Lake cage culture of tilapia is widely practiced in Africa and Southeast Asia. Welfare in cage systems depends on water quality management and stocking density control.
Tilapia welfare in lake cage systems is primarily determined by water quality, which is largely outside the direct control of individual farmers when driven by lake-wide eutrophication. Seasonal oxygen depletion events cause acute suffering before mass mortality. Cage placement at appropriate depth away from anoxic layers reduces risk. Individual stocking density management within cages is controllable and should target densities below chronic stress thresholds. Harvest improvements including rapid slaughter after minimal crowding reduce terminal welfare compromise.