# Volgograd reservoir

## REGULARITIES OF THE RATIO OF THE SHELL LENGTH TO THE INDIVIDUAL WEIGHT OF MOLLUSKS FROM THE DREISSENA GENUS (DREISSENIDAE, BIVALVIA) IN THE VOLGOGRAD RESERVOIR

A regression analysis of the size and weight structure of the dreissenidae (D. bugensis and D. polymorpha) from the Volgograd reservoir was carried out. The power-dependence parameters in the resulting equation are different for the two mollusk species studied (W = 0.036L3.33 for D. bugensis and W = 0.064L3.32 for D. polymorpha). The established regression relationship between the individual body weight (W) and the mollusk’s shell length (L) has a high correlation degree: R2 = 0.96 for p = 0.01.

## ASSESSMENT OF THE IMPACT OF MAJOR LIMITING FACTORS ON THE GROWTH OF A VIMBA BREAM POPULATION (VIMBA VIMBA VIMBA) (CYPRINIDAE) - AN INTRODUCED SPECIES IN THE VOLGOGRAD RESERVOIR

An attempt was made to estimate the impact of major limiting factors on changes of the vimba population size in the Volgograd reservoir. The vimba population size in the reservoir is already close to its limit by one hypothesis, based on the accessibility of spawning area resources. A 15-fold increase in the vimba population size is possible for at least two decades by another hypothesis, providing for the population restriction by food resources.