Growth, mortality and stock assessment of kelee shad, Hilsa kelee (Fam: Clupeidae) in the coastal waters of Pakistan

Abstract

Growth of kelee shad, Hilsa kelee, in the coastal waters of Pakistan was estimated from the lengthfrequency samples. The von Bertalanffy growth equation was Lt = 23.10 (1 − exp (−0.94(t + 0.18))). Estimated parameters of total mortality (Z), natural mortality (M) and fishing mortality (F) were 2.08 year−1, 1.78 year−1, and 0.30 year−1 respectively. The length-at-first capture was Lc = 10.88 cm. Biomass per recruitment (B/R) and yield per recruitment (Y′/R) were 0.87 and 0.031 respectively. The annual exploitation rate was U = 0.12. The exploitation ratio for maximum yield per recruit Emax = 0.73 and fishing mortality for maximum yield per recruit Fmax = 1.52; biological reference point Fopt = 0.89 year−1 and Flimit = 1.18 year−1. Present estimations showed that the natural mortality was higher than fishing mortality in Hilsa kelee, indicating that the state of the stock is sustainable and the fishery of kelee shad should not be increased beyond current levels in the coastal waters of Pakistan.