The Sterlet Acipenser ruthenus (Acipenseridae) in the Nizhnekamsk Reservoir: Structure of Catches, Biological Parameters and Prospects for Stock Use

Currently, the size and age composition of the sterlet Acipenser ruthenus in the Nizhnekamsk Reservoir have significantly decreased. Due to the decrease in the area of breeding grounds for the species, its feeding area is also localized, extending mainly to the upper reaches of the reservoir. Long maturation of females, breeding gaps and relatively low fecundity rates lead to a reduction in the sterlet population. The state and size of the commercial stock of the species currently do not exceed the critical values of the management guidelines, which indicates that the population remains within the safe boundaries of fishing.