Yellowtail — including Japanese amberjack and California yellowtail — are high-value farmed fish whose welfare in net pen systems is an emerging concern.
Yellowtail welfare in aquaculture is poorly studied relative to salmon, but significant concerns exist. As active pelagic fish, yellowtail experience confinement stress in net pens — circular swimming and surface-breaking behavior indicate chronic frustration. High stocking densities cause fin injuries, aggression, and increased parasite burdens. Yellowtail are highly susceptible to ectoparasites like Caligus (sea lice), which cause skin damage and chronic irritation. Handling stress during grading and harvesting can be severe, as yellowtail are strong, fast fish prone to injury in nets. Starvation before slaughter — standard practice to clear the gut — causes prolonged hunger. Improving welfare requires lower stocking densities, improved parasite control, and humane slaughter methods.