Temporal variations of length, weight, and condition of Hilsa shad, Tenualosa ilisha (Hamilton, 1822) in the Meghna River, Southeastern Bangladesh

Nima, Akhery; Hossain, Md. Yeamin; Rahman, Md. Ashekur; Mawa, Zannatul; Hasan, Md. Rabiul; Islam, Md. Akhtarul; Rahman, Md. Ataur; Tanjin, Sumaya; Sabbir, Wasim; Bashar, Md. Abul; Mahmud, Yahia

doi:10.21608/ejabf.2020.88776

Temporal variations of length, weight, and condition of Hilsa shad, Tenualosa ilisha (Hamilton, 1822) in the Meghna River, Southeastern Bangladesh

Document Type : Original Article

Authors

10.21608/ejabf.2020.88776

Abstract

The current study was on temporal variations of length, weight, and condition of Tenualosa ilisha (Hamilton, 1822) from the Meghna River, Southeastern Bangladesh for the period of July 2018 to June 2019. A total of 1433 individuals were collected from the Meghna River (Chandpur and Laxmipur region, SE Bangladesh). Bodyweight (BW) and total length (TL) were measured with 0.01 g and 0.01 cm accuracy for each specimen. The relative condition factor (K_R) was calculated by the equation of Le Cren (1951): K_R = W/(a×L^b) where W is the body weight (g) and L is the total length (cm) and a & b is the length-weight relationship parameters estimated with linear regression analyses. The value of K_R ~ 1 indicates good health, >1 indicates over bodyweight with compare to length, whereas <1 indicates a relatively poor condition of fish. The TL ranged from 15.3-57.8 cm while the BW was 37.17–2250 g. The overall K_R for T. ilisha was 0.65-1.66 in the Meghna River. The maximum K_R was found in July while the minimum was in January. The K_Rwas strongly correlated with BW in the Meghna River. These findings will help to improve the sustainable management policy of hilsa fishery in the Meghna river ecosystem and other adjacent water bodies.

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