Effective Size of the Early-Run Sockeye Salmon <Emphasis Type="Italic">Oncorhynchus nerka</Emphasis> Population of Lake Azabach’e,Kamchatka Peninsula Evaluation of the Effect of Interaction between Subpopulations within a Subdivided Population

The effect of subdivision on the effective size (N _e) of the early-run sockeye salmon Oncorhynchus nerka population of Lake Azabach’e (Kamchatka Peninsula) has been studied. The mode of this effect is determined by the relative productivity of the subpopulations and its magnitude, by the rate of individual migration among subpopulations and genetic differentiation. If the contributions of subpopulations (offspring numbers) are different, genetic differentiation can reduce the N _e of the subdivided population. At equal subpopulation contributions, genetic differentiation always increases the N _e of the subdivided population in comparison with a panmictic population. We have found that all sockeye salmon subpopulations of Azabach’e Lake produce equal offspring numbers contributing to the next generation. The genetic differentiation between sockeye salmon subpopulations is low, and the subdivision increases the N _e of the early-run race with reference to the sum of the effective sizes of the subpopulations by as little as 2%.__________Translated from Genetika, Vol. 41, No. 5, 2005, pp. 680–685.Original Russian Text Copyright © 2005 by Efremov.