Commercial Fishing Bycatch: The Hidden Welfare Cost of Seafood

Bycatch — the unintended capture of non-target species — kills billions of fish, sea turtles, dolphins, and seabirds annually. Understanding this welfare crisis is essential to responsible seafood choices.

Key Facts

Global bycatch is estimated at 38 million tonnes annually — roughly 40% of all marine catch
Sea turtles, dolphins, sharks, and seabirds are among the most welfare-significant bycatch species
Shrimp trawling has among the highest bycatch ratios — for every kilogram of shrimp, up to 10kg of bycatch may be discarded
Longline fisheries kill an estimated 300,000 seabirds annually including albatrosses and petrels
Circle hooks, turtle excluder devices, and acoustic pingers can reduce bycatch of sensitive species by up to 90%

Welfare Considerations

Bycatch animals experience a range of welfare harms depending on capture method and species. Fish caught in trawl nets experience decompression injuries, crushing, asphyxiation, and prolonged stress before death. Sea turtles and marine mammals may drown in nets or suffer severe injuries from hooks. Seabirds caught on longlines experience drowning and hook injuries. Even when bycatch animals are returned to the sea alive, survival rates are often low due to injuries and stress. The scale of the problem — tens of billions of individual animals annually — makes bycatch one of the largest sources of animal suffering caused by human activity. Mitigation technologies exist but adoption is uneven and often inadequately enforced.

What You Can Do

Choose seafood certified by the Marine Stewardship Council (MSC) which includes bycatch criteria
Use seafood guides from Seafood Watch or Good Fish Guide to identify lower-bycatch options
Avoid shrimp from countries with poor bycatch regulations unless certified sustainable
Support campaigns for mandatory adoption of turtle excluder devices and seabird-safe longline practices
Reduce overall seafood consumption to decrease demand driving high-bycatch fisheries