Some population parameters of Bengal yellowfin seabream, Acanthopagrus longispinnis (Val.), from Hatiya Island, Bay of Bengal

Size frequency, length-weight relationships (LWRs), length-length relationships (LLRs), and relative condition factor (K_n) was studied in an estuarine fish the Bengal yellowfin seabream, Acanthopagrus longispinnis (Val.), from Hatiya Island in the Meghna River estuary. Specimens were caught with fixed purse nets of two mesh sizes (0.2 to 0.5 inch and 2.0 to 2.5 inch) from January to March 2020. The total body length of A. longispinnis ranged between 5.8 and 9.3 cm throughout the sampling period. The length-weight relationships for A. longispinnis was highly significant (p < .001), and the adjusted r² value was 0.921. The calculated growth coefficient (b) for A. longispinnis was 3.163, which indicated a hyperallometric growth pattern. The length-length equation TL = 1.1384 SL + 0.4899 for unsexed A. longispinnis was highly significant (p = 0.001, r² = 0.951). There were no significant variations in relative condition factors among the specimens of different length classes (5.5–9.5 cm). No information regarding length-weight or length-length relationships for A. longispinnis was previously reported in FishBase. Our estimated LWR and LLR parameters for A. longispinnis can be useful for management and conservation purposes of this estuarine species.