Harbour seals are one of the most widespread of the pinnipeds. They are found throughout coastal waters of the Northern Hemisphere, from temperate to Polar Regions. Five subspecies are recognized: P. v. vitulina occurs in the eastern Atlantic from Brittany to the Barents Sea in north-western Russia and north to Svalbard, with occasional sightings as far south as northern Portugal; P. v. concolor occurs in the western Atlantic from the mid-Atlantic United States to the Canadian Arctic and east to Greenland and Iceland; P. v. mellonae only lives in a few lakes and rivers in northern Quebec, Canada, that drain into Hudson and James Bays (geological changes prohibit these seals from leaving this freshwater habitat); P. v. richardii is found in the eastern Pacific from central Baja California, Mexico to the end of the Alaskan Peninsula and possibly to the eastern Aleutian Islands, and; P. v. stejnegeri ranges from either the end of the Alaskan Peninsula or the eastern Aleutians to the Commander Islands, Kamchatka and through the Kuril Islands to Hokkaido in the western Pacific.