Herring and other pelagic fish are caught in enormous volumes by purse seine and trawl, with welfare considerations for these schooling fish during capture and killing.
Pelagic fisheries welfare for herring and related species involves the largest numbers of individual fish of any fishery type. The capture process involves massive crowding stress during net encirclement, followed by hauling that causes pressure changes, physical damage, and asphyxiation. Industrial-scale pumping of fish from nets to vessels causes additional mechanical trauma. The enormous volume of fish involved means that even small improvements in killing methods at the point of harvest could benefit billions of individual fish. Rapid chilling using refrigerated seawater after pumping provides some welfare benefit compared to slower death. The primary welfare challenge is the scale of industrial pelagic fishing operations that makes individual animal welfare consideration practically very difficult.