Length-Weight Relationship and Relative Condition Factor of Hilsa (Tenualosa Ilisha) Fishes in the Bay of Bengal, Bangladesh

The present study describes the associated relationship between the length-weight, sex ratio and related condition factor of Tenualosa ilisha based on the length and weight data collected from the commercial landing station of BFDC, Cox’s Bazar, from January 2019 to December 2019. The work was carried out on 866 specimens (307 male and 559 female) ranging from 8.4 to 53.6 cm in length and weight of fishes ranging from 7 to 1977g, respectively. The reproductive attributes of T. ilisha appeared in the sex proportions (M: F=1:2) which revealed the prevalence of females in comparison with males. The external observation was taken into consideration to determine the gender of Hilsa. The relationship of length-weight was fitted with the pooled data for males and females independently of all month-to-month samples which results the BW=0.0104TL2.9795 (R2=0.9636) and BW=0.0019TL3.4689 (R2=0.8461) respectively. The results expressed a higher correlation in between the length-weight (r>0.91). The length wise relative condition factor of T. ilisha was estimated as 1.02, 0.9, 1.05, 1.03, and 1.02 at the length group of 0-20, 21-30, 31-40, 41-50, 51-60 respectively indicating fluctuation of condition factor within the size group. The overall KR for T. ilisha was 0.9-1.22 in which maximum KR was found in July while the minimum was in March. The KR was strongly correlated with TL and BW.