Home – Home – Jornals – Contemporary Problems of Ecology 2016 number 2

Population-genetic study of five coregonid fish species dwelling in the Pechora River system was carried out using 30 enzyme loci. The studied species were: whitefish, a natural hybrid of vendace and least cisco, inconnu, peled and Arctic cisco. The investigation revealed rather low intraspecific genetic differentiation among the fishes of Lower Pechora and Usa River which is the main tributary in the Pechora River basin where coregonid fishes migrate to spawn. Presumably whitefish, vendace and inconnu, which inhabit the main channels of Lower Pechora River and Usa River, are represented by introgressive populations of species originated from a mix of discrete evolutionary lineages. Some lineages of whitefish, vendace and inconnu from the West Siberian periglacial lake had come to Eastern Europe together with peled, broad whitefish and Arctic cisco with the last migration wave from Western Siberia during the Middle Weichselian glaciation (60-50 thousand years ago), whereas in the Eastern European periglacial refugium (Lake Komi) local lineages of these species had survived. Lake Komi could have been located on the Pechora Plain since the Early Weichselian glaciation (90-80 thousand years ago), and the studied whitefish specimens of the Upper Pechora River are probably the “purest” descendants of the periglacial race of whitefish from Lake Komi. This supposition is supported by the data on the high level of genetic differentiation between the whitefish of Upper Pechora and Lower Pechora ( D_N = 0.005), as well as the pattern of allele distribution of some polymorphic loci. In our opinion, ecologic and genetic differentiation of vendace in the Pechora River basin is also connected with the interaction between two evolutionary lineages that originated from independent periglacial refugia.