Age, growth and reproduction of the sand smelt Atherina boyeri Risso, 1810 in the Gomishan wetland - southeast Caspian Sea

A total of 2256 specimens of Atherina boyeri caught in Gomishan wetland (a marsh lagoon located at the southeast Caspian Sea) during spawning season from February to August 2007 were examined for life-history attributes. The population has a 4-year life cycle. Length-weight relationship was estimated as W = 0.0053TL(3.0181) for males and W = 0.0050TL(3.063) for females, being allometrically positive for both sexes. The von Bertalanffy growth function fitted to back-calculated size at age data was: Lt = 155.17 [1 - exp - 0.28(t + 0.738)] and Lt = 162.77[1 - exp - 0.27(t + 0.727)] for males and females respectively. The sex ratio was 1:1.30 in favor of females. The reproductive season, evaluated from GSI, extended from March to July, with a peak in March. The average absolute and relative fecundities were 2976 eggs and 874 eggs g(-1) of body weight respectively. The diameter of oocytes ranged from 0.03 to 0.20 mm with a mean value of 0.68. The life-history patterns of A. boyeri in the population under study imply that the population of this species in the southeast Caspian Sea differs markedly from those of other localities of its range distribution. The differences were thought to be due to differences in geographical locations. (C) 2008 Elsevier Ltd. All rights reserved.