Current state of sympatric whitefish from Lake Pyaozero, Kovda river basin, Karelia

Abstract

The study of whitefish from Pyaozero Lake (White Sea basin) has shown that three forms of sympatric whitefish occurring in the lake are abundant. They clearly differ from each other, but the existing forms/species are similar in countable characters. The evolution of modern White Sea basin populations is associated with the postglacial colonization and hybridization of several genetically distant whitefish forms, This factor is assumed to have given rise to populations with various morphological and ecological characteristics, e.g. growth rate and maturation time. The fact that haplotypes in the morpho-ecological groups of whitefish are highly mixed is consistent with the heterogeneity of the haplotypes revealed earlier in Kamennoye Lake, Kem River basin. Analysis of a gene of ND1 mtDNA has shown that two major phylogenetic whitefish lineages, from which Pyaozero whitefish has derived, are of European origin, while the third one is closely related to whitefish from Siberian water bodies. The strong hybridization of ancestral phylogenetic whitefish lineages in the recent forms of Pyaozero whitefish is also indicated by evidence for the genetic variability of allozymic loci. Recent paleolimnological reconstructions suggest that the origin of multi-rakered whitefish from Karelia’s lakes is associated with the postglacial colonization of an old multi-rakered whitefish lineage, whose relict populations have preserved in the old lakes of the White Sea-Kuloy Plateau unaffected by Lower Quaternary glaciation.