SON bi‐annual environment monitoring technical report for the cage culture site at Bugungu, northern Lake Victoria, June 2012

Source of the Nile Fish farm (SON) is located at Bugungu area in Napoleon Gulf, northern Lake Victoria. The proprietors of the farm requested NaFIRRI to provide technical assistance to undertake regular environment monitoring of the cage site as is mandatory under the NEMA conditions. NAFIRRI agreed to undertake regular environment surveys in the cage area covering selected physical‐chemical factors i.e. water column depth, water transparency, water column temperature, dissolved oxygen, pH, conductivity, redox potential and turbidity; nutrient status, algal and invertebrate communities (micro‐invertebrates/zooplankton and macro‐invertebrates/macro‐benthos) as well as fish community. The first year‐round quarterly surveys were completed for the year 2011. It was decided by SON management to change the frequency of the monitoring surveys to biannual starting in the year 2012 and the first such survey, which is the subject of this report, was undertaken in June 2012. Results/observations made are presented in this technical report along with a scientific interpretation and discussion of the results with reference to possible impacts of the cage facilities to the water environment and aquatic biota. SON

Feasibility of bi-culture of mud crab (Scylla serrata) and shrimp (Penaeus monodon)

A study on the feasibility of bi-culture of mud crab (Scylla serrata) and shrimp (Penaeus monodon) in brackishwater earthen ponds (0.1 ha each) was carried out for a period of five months (March-August). Nursed shrimp juvenile (ABL:· 3.36±0.23 em and ABW: 0.26±0.04 g) and crab juvenile (ACL: 2.61±0.22 cm, ACW: 4.63±0.11 cm and ABW: 43±2.64 g) were stocked following the experimental design of shrimp 2/m2 (Treatment-1), shrimp 2/m2 and mud crab l/m2 (Treatment-2) and shrimp 2/m2 and mud crab 0.5/m2 (Treatment-3). Crabs were fed with chopped trash tilapia @ 10~5%, while shrimp were fed with Saudi-Bangla shrimp feed @ 3~5% of biomass twice daily. Significantly (p<0.05) higher specific growth rate (SGR) of shrimp and mud crab was 1.86% (g/day) in T2 and 0.83% (g/day) in T3, respectively. The survival of shrimp and mud crab also varied significantly (p<0.05) with a higher mean value of74.63% in Tl and 51.04% in T3, respectively. The production of shrimp (424.09 kg/ha) was significantly (p<0.05) higher in Tl and that of mud crab (568.80 kg/ha) in T2. Significantly (p<0.05) highest total production of 871.29 kg!ha was in T2 followed by 708.52 kg/ha in T3 and 424.09 kg/ha in Tl. The results indicate that mud crab can be cultured at a stocking rate of 1/m2 together with shrimp at 2/m2 •

First bi-lateral consultation meeting on Gulf of Mannar ecosystem, Rameshwaram, India, 5-6 September, 2011

Status papers on resources, livelihoods and ecosystem approach to fisheries in the Gulf of Mannar(GoM) were presented.Five priority initiatives were agreed: collaborative effort in conservation and management of charismatic species (e.g. dugong),capacity building and training,education and awareness building, strengthening of data collection and sharing of information.