Sperm whales are the largest toothed predators and live in deep social matrilineal groups. They face threats from plastic ingestion, noise, and historical overhunting.
Plastic ingestion can cause internal blockages, starvation, and perforation. Noise from seismic surveys and military sonar may disorient animals and prevent feeding. Entanglement in deep-set longlines is documented. Stranded sperm whales may suffocate under their own weight. Long social memories mean loss of individuals has consequences beyond the individual - matriarchs hold ecological and social knowledge.