Harbor Porpoise Welfare and Bycatch

Harbor porpoises are the most common cetacean in North Atlantic and North Pacific coastal waters, but bycatch in fishing gear causes tens of thousands of deaths annually.

Key Facts

Harbor porpoises are among the smallest cetaceans, reaching only 1.4-1.9 m in length
An estimated 6,000-10,000 are killed annually as bycatch in gillnets in the North Sea alone
They have one of the highest metabolic rates of any cetacean and must feed nearly continuously
Porpoises rely heavily on echolocation — noise pollution from shipping disrupts foraging
Acoustic deterrents called pingers have reduced bycatch by up to 90% in some fisheries

Welfare Considerations

Harbor porpoises represent one of the most numerically significant cetacean bycatch problems globally. Death in gillnets involves entanglement and drowning — a process that can take several minutes and involves acute panic, oxygen deprivation, and struggling. Even where population-level impacts are considered sustainable, the individual suffering involved is substantial at tens of thousands of animals per year. Acoustic pingers that deter porpoises from net areas have proven highly effective in scientific trials but adoption remains patchy due to cost and enforcement challenges. Noise pollution from recreational boating, shipping, and offshore construction also affects foraging efficiency and causes physiological stress responses measurable in stranded animals.

What You Can Do

Support mandatory pinger use in all gillnet fisheries operating in porpoise habitat
Choose seafood certified by the Marine Stewardship Council with low bycatch ratings
Advocate for reduced shipping noise in coastal marine protected areas