NUMBER AND BIOMASS OF WHITEFISH IN A FLOODPLAIN BODY OF WATER OF THE LOWER OB

On the basis of six years of research, data are given on the number, b iomass, and commercial reserve of whitefish (peled, muksun, broad whit efish, and Siberian whitefish) in one of the floodplain bodies of wate r of the Lower Ob: the Khanty-Pitlyar sor. The reasons determining var iations in ichthyomass are discussed. In fish biomass (7.79-17 72 kg/h a), continental sors of the Lower Ob are close to lakes of the oligotr ophic type. A conclusion is drawn about the need to create a fishery c lassification of the sor system in the Ob basin.