Reproduction and Seasonal Growth Estimates of the Black Goby, Gobius niger (Osteichthyes: Perciformes: Gobiidae) in the Southeastern Black Sea Region of Turkey
Abstract
Seasonal growth pattern and reproductive biology of the black goby, Gobius niger, were studied in southern Black Sea between December 2012 and November 2013. The seasonal von Bertalanffy growth parameters, computed from ELEFAN, were estimated as L∞ = 11.90 cm TL, K = 0.701 year-1, C = 0.633, and WP = 0.492 for the Hoenig seasonal model and as L∞ = 12.14 cm TL, K = 0.680 year-1 for non-seasonal von Bertalanffy model. The size at sexual maturity (TL50) was estimated as 8.9 cm TL. The GSI ranged 0.60 in December and 8.57 in April (mean 3.82±0.818) for females and between 0.61 in October 2013 and 2.90 in May 2013 (mean 1.70±0.260) for males. The seasonal growth was pronounced probably due to reproduction activity which extended investment of energy in reproduction causing slower growth. The GSI development was related to photoperiod and the monthly variations of GSI values indicating that the intensive spawning occurred between April and August. During spawning time, the mean GSI value of females (6.04±1.177) was 2.9 times higher than the mean GSI values of males (2.08±0.423) (P < 0.05). The results of this study were offered as biological input parameters regarded as a reference for the conservation and management of the Black Sea stocks of the black goby.
Keywords
Black goby, Gobius niger, reproduction, seasonal growth
Recep Tayyip Erdoğan University, Scientific Research Project Office
We thank to Ozay Köse, Burak Taşçı, Yusuf Ceylan and Ahmet Kalkavan for their help in the field work. This study was conducted in accordance with ethics committee procedures of animal experiments. This work was supported by Recep Tayyip Erdoğan University, Scientific Research Project Office (grant number 2010.103.03.1).