The sperm whale (Physeter macrocephalus) is the world's largest toothed predator and the deepest-diving mammal on Earth, capable of descending to 3,000 metres. Despite recovering from commercial whaling, ship strikes and ocean noise continue to cause welfare harm to this iconic species.
Sperm whales struck by ships suffer catastrophic injuries: propeller lacerations sever flukes, fracture spines, and cause internal organ damage. Whales that survive initial strikes may be incapacitated and unable to dive for food, dying of starvation over weeks. Acoustic pollution from shipping disrupts the complex click-based communication through which sperm whale matrilineal groups maintain social bonds — a welfare impact on cognitively and socially complex animals. Stranded sperm whales found with stomachs full of plastic debris — bags, fishing nets, and packaging — suffer malnutrition and gastrointestinal distress before death.