Prospects for fisheries use of lake Sobache (Pionerskoe) in the Republic of Khakassia

Abstract

We assess Sobache (Pionerskoe) lake located in The Republic of Khakassia for aquaculture using. The lake is drainless, the water-surface area is about 1.5 km2. The prevailing depths range from 2 to 4 m. We provide data on the hydrological regime of the lake (temperature, dissolved oxygen level, chemical water composition). 3 species of rotifers, 10 species of cladoceran and 3 species of copepods were found in the zooplankton. The dominant complex consists of the rotifer Asplanhna priodonta, Bosmina longirostris and Ceriodaphnia quadrangula. The zoobenthos community includes 13 groups of organisms, where chironomids predominate in abundance, and gastropods and bivalves predominate in biomass. The ichthyofauna of the lake consists of perch and pike, perch predominates in abundance. Four species of parasites were found, including trematodes and myxporidia. The infection of fish with trematode metacercariae indicates the presence of intermediate hosts in the zoobenthos community of the lake. The detected species of parasites do not pose a danger to human health. The natural fish productivity is estimated at 48.2 kg/ha. We recommended to use the lake for commercial cultivation of fish in polyculture way. We proposed two schemes of fishery exploitation of the lake on the principle of pasturable fish culture: annual cultivation of fish in polyculture (carp, trout, herbivorous fish species) and joint cultivation of fish in polyculture (carp and white amur) by continuous intensive technology (three-year turnover) with carp feeding. The expected yield of fish products varies from 460.0 to 400.0 kg/ha, depending on the chosen technology. These recommendations can contribute to the effective use of the fisheries potential of Sobache (Pionerskoe) lake to provide the region with fresh fish products and create jobs for the local population.