APPLICATION OF CMSY TO ESTIMATE BIOLOGICAL REFERENCE POINTS OF BOMBAY DUCK (Harpadon neherus) FROM THE BAY OF BENGAL, BANGLADESH

CMSY method was used to calculate Biological Reference Points (BRPs) of Harpadon nehereus using seventeen years (2001)(2002)(2003)(2004)(2005)(2006)(2007)(2008)(2009)(2010)(2011)(2012)(2013)(2014)(2015)(2016)(2017) of catch data from the Bay of Bengal (BOB), Bangladesh. CMSY requires only catch and resilience data with quantitative stock status information. Also, a Bayesian statespace implementation of the Schaefer production Model (BSM) was used. The lowest Maximum Sustainable Yield (MSY) was provided by BSM (60600 t) that was smaller than last year's catch (82767 t in 2017). The fishing mortality (F) was estimated to be 0.22 and 0.23 for CMSY and BSM, respectively. The intrinsic population growth rate (r) was lower according to BSM (0.37) than the CMSY (0.57). Calculated B/BMSY was 1.13 and F/FMSY was 1.21 from the BSM model for the last data year. Estimated BRPs directed the overfishing status that may lead the H. nehereus fishery to be unsustainable. Therefore, proper management strategies are required to ensure the sustainability of H. nehereus in the BOB, Bangladesh.