Atlantic halibut are among the most challenging flatfish to farm, with welfare considerations around their sedentary nature, cannibalism, and slaughter practices in a growing but small industry.
Farmed Atlantic halibut represent an interesting aquaculture welfare case where the species biology creates both challenges and opportunities for welfare improvement. Their flatfish sedentary behavior means that spatial requirements are somewhat different from pelagic species — dense stocking in terms of kg/m3 does not necessarily cause the same movement restriction as for salmon or trout. However, cannibalism in juvenile phases requires frequent size-grading operations that impose handling stress. Substrate provision — sand or gravel on tank bottoms — allows expression of natural camouflage behavior that is otherwise frustrated in bare tanks, reducing stress indicators. Slaughter method standards are less developed for halibut than for salmon, and live-chilling remains common. The small scale of the industry provides an opportunity to establish strong welfare standards early before the sector grows to the scale where reform becomes economically disruptive.