Abstract

Information on the length-weight relationship (LWR) and condition factor (K) of the common smooth-hound shark, Mustelus mustelus collected from fish landing sites located in the coastal areas of Lagos and Ondo States, Nigeria were provided in this study. The sharks were collected from March 2018 to September 2021. In total, 1,018 sharks were measured to the nearest centimeter with a tape measure for their total length while total weight was measured to the nearest gram on a digital balance. The linear regression equation for males, females and combined sexes using log-transformed length-weight relationship revealed a positive allometric growth (b>3) for the females and combined sexes while the males showed negative allometric growth reflecting a comparatively slower growth rate in total weight than in total length throughout the species ontogeny. The analysis of variance indicated a significant difference (P< 0.05) in the length and weight of the female M. mustelus sharks in both sampling locations. The newborn (TL < 50cm), medium (90cm≤TL<110cm) and large (TL≥110) size classes recorded a mean condition factor value of 0.4 while the young (50cm≤TL<70cm) and small (70cm≤TL<90cm) size classes had mean condition factor value of 0.3. The lowest K was recorded in October 2018; (0.33) while the highest K value was in January 2019; (0.43). The information obtained from this study would contribute greatly to the efforts to enrich the database on shark fisheries in Nigeria to achieve a better management of this critical species.

 Key Words: Mustelus mustelus, Length-Weight Relationship, Condition factor, Ecology, Nigeria