Reproductive biology of the golden grey mullet, Liza aurata in the Iranian coastal waters of the Caspian Sea

The paper focuses on some of the biological characteristics of the golden grey mullet, Liza aurata in the Iranian waters of the Caspian Sea. Samples of commercial catch of mullet obtained by means of beach seine fishing cooperatives along the Iranian coasts of the Caspian Sea (2007-2008) as monthly interval. Samples were subjected to biometric measurement to specify their biological characteristics. The male/female ratio in the present study was 1:1.22 which deviated significantly from 1:1 common sex ratio (X2=7.7, Sig, level=0.006). During this study, the peak of the spawning time for the golden grey mullet occurred in October in waters off- Gilan shore whereas it occurred in November off Mazandaran and Golestan provinces. The highest Gonado-Somatic Index (GSI) was found to occur during late September and October which declined to its lowest level in November and December and remained relatively stable during January to April. Therefore, spawning of L. aurata started earlier in Gilan and ended later in Golestan Province. The average absolute fecundity of the golden grey mullet was 700881 ± 429987 ( ± SD) eggs with a range of 200112 to 2282862 eggs. The length of females at 50% sexual maturity of the golden grey mullet was estimated 28.4 cm.