RANGE/HABITAT:

    The blue whale is found mostly in cold and temperate waters. It prefers deeper ocean waters to coastal waters.The blue whale occurs in the Icelandic & Celtic Marine Ecosystems, Southern Caribbean Sea, and Sea of Cortez Global 200 Ecoregions. Also, approximately 2,000 blue whales live off the California Coast and migrate to Mexico, and Costa Rica.
(Olson & Dinerstein 1998, Olson & Dinerstein 1999)

History of Distribution

     The blue whale is found in all major oceans of the world. Its populations have been severely depleted throughout its range due to commercial whaling, which ceased in 1964. There have been reports of increased sightings in some areas (for example, in 1988, blue whales were seen off of Jan Mayen Island, 1000 km (620 mi) west of Norway, for the first time in 30 years).  Furthermore, there are trends of increase around Iceland and offshore of the west coast of the USA. 

     On the other hand, the number of blue whales in the Antarctic remains extremely low; there is a complete absence of blue whales off southern Japan, and blue whales are apparently rare in the Gulf of Alaska and the southern Bering Sea, (a major Orca population habitat) where they were once abundant.  (Klinowska 1991, Reeves et al. 2003)