The gray whale (Eschrichtius robustus), also known as the grey whale, gray back whale, Pacific gray whale, or California gray whale, is a baleen whale that migrates between feeding and breeding grounds yearly. It reaches a length of 14.9 meters (49 ft), a weight of 36 tonnes (40 short tons), and lives between 55 and 70 years. The common name of the whale comes from the gray patches and white mottling on its dark skin. Gray whales were once called devil fish because of their fighting behavior when hunted. The gray whale is the sole living species in the genus Eschrichtius, which in turn is the sole living genus in the family Eschrichtiidae. This mammal descended from filter-feeding whales that appeared at the beginning of the Oligocene, over 30 million years ago. The gray whale is distributed in an eastern North Pacific (North American), and an endangered western North Pacific (Asian), population. North Atlantic populations were extirpated (perhaps by whaling) on the European coast before AD 500, and on the American coast around the late 17th to early 18th centuries. Even so, on May 8, 2010, a sighting of a gray whale was confirmed off the coast of Israel in the Mediterranean Sea, leading some scientists to think they might be repopulating old breeding grounds that have not been visited for centuries. In May and June 2013, a gray whale was sighted off the coast of Namibia – the first confirmed in the Southern Hemisphere. The round-trip journey of one gray whale has set a new record for the longest mammal migration, covering a distance of more than 22,000 kilometres across the Pacific Ocean. Her migration has shown new insight into how endangered species are making drastic changes in their life style.
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