Length-weight relationship and well-being factors of 33 fish species caught by gillnets from the Egyptian Mediterranean waters off Alexandria

This study investigates the growth pattern of 33 fish species caught by gillnets from the Egyptian Mediterranean waters off Alexandria between 2018 and 2020. This is accomplished by studying the length-weight relationship (LWR), Fulton’s condition factor (kc), the allometric condition factor (ka), and the relative weight condition factor (kn). The b-values of the length-weight relationship of the studied species varied between 2.1382 and 3.6868 according to the results. Only Dentex macrophthalmus (b = 2.1382), Etrumeus golanii (b = 2.4197), and Trichiurus lepturus (b = 3.6868) exhibited different values than the expected range of 2.5 1) is not necessarily a better condition for the fish. The study of the allometric condition factor (ka) assessed that the difference between ka and kc values influenced by the feeding intensity and the b-value. The values of the relative weight condition factor (kn) were within the range from 0.929 to 1.038, and 24 fish species reflected a good growth condition while the kn values for the remaining 9 species were less than 1.0. The obtained results add new data about specific species and provide updated data on the remaining species in the area of study. The obtained results can have useful effects on the stock assessment of fish species.