Wild dolphins are highly intelligent social mammals whose welfare is threatened by bycatch, pollution, boat disturbance, and climate impacts on prey availability, raising significant ethical questions about marine welfare.
Wild dolphin welfare encompasses both acute harms from anthropogenic threats and chronic welfare impacts from habitat degradation. Bycatch causes drowning — a terrifying and prolonged death for air-breathing social mammals that may call for group members during their distress. Noise pollution from sonar has been linked to mass strandings where dolphins suffer severe decompression sickness from panic-diving responses to military sonar. Chemical pollution accumulates in blubber and impairs immune function, causing susceptibility to disease. The cognitive and social complexity of dolphins means they experience social disruption — the death of pod members, separation of mothers and calves by fishing activities — in ways that engage higher-order psychological capacities. The aggregated welfare impact of multiple simultaneous anthropogenic stressors on dolphin populations is substantial.