Population-genetic structure of the sterlet Acipenser ruthenus L., 1758 in the Mologa River during its re-acclimatization

Abstract

This paper examines the size-age structure, growth and genetic polymorphism of the sterlet population of the Mologa River, Vologda Oblast, formed during reacclimatization measures. The introduction of sterlet into the Mologa River began in 2016, and since 2018 it has been found in research catches. In the channel medial sections of the river, the proportion of sterlet in total catches ranged from 31.4% to 49.3% in numbers and from 26.0% to 64.0% in biomass. In 2022, the catches included fish with a length of 22–51 cm and a weight of 64–958 g of five age groups. The size, weight and age composition of the emerging population is currently determined by the number of juvenile sterlet released in individual years. Mitochondrial DNA analysis revealed 23 different mtDNA haplotypes and low relative haplotype diversity. The level of observed nuclear DNA heterozygosity averaged 0.567 with a range from 0.149 to 0.871. Genetic heterogeneity of individuals in the emerging population of sterlet from the Mologa River is sufficient for the local population of a river.

Keywords

• size-age structure
• linear growth
• weight growth
• microsatellite loci
• alleles
• mitochondrial dna
• haplotypes
• genetic polymorphism