The crucian carp biological characteristics in the ichthyofauna of Belgorod water storage reservoir

The authors carried out a comprehensive study of crucian carp population in the initial spawning period in the ichthyofauna of the Belgorod water storage reservoir, located on the territory of two regions with different ecological situations and anthropogenic load, with the third class of water quality (moderately polluted) in terms of hydrobiological and hydrochemical indicators. It was found that in terms of such linear-dimensional indicators as total body length, body length from the snout to the end of the scale covering, head length, length of the trunk, body depth and girth, crucian carps were characterized as normally developed. At the same time, there was a prevalence of juvenile animals in the catch over the old ones, females over males with their normal ratio, with well-developed reproductive products (hard roe and milt), immune organs (gills, liver, spleen), fatness corresponding to the standard, high yield of carcasses, with no evidence of any diseases during visual morpho-pathological examination, which indicated a favorable habitat for the crucian carp.