Harbor porpoises are among the smallest cetaceans and face serious threats from fishing gear entanglement and pollution in coastal waters.
Harbor porpoises trapped in fishing gear drown in a matter of minutes - a rapid but extremely distressing death as highly air-breathing mammals cannot escape entanglement. Porpoises are one of the most susceptible cetaceans to gillnet bycatch due to their preference for the same coastal habitats where gillnets are most commonly deployed. Pinger technology represents a genuinely effective, economical welfare and conservation intervention - reducing bycatch by 50-90% in some studies. Pollution with persistent organic compounds causes immune suppression, reproductive failure, and potentially cancer in affected individuals. The cumulative stressors affecting harbor porpoise welfare in increasingly busy coastal seas requires a multi-threat response.