European and Japanese eels are farmed in intensive systems with welfare challenges compounded by the species' complex biology and wild population collapse.
Eel welfare in aquaculture is particularly complex because the entire farmed population starts as wild-caught juveniles — there is no captive breeding program. Wild glass eels are captured and transferred to intensive farming systems where they are reared to market size. High stocking density, poor water quality management, and transport conditions create significant welfare harm. The collapse of wild eel populations adds an urgent conservation dimension to welfare concerns.