Temporal patterns of genetic variation in a salmon population undergoing rapid change in migration timing
Article first published online: 18 APR 2013
© 2013 The Authors. Evolutionary Applications published by Blackwell Publishing Ltd.
This is an open access article under the terms of the Creative Commons Attribution License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited.
Volume 6, Issue 5, pages 795–807, July 2013
How to Cite
Kovach, R. P., Gharrett, A. J. and Tallmon, D. A. (2013), Temporal patterns of genetic variation in a salmon population undergoing rapid change in migration timing. Evolutionary Applications, 6: 795–807. doi: 10.1111/eva.12066
- Issue published online: 17 JUL 2013
- Article first published online: 18 APR 2013
- Manuscript Accepted: 4 MAR 2013
- Manuscript Received: 22 OCT 2012
- North Pacific Research Board. Grant Number: 1110
- Alaska Sustainable Salmon Fund. Grant Number: #45965
- climate change;
- genetic change;
- genetic divergence;
- genetic diversity;
- genetic effective population size;
Though genetic diversity is necessary for population persistence in rapidly changing environments, little is known about how climate-warming influences patterns of intra-population genetic variation. For a pink salmon population experiencing increasing temperatures, we used temporal genetic data (microsatellite = 1993, 2001, 2009; allozyme = 1979, 1981, 1983) to quantify the genetic effective population size (Ne) and genetic divergence due to differences in migration timing and to estimate whether these quantities have changed over time. We predicted that temporal trends toward earlier migration timing and a corresponding loss of phenotypic variation would decrease genetic divergence based on migration timing and Ne. We observed significant genetic divergence based on migration timing and genetic heterogeneity between early- and late-migrating fish. There was also some evidence for divergent selection between early- and late-migrating fish at circadian rhythm genes, but results varied over time. Estimates of Ne from multiple methods were large (>1200) and Ne/Nc generally exceeded 0.2. Despite shifts in migration timing and loss of phenotypic variation, there was no evidence for changes in within-population genetic divergence or Ne over the course of this study. These results suggest that in instances of population stability, genetic diversity may be resistant to climate-induced changes in migration timing.