European and Japanese eels are farmed in large numbers for food markets in Asia and Europe. Both farmed and wild eel populations face significant welfare concerns that receive minimal public attention.
Farmed eel welfare suffers from compounding problems: extremely high stocking densities, chronic aggression-induced injury, inadequate environmental complexity, and slaughter without stunning. The dependence of eel farming on wild-caught juveniles also raises conservation concerns that interact with welfare — the capture and transport of glass eels for farming involves high mortality and stress at a vulnerable life stage. Eels are physiologically resilient, which has historically led to assumptions that they are insensitive, but resilience and insensitivity are not the same thing. The welfare case for improved eel farming standards — lower densities, enrichment, stunning before slaughter — is as strong as for any other farmed fish species.