Sport fishing is a growing segment in the fishing sector in Brazil. It is, however, an activity that depends upon young shrimp and fish offer to supply live bait demand, its extraction might result on overfishing and compromise natural stock. The intensive cultivation in water recirculation system is a worldwide trend for aquaculture, which, in addition to increasing productivity, minimizes the impact of effluent emission on the environment, reinforcing sustainability. This study analyzed the economic viability of establishing farms for the cultivation of lambari (Deutorodon iguape) in water recirculation system to meet the market demand of sport fishing for live baits. Twelve fiberglass tanks with a volume of 1500 L and a unit area of 1.32 m2 (production units - PU) were installed in a total area of 130m2. There were also six fiberglass tanks of 2,000 L capacity each, filled with water and 600 kg of clamshells acting as biological filter. Three production cycles were performed, each lasting 60 days. In each cycle 10,800 D. iguape fingerlings were added, acquired from local fish farming, at a 600 fish m-3 density, totalizing 900 fish per PU, with medium size and weight of 10 ± 1.2 mm e 1.1 ± 0.29 g. We used the following indicators: modified internal rate of return (MIRR), net present value (NPV), annualized net present value (ANPV) and payback period (PP). The best scenario, with 90% survival rate and unitary selling prices of US$ 0.30, showed MIRR 33.19%, NPV (10%) US$ 42,174.03, ANPV (10%) US$ 6,863.63 and PP 0.9 years, demonstrating be interesting the production of live baits in the conditions proposed in this study.

This study aimed to verify the economic feasibility of a small-scale aquaponics system for the production of lambari (Astyanax lacustris) for ornamental purposes or as live bait, together with lettuce (Lactuca sativa) for human consumption. The hypothesis is that this activity would be a profitable option that provides increased income to small producers. The investment needed to implement the project was US$ 40,118.06. Under these conditions, the Internal Rate of Return (IRR) values varied from 13.2%, for the lowest prices (US$ 0.15 and US$ 0.34 for lambari and lettuce, respectively), to 41.5%, in the best scenario, with a price of US$ 0.14 for lambari and US$ 0.44 for lettuce. For the live bait market, only for the lowest selling price (US$ 0.15 for lambari and US$ 0.34 and US$ 0.39 for lettuce), the IRR was below the minimum attractive rate of return which was stipulated to be 12% here in. The return on investment will be achieved between 3.38 and 6.40 years (Ornamental fish market), and between 4.29 and 8.30 years (Live bait market), depending on the sales value used. Under the proposed conditions and scenarios, the aquaponic system evaluated herein presents a moderate risk in terms of economic viability.

This study evaluated the economic feasibility of scallop monoculture (Nodipecten nodosus) in six 100-meter longlines, monoculture of cobia (Rachycentron canadum) in twelve 565.5 m³ net cages, and the integrated multitrophic aquaculture system (IMTA) with both species, in four longlines and six net cages of the same dimensions, in an area of 5,000 m², on the southeastern coast of Brazil. This study aimed to determine whether this approach could provide greater profitability and resilience than traditional monocultures. Investments, operating costs, and profitability were estimated for the three production systems according to the variation in survival, productivity, and market prices. The financial indicators showed positive values for the three systems evaluated. There was a reduction of US$ 1.88 per dozen scallops from scallop monoculture to IMTA and US$ 0.22 per kg of cobia from cobia monoculture to IMTA. However, comparatively, scallop monoculture had the worst results. For this system, although the IRR (35.03%) and MIRR (19.37%) are above the MRA (12%), the NPV, ANPV, and PP (US$ 69,785.07, US$ 12,350.85 and 3.71 years, respectively), had lower economic attractiveness when compared to the other two systems evaluated. Between cobia monoculture and IMTA, there is a certain proximity of results. The IMTA system showed a slight advantage in terms of the highest market prices. The diversification of production is an interesting option even with the greater associated investment, which can favor economic returns and mitigate the risks of small-scale systems dedicated to monocultures.