Sperm whales have the largest brains on Earth and live in complex matriarchal societies. Noise pollution, ship strikes, and plastic ingestion threaten these extraordinary animals.
Sperm whales are among the most cognitively sophisticated animals on Earth. Their large brains support complex social bonds, cultural transmission, and potentially rich inner lives. Noise pollution — particularly military sonar and industrial shipping noise — causes disorientation and may trigger the panicked ascent from depth that causes decompression injury. Plastic ingestion impairs digestion; large quantities of plastic have been found in stranded whales that had died of starvation despite full stomachs. Entanglement in deep-sea fishing gear causes drowning. The loss of matriarchal knowledge-holders through mortality disrupts cultural transmission across generations — a form of welfare harm that operates at the social and cultural level unique to cognitively advanced species.