Spatial and ecological structure of the sockeye salmon population Oncorhynchus nerka of Kuril Lake

Institute of Gene Biology Russian Academy of Sciences (FSBIS IGB RAS), group of bioinformatics, 34/5 Vavilova Street, Moscow, 119334, Russia

^* Corresponding author: mailfed@mail.ru

Abstract

This study examines the genetic structure of sockeye salmon populations in Kuril lake basin, focusing on the allelic frequencies of SNP loci that potentially carry an adaptive load. Our results reveal the division of sockeye salmon populations into three distinct groups: early river sockeye salmon and two groups of littoral sockeye salmon from the southern and northeastern shores of the lake. This division is supported by the genetic data, which shows that the populations are genetically distinct and have distinct allelic frequencies. Additionally, our analysis reveals that the neutral structure of the population is rather shallow, with only minor differences found between the two ecotypes of sockeye salmon - stream and littoral. These findings suggest that the genetic differences between the populations are primarily driven by adaptive processes, rather than neutral genetic drift.