Prospects of Svetlinskoye Water Storage Basin (Vilyui River Basin) Use for Commercial Fishing

Abstract

Commercial fishing development of natural reservoirs, aimed to develop a biological framework for their sustainable use, is based on a targeted formation of fish fauna and receiving production by means of the fullest use of trophic capacity. The study of fish fauna and food potential of Svetlinskoye water storage, formed in 2004 (being the second one in the Vilyui HPS cascade), has shown the absence of plankton-feeding fish and the presence of an excessive amount of plankton organisms. The introduction of peled to the reservoir will allow to fuller use the reserve animal plankton production, which made 9.5 g/m³ or 95 kg/ha for the growing season. By its feeding pattern, peled can be referred to the fish with a broad food spectrum. It feeds on animal plankton and animal benthos. But with high indicators of animal plankton amount, peled mostly feeds on plankton organisms, and young peled is a typical plankton eater. As by their biological parameters fish in Svetlinskoye water storage are mostly predators and benthos feeders, a considerable share of the animal plankton quite naturally remains unused. However, it should be taken into account that the water storage’s animal plankton is in different amounts a part of the food items of all the fish inhabiting it. On the condition that fish inhabiting in Svetlinskoye water storage eats 60 % of the animal plankton production, its remaining production makes 38 kg/ha, or 395,2 tons per the entire reservoir. With the feeding ratio equaling 10, the reserve production of the animal plankton will allow to expect the additional growth of the potential (estimated) ichtyomass size within 40 tons. To obtain similar potential mass of peled, with its average caught weight of 0,6 kg, it is necessary to introduce 3 million of viable larvae of 163 thousand of yearlings.