The European eel is critically endangered — population has declined 95% since the 1970s. Wild eels caught for aquaculture, and the methods used to keep and slaughter them, raise significant welfare concerns at a time when the species can ill afford any additional mortality.
European eel welfare in aquaculture faces two interlocking problems. First, all farmed eels start as wild-caught glass eels — each farmed eel represents a wild individual removed from a critically endangered population, which is both an ecological and a welfare concern for the species as a whole. Second, eels are physiologically difficult to kill humanely: they tolerate low oxygen, survive stunning and continue moving after decapitation. Water temperature reduction combined with electrical stunning followed by immediate decapitation is considered best practice, but compliance in commercial settings is inconsistent. The continued use of live eel transport and sale in East Asian markets creates additional welfare concerns. CITES Appendix II listing has restricted but not eliminated glass eel trade.