Longest mammal migration raises questions about distinct species, April 17

A team of scientists from the United States and Russia has documented the longest migration of a mammal ever recorded – a round-trip trek of nearly 14,000 miles by a whale identified as a critically endangered species that raises questions about its status. The researchers used satellite-monitored tags to track three western North Pacific gray whales from their primary feeding ground off Russia’s Sakhalin Island across the Pacific Ocean and down the West Coast of the United States to Baja, Mexico. One of the tagged whales, dubbed Varvara (which is Russian for Barbara), visited the three major breeding areas for eastern gray whales, which are found off North America and are not endangered. Results of their study were published by the Royal Society in the journal Biology Letters.