Estimation of population structure, growth and condition of Lates calcarifer (Bloch, ‎‎1790) in the Bay of ‎Bengal

Abstract

The current study illustrates the life-history traits; including length frequency distribution ‎‎(LFD), length-weight and length-length relationship (LWR and LLR), condition factors ‎‎(allometric, KA; Fulton’s, KF; relative condition, KR; relative weight, WR), and natural ‎mortality (Mw) of Lates calcarifer from the Bay of Bengal, Bangladesh. A total of 103 ‎individuals were randomly collected from January to December 2021 using traditional ‎fishing gear including Koral net and gill net. For each individual, total length (TL), ‎standard length (SL), and total body weight (BW) were measured with measuring scale to ‎‎0.1 cm and digital balance to 0.1 g precision, respectively. The TL size class 84.0 cm was ‎a numerically dominant group in the population. The b value of LWR (TL vs. BW) ‎indicated positive allometric growth (b=3.28) pattern in the Bay of Bengal. Likewise, the ‎b value of LLR indicated also the same growth pattern. Among the four types of ‎condition factors, KF is the best-suited tool for evaluating the well-being of L. calcarifer. ‎Additionally, WR exhibited significant divergence from 100 (P< 0.0001), defining an ‎imbalanced habitat. The calculated Mw was 0.23 year-1 for L. calcarifer. Therefore, these ‎findings would be used in the future for the improved management of this species in the ‎Bay of Bengal as well as for connecting ecosystems.‎