Species composition of bonyfish in the Iranian waters of the Caspian Sea during 1927-2013

In the present study, the catch composition of bony fishes (according to catch datarecorded by Iran Fishery and Fishstat Plus website) was investigated in the Iranianwaters of the Caspian Sea during 1927-2013 (in three periods, pre-decreasing seelevel, decreasing and increasing see level). The amount of catch and catchcomposition were compared using ANOVA and χP2P test, respectively. The resultshowed that the total catch of bony fishes was about 8000 mt in the years 1927-1935which declined to less than 500 mt in the years 1961-1964. In 1965-1978, the catchincreased to 5000 mt, after decreased to less than 1000 mt in 1979-1981. Since 1981the catch had an increasing trend. In the years 1992-2013, total catch was more than10000 mt and maximized 24000 mt. At the beginning of the period, the species ofRutilus rutilus, Rutilus frisii kutum (kutum), Stizostedion lucioperca, Aspius aspius,Silurus glani and shads were predominated in the catch. Since 1956, the catch speciescomposition changed and only kutum and mullets dominated and comprised the bulkof the catch. During last three decades, the main reason of this species diversityreduction is destruction of spawning grounds and the artificial propagation forrestocking has been concentrated on kutum.

Keywords:

Commercial catch , species composition , Caspian Sea , Iran