THE ABUNDANCE AND SPECIES COMPOSITION OF STURGEON IN THE NORTHERN CASPIAN SEA

This study was carried out in the northern Caspian Sea on Gidrobiolog vessel in summer 2006 to assess the abundance and species composition of sturgeons. We used bottom trawl (9m) and gillnets with mesh size 60, 110, 250 and 29Omm. Totally 104 sturgeons were caught which included ten Acipenser guldenstadtii (69.9%), two Acipenser persicus (15.4%) and one Acipenser stellatus (7.7%) in the trawl samples. The species caught by gillnet were 34 Acipenser guldenstadtii (37.4%),53 Acipenser persicus (58.2%) and four Huso huso (4.4%). The average total length and weight of Acipenser guldenstadtii caught by trawl were 65.8±5.14cm and 1248.5±495.75g respectively and for those caught in gillnet were 83.14±2.99cm, 3101±443.66g. The average total length and weight of Acipenser persicus caught by gillnet were 75±3.60cm and 1806.79±158.05g.