Ojo  O.B.¹ , Olawusi-Peters O.O.² , Ajibare A.O.³

1 Department of Agricultural Science and Technology, Bamidele Olumilua University of Education, Science and Technology, PMB 250 Ikere-Ekiti, Ekiti State, Nigeria
2 Department of Fisheries and Aquaculture Technology, Federal University of Technology, Akure, Ondo State, Nigeria
3 Department of Fisheries and Aquaculture Technology, Olusegun Agagu University of Science and Technology, Okitipupa, Ondo State, Nigeria

Author    Correspondence author
International Journal of Aquaculture, 2025, Vol. 15, No. 6   doi: 10.5376/ija.2025.15.0027
Received: 15 Sep., 2025    Accepted: 31 Oct., 2025    Published: 17 Nov., 2025

This is an open access article published under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

Ojo O.B., Olawusi-Peters O.O., and Ajibare A.O., 2025, Length-weight relationship and condition factor of economically and ecologically important fish species in Ilaje LGA, Ondo State, Nigeria, International Journal of Aquaculture, 15(6): 275-286 (doi: 10.5376/ija.2025.15.0027)

Length–weight relationship (LWR) and condition factor (K) are critical parameters for evaluating fish growth patterns, stock status, and ecosystem health. This study examined Ethmalosa fimbriata and Chrysichthys macropogon from four coastal fishing villages; Ayetoro, Bijimi, Idiogba, and Asumogha in Ilaje Local Government Area, Ondo State, Nigeria. A total of 320 specimens were collected between April and July using gillnets of varying mesh sizes. Standard length and body weight were measured, and LWR parameters were estimated using log-transformed regressions, while Fulton’s condition factor was applied to assess fish health and habitat suitability. Results showed that both species exhibited allometric growth, with growth exponent (b) values significantly deviating from the isometric standard of 3. The condition factor for E. fimbriata ranged from 0.92 at Bijimi to 1.56 at Idiogba, while C. macropogon varied from 0.74 at Asumogha to 1.70 at Ayetoro. Higher K values at Idiogba and Ayetoro indicate relatively favorable habitats, whereas lower values at Bijimi and Asumogha suggest environmental stress and reduced food availability. Correlation analysis revealed a positive but site-dependent relationship between length and weight, with stronger associations in stations of higher habitat quality. These findings underscore the influence of habitat variability on fish condition and highlight the need for continuous ecological monitoring. The study provides a baseline for sustainable fisheries management and conservation strategies in Nigeria’s coastal waters.

Length–weight relationship; Condition factor; Allometric growth; Fisheries management; Coastal ecosystems; Nigeria