European and Japanese eels are increasingly farmed due to wild stock collapse, and their welfare in recirculating systems requires understanding of their unique physiology and behavioral needs.
Farmed eel welfare involves a dual ethical problem: the welfare of individual farmed animals and the conservation harm of relying on wild-caught juveniles from Critically Endangered wild populations. European eels cannot currently be bred in captivity, meaning every farmed eel began as a wild-caught glass eel that was removed from the wild population. The welfare of farmed eels is affected by high stocking densities, artificial light cycles that may interfere with their nocturnal activity patterns, and the frustration of migration drive in silver eels approaching spawning readiness. The most welfare-positive approach to eel consumption is avoiding it entirely until wild populations recover and captive breeding becomes viable, reducing both individual welfare harm and conservation damage.