Genetic Comparison of Lake Michigan Chinook Salmon (Oncorhynchus tshawytscha) to211 Their Source Population

摘要

To determine whether genetic drift has impacted the genetic diversity of Lake211u001eMichigan chinook salmon since their transfer from Washington's Green River in the 211u001elate 1960's, the authors surveyed the allozyme variation of Lake Michigan chinook 211u001eat 18 loci that were variable in a 1980's survey of Green River chinook salmon. 211u001eThe genetic diversity of Lake Michigan chinook salmon was consistently less than 211u001ethat of their Green River conspecifics (2.17 vs. 2.56 alleles per locus, 17% of a 211u001evariable loci monomorphic in Lake Michigan fish). Lake Michigan chinook salmon 211u001ewere more closely related to Green River chinook than to those of a tributary of 211u001eWashington's Toutle River, a purported source population. The average yearly 211u001evariance effective population size (Ne) of Lake Michigan chinook from 1967 to 211u001e1995 was 378 individuals. This is less than 1% of the estimated average census 211u001esize, indicating that genetic drift has impacted the Lake Michigan population.