Age and growth of the needlefish, <i>Tylosurus imperialis </i>(Rafinesque, 1810) from the Levantine coast, North-Eastern Mediterranean

The present study is the first to determine the age and growth parameters of the needlefish Tylosurus imperialis in the Northeastern Mediterranean. A total of 320 specimens of T. imperialis were caught by gill nets from Turkish coasts (Iskenderun Bay) in the Northeastern Mediterranean between October 2020 and September 2021. The maximum age was 5 years for both sexes combined, and the age group 3-4 comprised 77.5 % of the samples. The total length distribution of T. imperialis was 60 to 109 cm, and the weight distribution was 309 to 1985 g. The b value was between 3.20 and 3.31 for females and males, respectively. The parameter b from the length-weight relationship characterizes a positive allometric growth. Growth equations were calculated as W=0.0006xL(3.2026) (R-2= 0.912) for females, W=0.0004xL(3.3163) (R-2= 0.896) for males, and W= 0.0005xL(3.2456) (R-2=0.904) for all specimens. Von Bertalanffy growth parameters were L-infinity= 139.29 cm, K= 0.119 year(-1), t(0)= -1.819 year for females, L-infinity= 138.50 cm, K= 0.113 year(-1), t(0)= -1.834 year for males and L-infinity= 138.33 cm, K= 0.112 year(-1), t(0)= -1.839 year for all specimens. The spawning period of T. imperialis was determined to be between April and August for both sexes. This data will be useful for the fisheries management of needlefish stocks in our study area and elsewhere.