Hilsa (Tenualosa ilisha) is an anadromous fish, distributed throughout coastal regions from the Mekong estuary of Vietnam to the Persian Gulf (Pillay and Rosa, 1963). The Bay of Bengal is the major producing region for this species, from where it migrates to the rivers Padma, Meghna and its tributaries for breeding and nursing (Rahman, 2006). Among other species of the genus Hilsa and Tenualosa, this species ilisha makes up 99 per cent of total hilsa catches in the Bay of Bengal region (Rahman et al., 2012a). It was the most dominant single species in the Ganges river system in the pre-Farakka period until the middle of the 1970s. The availability of hilsa is now mostly centred in the Meghna estuary, the Padma River and some coastal areas of Bangladesh. It is commercially exploited in India and Myanmar as well (Milton, 2010). About 60 per cent of the total catch of hilsa within the Bay of Bengal region is harvested by Bangladesh, and the remainder caught by Myanmar and India. Hilsa constitutes 11 per cent of the total 2.9 million metric tonnes fish production of Bangladesh (Rahman et al., 2012a). Hilsa alone makes up 1.0 per cent of the GDP and contributes a considerable amount to foreign exchange earnings. About 287,000 fishermen are directly dependent on the hilsa fishery for their livelihood and about 2.0–2.5 million people are involved in different activities throughout the value chain, such as in transportation, marketing, processing and other post-harvest activities (ibid.). It is the favourite fish of the people of Bangladesh and West Bengal (in India) and considered as a fish of religious and cultural importance, and part of Bengali festivals. Hilsa has been recognized as the ‘National Fish’ of Bangladesh.