Rearing of carried over carp seed in pen enclosure in a closed floodplain wetland of Assam.

Abstract

Floodplain wetlands of India cover an area of over 3.54 lakh ha and constitute an important fishery resource in the states of Uttar Pradesh, Assam, West Bengal, Bihar and Manipur (Bhattacharjya, 2011). Assam has the largest area (1, 00,815 ha) under floodplain wetlands (locally called beels) in the north-eastern region of India ( Bhattacharjya et al., 2015a). These wetlands can produce 8 times more benefits than that of a paddy field of an equivalent area ( Jhingran, 1989), as they are rich in nutrient load with availability of wide range of fish food organisms. Pen aquaculture in the floodplain wetlands of Assam has proven to be economically viable with positive benefit-cost ratios ( Bhattacharjya, 2003Bhattacharjya, , 2011Katiha et al., 2005, Gorai et al., 2006aChandra, 2010;Bhattacharjya et al., 2015a). However, the benefit-cost ratios in the previous experiments and field trials ranged from 1.35-2.15.with an average of 1.74 for one crop ( Katiha et al., 2005). In a recent study, we demonstrated that rearing of carried over carp seed in a pen of 741 m 2 installed in Damal beel of Assam yielded a BCR of 1.8 ( Bhattacharjya et al., 2015a). In the present study, we observed an overall BCR of 2.52, which is far higher than the values reported in the past.