Cage farming of Nile tilapia in African Great Lakes is growing rapidly as an affordable protein source. Welfare conditions in these systems present unique challenges distinct from tropical pond culture.
Tilapia in African Great Lake cage systems face welfare challenges from both chronic and acute sources. Seasonal oxygen depletion events cause mass mortality events that represent welfare crises for affected cages. Chronic overcrowding reduces individual fish access to optimal feeding opportunities and creates persistent social stress. Harvest practices that involve progressive crowding as the net is drawn in followed by asphyxiation in air or ice impose acute welfare costs on fish that could be killed more humanely with minimal additional effort. The development of improved welfare practices must be aligned with the economic realities and social context of the communities that depend on this industry.