నైరూప్య

STUDY ON GROWTH, MORTALITY AND LENGTH-WEIGHT RELATIONSHIP OF BIG EYE SHAD (Ilisha filigera) CAPTURED FROM SOUTH-EAST COAST OF BANGLADESH

Al Mamun*, KM Shahriar Nazrul, Md. Abdullah Al-Mamun, Suman Barua, SM Hasan Ali

Present study was conducted to investigate the growth parameters, length-weight relationship and different mortality rates of the population Ilisha filigera, the big eye shad from south-east coast of Bangladesh. From January 2013 to December 2014, a total of 852 individuals (both sex together) of fish specimens were collected and the respective analysis was done by using FAO-ICLARM stock assessment tools (FiSAT-II). The von Bertalanffy growth parameters, the asymptotic length L∞ (cm) and the growth constant K (year-1), were found to be 42.80 and 0.88, respectively. The growth performance index (Ø?) was found to be 3.207. The total length and body weight (L-W) relationship was found as W=0.116 L2.205, indicating that the growth rate showed negative allometric pattern (b=2.205<3) with a coefficient of determination (r2) value of 0.979. The annual fishing morality rate (F) was 1.04, whereas the natural mortality rate M (1.49) was comparatively higher than the fishing mortality. The obtained value of the exploitation rate (E=0.41) indicated that the said population was not in over-exploited condition.