European and Japanese eel aquaculture relies on wild-caught glass eels and faces significant welfare challenges including stocking density, disease, and slaughter practices.
Farmed eel welfare sits at the intersection of individual welfare concern and conservation crisis. The aquaculture industry depends entirely on removing wild glass eels from rivers — eels that could otherwise replenish the severely depleted wild population. Individual welfare in farms is compromised by high stocking densities, disease burden, and slaughter practices that vary enormously in humaneness. Eels are nociceptive animals capable of detecting and responding to painful stimuli, and slaughter by asphyxia or being processed alive causes prolonged suffering. The welfare case for both better farm conditions and more humane slaughter is supported by growing evidence of eel sentience.