European and Japanese eels are increasingly farmed under intensive conditions that raise serious welfare concerns, compounded by significant knowledge gaps about eel sentience, stress responses, and humane slaughter methods.
Eel welfare sits at a difficult intersection: a species whose sentience and capacity for suffering remain incompletely characterised, yet which is farmed at massive scale under conditions that clearly cause physiological stress. The precautionary principle — that where we cannot rule out suffering we should act to minimise it — applies strongly here. Until validated humane slaughter methods are available and adopted across the industry, eels face the prospect of prolonged suffering at the point of death. Welfare researchers urgently need investment to close the knowledge gaps around eel pain processing, stress physiology, and effective stunning methods. Consumer and regulatory pressure can accelerate this research and incentivise adoption of higher welfare practices.