Anthony Gharrett Professor

Research Overview

Genetics is important in both the management and culture of fishes. Because production is greatest in populations adapted to their environments, it is as important to avoid disrupting pre-apted, naturally producing populations as it is to select for populations that thrive in culture. Of particular interest to me is the distribution of genetic variability of a species. Unique heritable characteristics may define a population; differences among populations are used to estimate compositions of mixed stock fisheries. Genetic similarities among populations are used to infer relationships which may reflect biological characteristics such as migration route and run timing or even post-Pleistocene colonization and evolutionary relationships.

Maintenance of genetic variability is a goal for most cultured fish populations. Loss of variation is generally accompanied by a decline in performance. Monitoring the genetic composition of a cultured population is one means of assuring that culture practices are appropriate. In the past, genetic variability has been elucidated primarily using starch-gel electrophoresis. However, recent advances in DNA technology have introduced new, powerful techniques for resolving genetic differences in mitochondrial DNA and nuclear DNA sequences, in particular microsatellite loci. We are now using DNA sequence-based methods to investigate salmon and rockfish population and evolutionary genetics.

Selected Publications

Gharrett, A. J., W. W. Smoker, R. R. Reisenbichler and S. G. Taylor. 1999. Outbreeding depression in hybrids of even- and odd-broodline pink salmon (Oncorhynchus gorbuscha Walb.). Aquaculture 173:117-129.

McGregor, A. J., S. Lane, M. A. Thomason, L. A. Zhivotovsky, W. W. Smoker and A. J. Gharrett. 1998. Migration timing, a life history trait important in the genetic structure of pink salmon. North Pacific Anadromous Fish Commission Bulletin No. 1:262-273.

Hebert, K. P., P. L. Goddard, W. W. Smoker and A. J. Gharrett. 1998. Quantitative genetic variation and genotype by environment interaction of embryo development rate in pink salmon (Oncorhynchus gorbuscha). Canadian Journal of Fisheries and Aquatic Science 55:2048-2057.

Carney, B. L., A. K. Gray and A. J. Gharrett. 1997. Mitochondrial DNA restriction site variation within and among five populations of Alaskan coho salmon (Oncorhynchus kisutch). Canadian Journal of Fisheries and Aquatic Science 54:940-949.

Geiger, H. J., W. W. Smoker, L. A. Zhivotovsky and A. J. Gharrett. 1997. Variability of family size and heritability of marine survival in pink salmon have implications for conservation biology and human use. Canadian Journal of Fisheries and Aquatic Science 54:2684-2690.