European eels are critically endangered catadromous fish with complex life histories, whose welfare in commercial fishing and aquaculture is compromised by poor handling, stressful transport, and inhumane slaughter methods.
Eel welfare concerns span their entire commercial life cycle. Wild capture of glass eels and silver eels involves nets, traps, and electrofishing — all of which cause acute stress and potential physical injury. Live transport is common in the eel trade, with animals held at high densities for hours to days in water of poor quality; oxygen depletion during transport causes hypoxic distress. Traditional slaughter methods used in Europe and Asia — including gutting live eels, salt killing, or placing them in vinegar baths — cause prolonged distress before death. The pain response of eels during salt killing is well-documented; high sodium chloride concentrations cause intense mucus secretion and writhing behaviour over many minutes before death. Electrical stunning before slaughter dramatically reduces the period of conscious suffering and is technically feasible in commercial settings. The critically endangered status of wild eels means that welfare concerns intersect with conservation: every commercially exploited eel represents a significant fraction of a depleted population.