Shark populations have declined by over 70% globally since 1970 due to overfishing, with significant welfare implications for captured individuals dying as target catch and bycatch.
Sharks caught in fishing gear and left on lines experience progressive stress, exhaustion, and suffocation as they are unable to ram-ventilate their gills. Pelagic species like makos caught on longlines may struggle for hours before dying or being hauled aboard. Finned sharks dropped back into the water alive sink to the bottom unable to swim, dying from suffocation over hours. The welfare scale of shark fisheries mortality is enormous — hundreds of millions of individual welfare events annually in a group of animals with complex neural organization and behavioral repertoires.