Growth and Predator-Prey Interaction of Asian Seabass, Lates calcarifer and Sabaki Tilapia, Oreochromis spilurus in Polyculture System Sambhu Chithambaran 1 Received: 15 March 2018 # Springer Nature Switzerland AG 2018 Abstract A study was conducted to assess the growth and predator-prey interaction of Asian seabass and Sabaki tilapia in polyculture ponds (0.1 ha) for a period of 180 days. Ponds stocked with tilapia (3000/0.1 ha) alone were considered as control, whereas ponds stocked with tilapia at 3000 + Seabass 600/0.1 ha were considered as Treatment 1 and the ponds stocked with tilapia at 5000 + Seabass 600/0.1 ha were designated as Treatment 2. Significant difference (p < 0.01) in growth and production was observed between control and treatments. Better feed conversion ratio was observed in Seabass compared to tilapia in control. In tilapia, gonad maturation was started in second month onward and the highest ovary development was recorded in 3–6 months of culture, whereas gonad development of Seabass was in rudimentary stage. A combination stock of tilapia at 5000 and Seabass at 600/ 0.1 ha brought 86% higher profit than the monoculture of tilapia. Polyculture of tilapia with Seabass is ideal to control the prolific breeding and population explosion of tilapia in culture ponds. Keywords Polyculture . Gut content analysis . Gonad maturation . Cost benefit analysis . O.spilurus . L. calcarifer Introduction Polyculture, the rearing of two or more aquatic species together in a pond is a production technique used to in- crease overall fish production and profits (Dupree and Huner 1984; Fortes and Genodepa 1997; Petersen et al. 2011). The multiplication and proliferation of tilapia in culture waters, their capability to reproduce quickly and their acceptance as forage by piscivores fishes have de- veloped interest in the use of Seabass to manage tilapia reproduction and propagation (Hossain et al. 1997). Study by Schramm and Zale (1985) showed that largemouth bass (Micropterus salmoides) show a preference for blue tilapia (Oreochromis aurea) over indigenous forage; this was dependent upon forage size and availability as well as vegetative cover. Swingle (1960, 1966) examined the abil- ity of largemouth bass and peacock bass to utilize tilapia spawned in tilapia production ponds. The addition of car- nivorous predators reduced the total number of tilapia (juveniles) while increasing the number of harvestable tilapia (Li and Mair 2003). Asian Seabass (or barramundi), Lates calcarifer, is a large predatory fish found in coastal, estuarine and fresh- water environments in the Indo-Pacific region and also considered as a species for coastal aquaculture practice (Petersen et al. 2011). Fortes ( 1985) revealed that Seabass-tilapia combination of 1:15 ratio showed promis- ing result, whereas Tesorero (1995) reported 1:20 as the optimum ratio of Seabass and tilapia in polyculture. Seabass is an excellent cultivable species in variable water salinities ranging from 0 to 30 ppt (James and Marichamy 1986; Kungvankij et al. 1986; Mukhopadhyay and Karmakar 1981). Seabass is carnivorous and therefore it can be used as an efficient predator for controlling tilapia progenies (Petersen et al. 2011). Considering the predatory character, ability of salinity tolerance and culture prospec- tive, a study was conducted to evaluate the growth and predator-prey interaction of Asian seabass for controlling tilapia progenies in polyculture ponds. Electronic supplementary material The online version of this article (https://doi.org/10.1007/s41208-018-0112-z) contains supplementary material, which is available to authorized users. * Sambhu Chithambaran sambhu@kau.edu.sa 1 Department of Marine Biology, Faculty of Marine Sciences, King Abdulaziz University, P O Box 80207, Jeddah, Kingdom of Saudi Arabia Thalassas: An International Journal of Marine Sciences https://doi.org/10.1007/s41208-018-0112-z