Life-history traits of grey mullet, Liza parsia in the Passur River of Southern Bangladesh: Implications for effective management

Abstract

The study of life-history features of least-concerned fishes like Liza parsia is critical for developing long-term management and conservation methods for this species. The current study delivers the very first detailed clarification of life-history traits (LHT), containing length-frequency distribution (LFD), length-weight and length-length relationships (LWR and LLR), form factor (a_3.0), condition factors, length at first sexual maturity (L_m), natural mortality (M_w) and optimum catchable length (L_opt) of L. parsia from the Passur River in southern Bangladesh. Fish samples (n =150) were randomly collected from May to August 2021, using gill nets. Each individual fish's total length (TL), fork length (FL), standard length (SL), and bodyweight (BW) were recorded. The size classes of TL were 15–17cmleadingmaximum sizes among the fish population. Length-Weight relations (LWR) from exponential b values (TL vs. BW) revealed a negative allometric growth trend (b = 2.6174). The b value based on the LLR similarly specifies the identical growth configuration. The a_3.0 score was determined to be 0.01, demonstrating that the fish has extended body morphology. K_F is the finest method for measuring the well-being of L. parsia in the Passur River among the four types of condition parameters. Moreover, W_R also showed a significant deviation from 100 (p < 0.05) signifying an unstable habitat for L. parsia. The calculated L_m, M_w and L_opt values were 11.20 cm in TL, 0.76/year and 12.64 cm in TL respectively.  As a consequence, the findings of this research could be conducted in the future to effectively manage this species in the Passur River, and its interconnecting environments.