Baleen whales have changed their distribution in the Western North Atlantic. Researchers using passive acoustic recordings of whale calls to track their movements have found that four of the six baleen whale species found in the western North Atlantic Ocean -- humpback, sei, fin and blue whales -- have changed their distribution patterns in the past decade. The recordings were made over 10 years by devices moored to the seafloor at nearly 300 locations from the Caribbean Sea to western Greenland. Source 8j.