WHERE TO FIND THEM
The Sperm whale (Physeter macrocephallus) is the deep-sea leviathan made famous by Herman Melville’s Moby Dick.
It can be found in most seas except the high Arctic and winter is spent in temperate and tropical waters. Some populations are resident year-round as fundamentally they are not a migratory species.
Feeding areas include the deeper waters around the Aleutian Islands 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 Falkland Islands and around Tristan da Cunha in the South Atlantic.
Mating and calving areas include waters off Papua 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.
WHAT TO LOOK FOR
Also known as the great sperm whale and Cachalot, sperm whales have a single blowhole on the left side near the front of their huge square head, which comprises nearly one third of the animal’s overall length. Inside this giant head is the largest brain of any known creature on earth.
When they breathe out at the surface, their blow sprays forward to the left. They can often be seen breaching and lob tailing – extending their flukes in the air just prior to submersion – but dive for long periods at a time, sometimes up to 2 hours and 3.3km deep, to search for squid their staple food.
They have a low hump instead of a dorsal fin and are covered in dark wrinkled skin. They are the largest of the toothed whales, reaching a length of 18.5 metres in males and 12.5 metres in females. Adults can weigh anything between 20 and 50 tonnes.
They spend most of their lives separated into group either adult females with male and female young or males between 7 and 27 years of age. Older males tend to live on their own or in very small groups and join females in the breeding season.
NUMBERS
The IUCN Red List of Threatened Animals is a guide produced every two years by the International Union for Conservation of Nature and Natural Resources. The main purpose of the list is to catalogue the species that are regarded as threatened at global level – overall extinction.
While the next list is not available until the end of March 2002, the organisation told deeperblue that figures for whales remain unchanged since 2000.
It is not known exactly how many Sperm whales are alive today. They were over-hunted for many years primarily for their meat and oil, but anti-whaling laws have allowed a recovery in numbers and the 2000 Red List classifies the species as vulnerable, meaning it is not critically endangered but facing a high risk of extinction in the wild in the medium-term future.
