Kingdom: Animalia, Phlyum: Chordate, Class: Mammalian, Order: Cetacean, Family: Physeteridae, Genus: Physeter, Species: macrocephalus.
The Sperm Whale was listed as endangered on June 2, 1970 under the Endangered Species Conservation Act of 1969. It is also protected under the Marine Mammal Protection Act of 1972.
The Sperm Whale is the largest of the toothed whales. It is one of the most well known members of the whale family, being represented in toys and drawings; Moby Dick was a sperm whale. Its distinctive feature is its large, blunt head. This head contains spermaceti, which is a substance that is widely used for candles and ointments.
Sperm whales are the most sexually dimorphic cetaceans. The males are considerably larger than the females. Adult females may grow up to 36 feet and weigh up to 15 tons, while their male counterparts grow up to 52 feet and weigh as much as 45 tons. Its large head takes up 25 to 35% of it total body length. They have the largest brain of any animal, an average of 17 pounds in mature males. Sperm whales are the only living cetaceans that have a single blowhole asymmetrically situated on the left side of the head near its tip.
Sperm whales do not travel in mixed groups of males and females like other whales. Instead they form harems consisting of a bull leading group of adult females and their offspring. Adult males that are without harems travel in bachelor groups. Adult males can only obtain a harem by fighting a defeating a bull that leads one. “Mixed groups” or “nursery schools” are made up of about 25 individuals, nursing females, calves and some juveniles.
The males compete with one another in early spring and summer for the control of a group of mature females. A successful male mates with all of the females in its harem. Gestation lasts for about 15 months. Calves are 12 to 16 feet when born and nurse for about two years. Females reproduce only once every four years.
Female sperm whales...