WWW.WAS.ORG • WORLD AQUACULTURE • JUNE 2015 13 Inland Culture The Pacific whiteleg shrimp is a euryhaline species, able to tolerate a wide range of salinity. Low-salinity culture of Pacific whiteleg shrimp in abandoned tilapia ponds or in saline soil has become a viable and profitable alternative in some parts of northeast Brazil (Fig. 6). Culture water in these sites is usually oligohaline, with 0.5-0.6 g/L salinity, which is unsuitable for use in agriculture or other purposes. Inland shrimp farming has gone through a rapid expansion of culture area because land is less expensive than in coastal areas and environmental license permits are easier to obtain. To achieve adequate shrimp survival and growth under these conditions, shrimp must undergo an acclimation process before pond stocking. In the past, this process was carried out by farmers, imposing a greater risk in production. Today, qualified hatcheries and acclimation centers near production sites deliver acclimated PLs to meet the salinity requirements of individual farms. Tilapia Aquaculture Intensive culture in floating cages is the most popular farming system for tilapia in northeast Brazil. Compared to earthen pond culture, cages are easy to manufacture and manage, and require smaller investments. Cages vary in volume from 6 to as much as 350 m3 (Fig. 7). Tilapia are usually reared in this system from fry to a market size of 0.8 to 1.2 kg in 6 to 7 months, with yields from 60 to 100 kg/m3 per crop. In this type of cage aquaculture, there has been three major developments in northeast Brazil: 1) a shift from small-volume (CONTINUED ON PAGE 14) FIGURE 5. Privately owned shrimp hatcheries have played a key role in developing IMNV-resistant post-larvae. Shrimp hatcheries of Potiporã Aquacultura (A) and Celm Aquicultura (B) in the States of Rio Grande do Norte and Ceará, respectively. A. B. FIGURE 6. Center for acclimation of shrimp post-larvae to inland water with grow-out ponds in the back in Jaguaruana, Ceará state. Photo: Jeroen Vontilburg. FIGURE 7. Typical tilapia cage farms in northeast Brazil. Tilapia can be fed from boats (A) or walkways (B). Photos: Alberto Nunes. A. B.
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