Species: Physeter macrocephalus Linnaeus, 1758
It is the largest existing toothed whale, characterized by a huge box-like head, with a low dorsal fin and small flippers. Males are larger than females: 18 m long, weighting 50 tonnes maximum the former, 12 m and 20 tonnes the latter.
The skin is dark-grey to black, while the body surface on the back is wrinkly. Sperm whales swim slowly if undisturbed, diving to find food up to around 1,000 m for about 45 minutes, feeding mainly on mesopelagic squids.
They have distinctive bushy, forward-angled blow, lifting their flukes high out of the water as they begin a feeding dive. Males and females adults form separate schools that join together during the breeding season. It can reach 80 years of age.
Sightings of sperm whales are increasing in the northern part of the Pelagos Sanctuary, while off North-eastern Sardinia, depending on the year, you can meet both solitary males or social units of female and their offspring. The main threat to this species is represented by collisions with vessels; by-catches in driftnets may also occur.
The sperm whale is classified as Endangered (EN) on the IUCN Red List 2012 for Mediterranean subpopulation and is listed under Appendix I of CITES