Sperm whales restructure their click "language" around shipping noise, not just get louder

Project CETI researchers found that sperm whales off Dominica don't just raise their volume near ships — they compress click tempo and shift coda types, altering the combinatorial structure of their communication. After four years and 1,000-plus recorded codas, researchers could predict ship presence from vocalizations alone. The study, published in Ecological Informatics, raises a policy question: decibel-based noise rules may miss functional impacts on whale communication. Speed limits and vessel rerouting could matter as much as quieter ships.