Marine Animals

Harbor Porpoise Bycatch and Acoustic Deterrents

Harbor porpoises are killed in enormous numbers in gillnet fisheries but acoustic deterrents called pingers can reduce bycatch by over 90%.

Key Facts

Harbor porpoises are among the most commonly caught cetaceans as fisheries bycatch globally
EU regulations require pingers on gillnets in many fisheries following evidence of effectiveness
Pingers emit sounds that deter porpoises from approaching nets before entanglement
Implementation compliance remains poor with many vessels not using required pingers
The Baltic harbor porpoise subspecies has been reduced to under 500 individuals by bycatch

Welfare Considerations

Harbor porpoises entangled in gillnets drown within minutes due to their breath-holding limits. Pinger technology that prevents entanglement is proven, cheap, and widely available — making pinger non-compliance a preventable welfare harm. The critically endangered Baltic harbor porpoise faces extinction from bycatch with solutions readily available but inadequately enforced.

What You Can Do

Support strong enforcement of pinger requirements in fisheries managing harbor porpoise bycatch
Advocate for expansion of pinger requirements to all gillnet fisheries in porpoise habitat
Choose seafood from fisheries using comprehensive marine mammal bycatch reduction
Donate to harbor porpoise research and conservation organizations
Learn about the Baltic harbor porpoise crisis as an example of regulatory failure in wildlife protection