Small pelagic fish like mackerel and herring are caught in enormous quantities with minimal welfare consideration despite evidence for fish sentience.
Small pelagic fish are among the most numerous vertebrates killed by humans annually, yet they receive minimal welfare consideration. Crowding and oxygen depletion in nets before hauling causes intense physiological stress. Death by suffocation after extraction from the water is slow and distressing. The scale of catch makes individual welfare improvements enormously impactful if implemented: even marginal improvements in slaughter methods applied across hundreds of billions of fish annually represent a vast reduction in aggregate suffering.