5011-kilometer round-trip is the longest documented mammal migration and strongly suggests that some presumed western great whales are actually eastern grey whales foraging in areas historically attributed to western grey whales.”
The paper continues: “Despite evidence of genetic differentiation [between the western and eastern grey whale], these tagging data indicate that the population identity of whales off Sakhalin Island needs further evaluation.”
This means that although the current population of western grey whales is around 150, that number could be inaccurate as eastern grey whales could be masquerading as their endangered counterparts, and vice versa. With this information, the scientists will continue to monitor the western grey whales for a more accurate population figure.
The western grey whale was thought to be extinct until a cluster of the whales was discovered living off of Sakhalin Island. Meanwhile, thanks to conversation efforts, the eastern grey whale’s population has rebounded and is currently around 18,000.
Gray whales, once called “devil fish” because of their aggressive fighting behavior when threatened, are an ancestor of the filter-feeding whales from the beginning of the Oligocene epoch more than 30-million years ago.
The International Whaling Commission has been protecting both species of gray whales from commercial hunting since 1949.