セミクジラ
Most recent sightings and acoustic records of right whales in the eastern part of their range have come from a relatively small area in the southeastern Bering Sea. Most of these records are within, or near, the U.S. designated Critical Habitat for the North Pacific Right whale. A much smaller number of sightings has come from the Gulf of Alaska and the coasts of British Columbia and further south. The very small number of North Pacific right whale calls detected during the NMFS acoustic research—hundreds per year contrast with the vastly greater number (hundreds of thousands) of bowhead whale calls during migration in the western Arctic and blue whale calls off California—further reinforces the conclusion that the population size of North Pacific right whales in the Bering Sea is very small.