WWW.WAS.ORG • WORLD AQUACULTURE • MARCH 2014 49 TABLE 1. Variation of climatic parameters for 20 years in Maijdee, Noakhali. Parameters 1988 2008 Change Annual max temperature (°C) 30.4 30.7 0.2 Annual min temperature (°C) 21.8 21.9 0.2 Annual average temperature (°C) 25.9 25.7 -0.2 Length of winter (day <15 °C) 40 34 -6 First winter day (<18 °C) 26-Nov 18-Nov -8 Length of summer (day >35 °C) 17 39 22 First summer day (day >30 °C) 5-Feb 23-Feb 18 Annual precipitation (mm) 3130 3020 -110 (4%) Length of rainy season (day >10 mm) 78 77 -1 First rainy day (>10 mm) 13-May 15-May 2 TABLE 2. Fishes with stocking density, production and market price in the waterlogged area of Begumgonj, Noakhali. Local Name Scientific name Stocked fish Stocking density Production Price) Total price (Indi./Decimal) (Kg) (Tk/Kg (Tk) Tilapia Oreochromis niloticus 1500 ~2 90 68.0 6,120 Grass carp Ctenopharyngodon idella 5000 3 180 49.0 8,820 Common carp Cyprinus carpio 2000 1 154 67.5 10,395 Rui Labeo rohita 5000 4 432 85.5 36,936 Mrigal Cirrhinus mrigala 3000 2 428 73.0 31,244 Catla Catla catla 5500 5 170 76.0 12,920 Shorputi Puntius sarana 5000 5 110 61.0 6,710 Bighead Hypophthalmichthys nobilis 3000 3 206 46.0 9,476 Golda Macrobrachium rosenbergii 1000 <1 25 190.0 4,750 SIS --- --- 1,055 42.0 44,404 Total 31000 26~27 2,850 171,775 Climatic Characteristics Data from the meteorological station at Maijdee (~3 km from the project site) showed the trend in seasonal changes over the past 20 years (1988-2008, Table 1). Even small changes in water temperature are expected to exert strong pressure on fish ecology (WWF 2005). An apparent warming and trend is seen, similar to expectations for global temperature change (IPCC 2007). About 80-90 percent of the annual rainfall is confined to the monsoon months (April-October, Fig. 3) although the trend is towards drier conditions. Farming System and Production Rainwater gradually accumulated and was stored in the selected hator during the middle of June. The water depth reached 80-100 cm in early July, a depth suitable for stocking fry. About 310,000 fry were stocked with 26-27 individual/decimal considering the different productivity niche of the pond ecosystem (CONTINUED ON PAGE 50) TABLE 3. Economic analysis of community-based aquaculture in a 4.5-ha hator at Begumgonj, Noakhali. Variable Amount (Tk.) Total (Tk.) Cost Pond lease 9900 Feed 10000 Fingerlings 30375 Operational 53000 Selling commission 13742 117,017 Revenue 171,775 Profit 54,758 ROI (%) 45
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