Industrial fishing methods cause enormous suffering to wild fish and other marine animals caught as bycatch.
Wild-caught fish welfare is almost entirely unregulated despite evidence that fish experience pain. Trawl nets cause crushing, barotrauma, and asphyxiation as fish are compressed by tons of catch. Asphyxiation in air on deck causes prolonged conscious distress. Discarding bycatch returns injured fish to the sea with poor survival prospects. The scale of global fishing means the aggregate suffering may be one of the largest welfare problems on Earth.