Aceh Journal of Animal Science (2020) 5 (2): 68-72 Aceh Journal of Animal Science Journal homepage: www.jurnal.unsyiah.ac.id/AJAS * Corresponding author. Email address: henry.dienye@uniport.edu.ng Printed ISSN 2502-9568; Electronic ISSN 2622-8734 This is an open access article under the CC - BY 4.0 license (https://creativecommons.org/licenses/by/4.0/) Growth pattern of three species of Mullets (Pisces: Mugilidae) in Sombreior River, Rivers State, Niger Delta, Nigeria Henry Eyina Dienye*, Olaniyi Alaba Olopade Department of Fisheries, Faculty of Agriculture, University of Port Harcourt Choba Nigeria.P.M.B.5323 ARTICEL INFO ABSTRACT Keywords: Mugildae Length-weight relationship Condition factor Sombreior River Received: 8 January 2020 Accepted: 24 March 2020 Available online: 12 May 2020 DOI: 10.13170/ajas.5.2.15388 Length-weight relationships (LWRs) and condition factor are important biological information to assess the growth pattern and wellbeing of fish species influenced by numerous abiotic and biotic factors. To date, no data on the LWRs and condition of mullets in Sombreior River, Niger Delta. Hence, this research was conducted to determine abundance, length–weight relationship and Fulton’s condition factor (K) of three species of fish belonging to family Mugilidae in Sombreior River, Nigeria. There were a total of 248 samples from five sampling stations for a period of months. Fish species were of various sizes ranging from 24.66±0.40 to 26.35±0.26cm in length and 141.41±6.30 to 161.56±5.87g in weight. For the three species, slope (b) values ranged from 2.18 to 2.68 indicating a negative allometric growth of all fish species. The mean condition factor ranged from 0.89±0.03 forsix Mugil cephalus to 0.93±0.03 for Parachelon grandisquamis while the coefficients of determination (R 2 ) of the LWR regressions ranged between 0.64 (Neochelon falcipinnis) and 0.79 (Parachelon grandisquamis). It was concluded that the mullets in the Sombreior River had a negative allometric growth pattern and the condition is showing the species were in good state of well-being since mean K values are greater than 1. Introduction The Mugilidae family includes 17 genera and 72 valid species, which are found in freshwaters, estuaries, brackish water, hypersaline lagoons and coastal marine waters at shallow depths less than 20m. (Cardona, 2006). Species belonging to these genera are mostly benthic in their food habits (FAO, 1990). Mugil and Liza, are the two most important genera, which have 18 and 24 species respectively (Thomson, 1966; Nelson, 2006). In West Africa, mullets fish have high economic value (FAO, 2005) because they have high meat quality and very palatable taste (Asuquo et al., 2015). The biological information on fish are important and efficient approaches for their management and preservation. Biological data such as body length and weight constitute necessary data to assess population structure (Froese, 2006). Length-weight relationship is essential method for adequate use and control of the abundance of the fish species (Anene, 2005). The association between total length and other body weight is helpful in maintaining the taxonomic characteristics of the species (Pervin and Mortuza, 2008). The regression-based isometric and allometric relationships are also useful for calculating the body composition of fish and other animals in the production sector (Dumas et al., 2007). Condition factor is commonly used as a growth and feeding index (Fagade, 1979). Established assumption revealed that bigger fish of a given measurement are in healthier physiological state (Bagenal, 1978). Condition factor is likewise a valuable guide to track feeding strength, stage, and growth rates in fish (Oni et al., 1983). This is highly affected by both biotic and abiotic conditions and can possibly serve as an index for determining the state of the aquatic environment of the fish (Anene, 2005). Condition factors of various tropical fish species were studied and stated