Researchers led by head of the Laboratory of Hydrobiology and Fish Research of the Institute of Biology of the Mongolian Academy of Sciences, Dr. Ch.Ayushsuren conducted a resource study in Buir, Ugii and Dood Tsagaan lakes under the theme “Primary products of Mongolian lakes”. The researchers estimated that the catchable fish stock of Buir Lake is 360 tons, and it is estimated that 55 tons to 70 tons can be extracted per year. In 1954, according to a survey conducted in the Buir Lake, 77 percent were pike, eight percent were roach, five percent carp, three percent white pike, and two percent were taimen. However, it has decreased to 57 percent of carp, 17.5 percent of pike, and 8.5 percent of the silver division.

The biological resources of Dood Tsagaan Lake are estimated at 56.2 tons, and the catch is eight to 11 tons. In the 1970s, 70 percent of the lake’s stock was made up of white fish alone, but in recent years, it has increased to 52 percent due to grayling. It was found that the body size of pike, roach, and thalamus fish decreased significantly, while the size of the carp fish did not change much.

Moreover, the reserves of Ugii Lake were estimated at 80.6 tons. It was concluded that it is appropriate not to exceed 15 to 20 percent of the total stock when fishing. As a result of hydro chemical research, it became clear that these lakes were exposed to large amounts of organic pollution, and the species of native fish were reduced, and the growth and survival rate of some of them increased dramatically. The researchers concluded that the decrease in fish stocks is mainly caused by pollution caused by illegal fishing, waste, animal impacts, water use, and fertilizers used in agriculture.