Evaluation of the Production Performance of Edible Oyster (Crassotrea Belcheri) and Efficacy as Extractive Species at Varied Densities in Land Based Integrated Multi-Tropic Aquaculture (Imta) System in Bangladesh

Abstract

In order to boost productivity based on mutual gain for the co-cultured species and enhanced ecosystem health, integrated multi-trophic aquaculture (IMTA) combines species from various trophic or nutritional levels in a single system. In Bangladesh's coastal regions, edible oysters, or Crassostrea belcheri, are widely available. Because it is a filter-feeder, it can be employed as an extractive species in IMTA to remove organic materials.  To gauge the impact of varying C. becheri stocking densities on the performance of seabass (Lates calcarifer) and sea lettuce (Ulva lactuca), as well as environmental remediation in an IMTA system, an experimental trial was carried out. Seabass (200.51 ± 0.05 g) and seaweed (500.36 ± 0.02 g) were placed in 750 L FRP circular tanks with 1.5 (T1) and 2 (T2) kg m-3 of oyster density, respectively, at 4 no. m-3 and 0.5 kg m-2. The same quantity of seabass and seaweed without oysters was found in control tanks. There were three duplicate tanks for each of the two treatments and the control. The fish were fed chopped tilapia at 5 % of biomass for the duration of the 180-day study. According to the results, T2 had the highest growth rates for seaweed (4245.12 ± 9.24 g) and seabass (527.19 ± 2.31 g) (P < 0.05) when compared to the control group (442.33 ± 1.89 g for seabass and 2452.12 ± 7.12 g for seaweed). Seaweed and seabass survival did not differ; however, T2 had the highest rates of both. According to this experiment, when stocked at a density of 2 kg m-3, the oyster C. belcheri can function as an efficient extractive species in the IMTA system. As a result, treatment T2 IMTA was more effective and had a positive environmental bioremediation impact

Keywords: Oyster, Koral, Green seaweed, Mariculture, IMTA