Sperm whales display two predominant types of behaviour: foraging and socialising. Adult males typically forage alone, whereas family units consisting of females, calves, and young males usually forage together, often spreading over distances of one kilometre or more. When resting or socialising at or near the surface, their behaviour can vary considerably. They may remain very quiet and still, or become more active, emitting vocalisations, rolling, and making physical contact with one another. Other surface behaviours include breaching and lobtailing (tail slapping).

A behaviour that appears to be unique to sperm whales is known as “drift diving.” During this behaviour, whales remain passive and upright in the water column, either with their heads pointing upward or downward, just below the surface. This posture is believed to represent a resting or sleeping state.

Sperm whales can live for up to 77 years, reaching sexual maturity between 9 and 21 years of age, depending on the sex. Mating can occur throughout most of the year, and the gestation period lasts approximately 14–16 months. Calves measure around four metres in length at birth, and weaning generally occurs after a minimum of two years. Females within a social group cooperatively care for the young, often alternating their dives so that some individuals remain at the surface to “babysit” the calves.

In the Mediterranean Sea, one of the most significant threats to sperm whales is entanglement in high-seas driftnets used for swordfish and tuna fisheries, which has caused considerable and potentially unsustainable mortality since the mid-1980s. Additional threats include vessel collisions, underwater noise pollution, ingestion of plastic debris, and the broader impacts of climate change.