Flying Fish Bycatch: Incidental Mortality in Tuna Fisheries

Flying fish are remarkable ocean gliders that escape predators by launching from the water. They face significant bycatch mortality in the same surface-set gear used to target tuna and mahi-mahi.

Key Facts

Flying fish can glide for hundreds of metres above the water using their enlarged pectoral fins
They are attracted to floating objects and artificial fish aggregating devices (FADs) used in tuna fishing
FAD-associated purse seine fishing captures large quantities of flying fish as bycatch
Flying fish eggs are harvested commercially for tobiko — the roe used in sushi — primarily in the Pacific
Their eggs are attached to floating debris including plastic waste, linking them to ocean plastic pollution

Welfare Considerations

Flying fish bycatch in FAD-associated purse seine fisheries represents a welfare harm that is largely invisible in fisheries management because they are not a target species. FADs aggregate diverse marine life below them, and the purse seine sets that harvest tuna take large quantities of flying fish simultaneously. Their mortality in the net represents direct welfare harm. Tobiko harvesting removes large quantities of eggs from the ocean surface, impacting larval recruitment. Switching to non-FAD tuna fishing methods reduces flying fish bycatch significantly.

What You Can Do

Choose canned tuna certified as FAD-free to reduce flying fish bycatch
Support Marine Stewardship Council certification standards that penalise high FAD use
Reduce ocean plastic waste that attracts flying fish eggs and then captures them in FAD gear
Follow the growing literature on FAD fishing impacts on non-target species welfare