Growth characteristics of Uranoscopus scaber Linnaeus 1758, inhabiting the Iskenderun Bay (Northeastern Mediterranean)

Abstract

This study aimed to determine the age and some growth characteristics of Atlantic stargazer (Uranoscopus scaber) from Iskenderun Bay (Northeastern Mediterranean). For this purpose, a total of 150 Atlantic stargazer ranging in size from 9.1 to 28.0 cm in total length (weight: 11.7-345.7 g) were collected as by-catch from a commercial trawl fishing boat at a depth of 80-100 m between May 2015 and January 2016. The bottom trawl gear used was equipped with a 44 mm stretched mesh size net at the cod-end. The percentage of females and males were 46.7% and 53.3% respectively. The total length-weight relationships equation with coefficient of determination (R-2) were found as W = 0.011*TL3.131, R-2 = .9728, for all individuals, W = 0.015*TL3.021, R-2 = .9512 for females and W = 0.0102*TL3.136, R-2 = .9553 for males. By using the von Bertalanffy equation, the growth parameters of Atlantic stargazer were estimated to be L-infinity = 42.35 cm, k = 0.098, t(0) = -1.8474 for all individuals; L-infinity = 36.92 cm, k = 0.138, t(0) = -1.2693 for females and L-infinity = 38.77 cm, k = 0.1, t(0) = -2.334 for males. In this study, age reading was done by two independent readers and index of average percentage error (IAPE) was calculated as 6.1%. The highest condition factor value calculated as 1.81 in the age group 6 and the lowest condition factor value was calculated as 1.48 in the age group 1.