Range and Habitat
They are found worldwide in temperate and tropical waters, usually in deep waters rather than close to land. As well as the tropical parts of the Indian, Pacific and Atlantic Oceans, Rissos are also found in the Persian Gulf, Mediterranean and Red Seas, but not the Black Sea. They range as far north as the Gulf of Alaska and southern Greenland and as far south as Tierra del Fuego.
Their preferred environment is just off the continental shelf on steep banks with water depths varying from 400–1,000 meters (1,300–3,300 ft) and water temperature at least 10 °C (50 °F) and preferably 15–20 °C (59–68 °F).
The population around the continental shelf of the United States is estimated in excess of 60,000. In the Pacific a census recorded 175,000 individuals in eastern tropical waters and 85,000 in the west. No global estimate exists.
Read more about this topic: Risso's Dolphin
Famous quotes containing the words range and/or habitat:
“The more the specific feelings of being under obligation range themselves under a supreme principle of human dependence the clearer and more fertile will be the realization of the concept, indispensable to all true culture, of service; from the service of God down to the simple social relationship as between employer and employee.”
—Johan Huizinga (1872–1945)
“Neither moral relations nor the moral law can swing in vacuo. Their only habitat can be a mind which feels them; and no world composed of merely physical facts can possibly be a world to which ethical propositions apply.”
—William James (1842–1910)