Population dynamics of Bombay duck <i style="">Harpadontidae nehereus</i> (Ham. 1822) (Teleostomi / Harpadontidae) from Mumbai waters, India

Abstract

Growth parameters were estimated for <i style="">H. nehereus</i> are <img src='http://www.niscair.res.in/jinfo/L-infinity.gif' border=0> =434 mm, K= 0.81 / yr and t_o= 0.0406 yr. Total, natural and fishing mortality were estimated as 4.33, 1.30, and 3.03 respectively. The M/K ratio was found to be 1.60. Length at first capture was found as at the place of found 210 mm. Present exploitation ratio (E) was calculated as 0.70. According to knife edge selection, the optimum E should be 0.66 at which at least 20% of virgin biomass is still available for exploitation. However, the catch has declined and mesh size regulation is difficult to implement as the dol net is a multispecies gear. One of the best measures for the fishery to sustain is by fishers themselves is that they suspend fishing activities when the catch is poor and non-remunerative.