There are two openings to the nasal passage divided by an external central septum but these are internal. The whale has no dorsal fin but it has a distinct triangular or rounded hump two-thirds along the body followed by a spinal ridge to broad triangular and deeply notched tail flukes. A thick 'keel' not seen in many whales runs along the underside of the tail stock. The Sperm whale is cosmopolitan in deep waters of all seas except close to ice edges. Winter is spent in temperate and tropical waters.
Some populations are resident year-round.
Feeding areas include deeper waters around the Aleutian Islands in North Pacific, off New Zealand, Peru and Chile in the South Pacific, Newfoundland Grand Banks and the continental slope west of the British Isles, north towards Iceland in the North Atlantic, east coast of South America from Argentina to the Faulkland Islands and around Tristan da Cunha in the South Atlantic. Mating and calving areas include waters off New Guinea and around Hawaii in the North Pacific, deep waters off East Australia, Galapagos and Ecuador in the South Pacific, around the Bahamas, the Azores and Madeira in the North Atlantic, off Brazil, Angola and Southwest Africa in the South Atlantic, off Western Australia, around Madagascar, and west and north of Seychelles to the coasts of India, Sri Lanka and the Arabian peninsula in the Indian Ocean.