Fish are the most numerous vertebrates killed for food globally, yet they receive the least welfare protection at slaughter, with most farmed and wild-caught fish killed without any stunning or humane killing method.
Fish welfare at slaughter is one of the largest and most neglected welfare issues by scale. The weight of evidence supports fish sentience and capacity for pain, yet virtually all legal frameworks that require humane slaughter of terrestrial livestock exclude fish entirely. Asphyxiation — the most common method, simply removing fish from water — results in minutes of conscious suffocation. Live CO2 stunning causes prolonged distress before insensibility. Rapid and effective stunning methods exist and are commercially viable in aquaculture settings, making the ongoing use of inhumane slaughter methods primarily a matter of regulatory neglect rather than technical impossibility.