Common dolphins are killed in large numbers as bycatch in French and Spanish pair trawlers in the Bay of Biscay, causing one of Europe's worst marine mammal welfare crises.
Common dolphin bycatch causes intense welfare suffering. Dolphins that become entangled in trawl nets drown, a death involving struggling, air deprivation, and prolonged distress before loss of consciousness. Dolphins that survive entanglement but are injured may die slowly after escape. The scale of mortality — potentially tens of thousands per year across all Northeast Atlantic fisheries — represents one of the largest marine mammal welfare crises in European waters. The available technology to reduce bycatch, including pingers and modified fishing gear, exists but has not been mandated at the scale needed to address the problem. Political pressure from conservation organisations and citizens can drive the regulatory changes needed.