Stock assessment of bonyfishes in the Iranian water of the Caspian Sea ( 2001 2002 )

Abstract

For gathering of data on biometry and catch statfstics, 5, mobile working group in the regions of Anzali , Kiashahr , Noshahr , Babolsar and Torkaman . Were involved from the start to the end of fishing season. After gathering,data Were intered to the computer based on species. For data analysis different methods Were undertaken sach as Bertalanfy equation for growth parameter Beverton and Holt for total mortality rates, pauly's imperical model for natural mortality rate and cohort Analysis for biomas estimation. The total recorded Catch in 2001 and 2002 was 10529 and 9566 tonnes. Totall catch with taking into account of pauching . estinmated 16200 and 15200 tonnes .total catch of Katum in 2002 had 1200 tonnes decrease with comparison of last year. Biomass of kutum in IRanian coastal Water of the Caspian sea in 2002 estimated about 15000tonnes. The catch of golden mullet in 2001 and 2002 was estimated 4218 and 6183 tonnes.that about 29%-38% of the catch of this species was undersize .The biomass of golden mullet estimated about 16400 tonnes. The small nose mullet in 2002 comprise 9% of mullet catches. The catches of common carp in Anzali region was very low .but stocks of this species in Gorgan region is in better condition which.Most of catches of this species were fished illgally in the Gorgan bay and Gomishan coastal creek. The biomass of this species was estimated 1140 tonnes Most of catches of the roach.were fished illgally .Totall catches of this species in 2002 were estimated about 738 tonnes. The catch of pickperch in 2002 were estimated about 30 tonnes.Most of the chatch of pickperch was immature and undersize. Appooximattelly all of the catch is due to releasing of fingerling of this species by fishery company. Totall catch of bream in 2002 was estimated 38 tonnes that most of which was immature and undersize.