Length-Weight Relationships and Condition Factor of Four Threatened Riverine Catfish Species in the Meghna River Estuary, Bangladesh

The current study examined the length-weight relationships (LWRs), length-length relationships (LLRs), and condition factor (K) of four threatened riverine catfish species (Pangasius pangasius, Rita rita, Sperata aor, and Bagarius bagarius) sampled from the Meghna River Estuary (MRE), Bangladesh. A total of 578 individuals were collected from contracted fishermen between January and October 2022. The length and weight of each species exhibited a highly positive correlation. The regression coefficient was 2.24 for P. pangasius, 2.90 for R. rita, 2.91 for S. aor, and 3.25 for B. bagarius. Furthermore, all species demonstrated a highly positive correlation between total length and standard length (r > 0.90). The calculated condition factor (K) values were 0.87 for P. pangasius, 1.18 for R. rita, 0.66 for S. aor, and 0.99 for B. bagarius indicating variations among the species. This study provides the first comprehensive documentation of all four major catfish species found in the MRE.