Stock Assessment and Conservation of Fisheries Resources in the Bay of Bengal: Policy Implications for Sustainable Development of the Blue Economy

The marine area of the Bay of Bengal (BoB) of Bangladesh is one of the world’s 64 Large Marine Ecosystems. The entire shelf area of Bangladesh (up to 200 m depth contour) covers about 70,000 km2. The BoB is very rich in fish and shrimp species biodiversity. Around 511 marine species together with shrimps are available within Bangladeshi territories of which 100 important species of 20 fish families are highly commercial, contributing about 82-87% of the total demersal exploitation in the country. The potential of the coastal fisheries sector has not been rationally harvested. Rather the resources have been over-exploited, and as a result, the stocks of several important fish declined. Climate change also affected fishery production in marine ecosystems. Throughout and subsequent to the Rio +20 process there has been a growing appreciation that the world’s Oceans and Seas require more coordinated action. Healthy oceans are essential for global food security, livelihoods, and economic growth to address the world’s big challenge of the 21st century to feed 9 billion people by 2050 in the face of climate change. The Government of Bangladesh also prioritized investment for the development of the blue economy for food security and poverty reduction. The present study was conducted to assess the stock of commercial fish species of the Bay of Bengal (BoB) to ensure maximum sustainable yield for assisting the livelihood of the highest number of fishers for sustainable management of marine fisheries and identify the major man-made and climatic threats/factors to fisheries resources in the BoB using both primary and secondary data. The study revealed that the country has a total of 740 marine fish species in the BOB. Growth parameters, size at sexual maturity, and optimum catchable length of 15 commercially important marine fishes were estimated of which 4 species had balanced exploitation, 3 species were over-exploited, and the rest 8 are under-exploited. The analysis of gene diversities indicated that the studied fishes have experienced population expansion after a period of low effective population size, except for two species, M. cordyla and L. calcarifer for which the gene diversities were also low. This result implies that these two fish species of Bangladesh have experienced a recent bottleneck. Immediate conservation measures should be taken for these two species. Fishing with destructive fishing gears in seas was found to be a man-made cause or threat for declining of commercially important marine fishes in the BoB. The results of the study contributed to the management and policy strategies of Marine Fisheries to develop the Blue Economy. The government needs to formulate a policy for sustainable harvest and conservation of fisheries in the Bay of Bengal and some key policy actions are suggested for a healthy eco-system and sustainable management of marine fisheries resources.

Keywords:Blue economy; Marine eco-system; Stock assessment; Sustainable fisheries resources management; Policy actions