Common eiders are among the most vulnerable seabirds to oil spill impacts in the North Sea, with their diving behaviour and dense winter aggregations creating exceptional risk.
Oil spills represent one of the most acute welfare threats to eiders. Oiling destroys feather waterproofing, causing rapid heat loss and hypothermia. Affected birds ingest oil during preening, causing internal organ damage, immune suppression, and reproductive harm. Even sublethal oiling significantly reduces welfare and survival. Prevention through stricter shipping regulations, rapid spill response, and wildlife rehabilitation capacity are all critical welfare safeguards. Rehabilitating oiled eiders is labour-intensive and success rates are modest.