Harbor porpoises are among the most frequently bycaught marine mammals globally, with drowning in fishing nets causing tens of thousands of welfare-significant deaths annually.
Harbor porpoise bycatch welfare is one of the most significant but least visible marine animal welfare issues. Each bycaught porpoise drowns in the net — a process that takes minutes and involves conscious distress throughout. Acoustic deterrents have demonstrated consistent bycatch reduction effectiveness, and mandatory pinger deployment represents a welfare-positive intervention with strong evidence base. Compliance monitoring is the primary implementation challenge — pingers that are not maintained or deployed correctly have reduced effectiveness. Consumer pressure on seafood companies to require pinger compliance certification from their gillnet suppliers creates market incentives for compliance.