Bioeconomic model for the evaluation of a backyard aquaculture system for tilapia (Oreochromis niloticus)

Backyard aquaculture is gaining importance as a source of food and economic input for rural families in Mexico. The profitability of this system needs to be determined. Bioeconomic tools allow for making profit projections of any production system. A bioeconomic model composed of biological, production, and economic sub-models was developed to evaluate a low-cost backyard aquaculture system (BAS) appropriate for rural communities, considering theoretical productive parameters at certain environmental conditions. The BAS consisted of a 2800 L water reservoir stocked with 168 masculinized 1 g fingerlings of tilapia (Oreochromis niloticus) at 60 ind m(-3) density and aerated with two ventury-type submerged pumps of 0.046 hp at a rate of 1400 L h(-1) each. Two culture cycles of 25 weeks each were analysed. The initial investment was USD 1200 (USD 775 equipment + USD 425 operation cost yr(-1)). Results from the model indicate the production of 303 fishes of 614 g, equivalent to 186 kg yr(-1), considering 10% mortality. Selling at USD 3.62 kg(-1), net profits varied from USD 184 to 16 at 0 and 25% self-consumption. The payback period was three and four years at 0 and 10% self-consumption but was longer than five years at 25%. A response surface plot of profitability indicators (cost-benefit, net present value, and internal rate of return) was constructed at different self- consumption percentages, sale prices, and temperatures. In conclusion, BAS is a viable self-sustainable alternative for tilapia production at a low scale in rural areas of Mexico and other Latin American countries.