Anthropogenic noise from shipping, sonar, and seismic surveys disrupts cetacean communication, navigation, and foraging, causing welfare harm at individual and population levels.
Cetaceans that depend on sound for navigation, communication, and foraging are profoundly affected by anthropogenic noise. Whales displaced from feeding areas by shipping noise or sonar cannot compensate their energy requirements. Social species that can no longer communicate effectively across their range experience social isolation. In extreme cases — military sonar events — acoustic trauma causes physical damage to hearing and swim bladder organs, leading to the disorientation and mass strandings associated with naval exercises. The welfare harm is both acute in mass stranding events and chronic in the form of communication, foraging, and reproductive disruption across all affected populations. Shipping speed reductions, sonar restriction zones, and seismic survey timing restrictions all reduce this welfare burden.