Mud Crab Culture as an Adaptive Measure for the Climatically Stressed Coastal Fisher-Folks of Bangladesh

Abstract

The coastal belt of Bangladesh endowed with diverse resources bears a significant scope in ensuring the security of food and livelihood of the coastal poor people. But the coastal belt of Bangladesh is highly affected by the natural calamities and salinity intrusion which are occurred due to climate change. Considering the above situation the present study was developed to conduct on-farm adaptive research on crab fattening/culture in Barguna and Patuakhali districts as a livelihood option for the fisher folks including female from September 2010 to August 2012. In case of crab fattening the main target is gonad development of female crab and shell hardening of male crab rather than weight gain. To conduct the experiment 24 study sites were selected where six cages and six pens were set in each district. The size of each cage was 2 m × 1 m × 0.3 m (length × width × height) comprising of 50 cells. And the length, width and height of each cell were 0.2, 0.2 and 0.3 m respectively. One lean crab (>180 g) was stocked in each small cell of the cage. The area of the pen was 100 m2 (10 × 10 m) where crab (50–150 g) stocked at three different densities (3, 5 and 7/m2). Low valued small waste fishes and formulated pellet feed were fed. Raw feed was given as wet weight basis at the rate of 8–10 % of the total body weight twice a day. Suitable salinity (3–15 ppt) for crab fattening/culture was found during November to June survival and gonad maturation were found higher during the time. Gonad maturation of mud crab occurred over the year but higher was found from December to May. Economic analysis revealed that it is possible to earn net profit 1,313.83–1,4761.30 BDT per cycle (cage 10–20 days, pen 20–30 days) from crab fattening/culture in one cage (50 celled) and pen (100 m2) respectively. Recommendation can be made to conduct comprehensive crab culture extension program for building capacity and improving economic condition of the climatically stressed coastal community.