Physeter macrocephalus - Cachalot - Capodoglio - Sperm whale
Illustration © M. Würtz. Musée océanographique de Monaco, Fondation Albert Ier

Sperm whales measure up to 18 m long and can weigh 40 tons, making them one of the odontocetes. They have a unique physical appearance, with a prominent head that can account for as much as a third of their length and that contains a special oil known as ‘spermaceti’. The oil varies in density depending on the degree to which it is heated by the blood – this enables sperm whales to regulate their buoyancy when diving. They live in the open sea or above the continental shelf, alone or in small groups (five at most). The undisputed kings of freediving, they can dive down to more to than 2,000 m and remain underwater for over an hour. Their extraordinary abilities enable them to reach the very deep waters of the ocean, where they capture giant squid and large fish. Newborns have been observed in the Mediterranean in all seasons. Sperm whales can live to the age of eighty. Sperm whales have been seen only occasionally in the Sanctuary area.

Threats to the species

The biggest threat to the species comes from ship strikes. Sperm whales are also victims of by-catches from driftnet fishing.