Photo of Anthony Gharrett

Contact Information

Fisheries Division
11120 Glacier Highway
UAF Fisheries Division
Juneau, AK 99801
Phone: (907) 796-6445
a.gharrett@uaf.edu

Anthony Gharrett Professor

Fisheries Genetics and Aquaculture

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.

Publications

Geiger, H.J., I. Wang, P. Malecha, K. Hebert, W.W. Smoker, and A.J. Gharrett. 2007. What causes variability in pink salmon family size? Transactions of the American Fisheries Society. 136:1688-1698.
Garvin, M.R., and A.J. Gharrett. 2007. DEco-TILLING: An inexpensive method for SNP discovery that reduces ascertainment bias. Molecular Ecology Notes. 7:735-746.
Li, Z., A.K. Gray, M.S. Love, A. Goto, T. Asahida, and A.J. Gharrett. 2006. A key to selected rockfishes (Sebastes spp.) based on mitochondrial DNA restriction fragment analysis. Fishery Bulletin 104:182-196.
Li, Z., A.K. Gray, M.S. Love, T. Asahida, and A.J. Gharrett. 2006. Phylogeny of members of the rockfish (Sebastes) subgenus Pteropodus and their relatives. Canadian Journal of Zoology 84:527-536.
Gray, A.K., A.W. Kendall, Jr., B.L. Wing, M.G. Carls, J. Heifetz, Z. Li, A.J. Gharrett. 2006. Identification and first documentation of larval rockfishes (Sebastes spp.) in Southeast Alaskan waters was possible using mitochondrial markers but not pigmentation patterns. Transactions of the American Fisheries Society. 135:1-11.
Gharrett, A.J., A.P. Matala, E.L. Peterson, A.K. Gray, and J. Heifetz. 2005. Two genetically distinct forms of rougheye rockfish (Sebastes aleutianus) are different species. Transactions of the American Fisheries Society. 134:242-250.
Gilk, S.E., I.A. Wang, C.H. Hoover, W.W. Smoker, S.G. Taylor, A.K. Gray, and A.J. Gharrett. 2004. Outbreeding depression in hybrids between spatially separated pink salmon (Oncorhynchus gorbuscha) populations: Marine survival, homing ability, and variability in family size. Environmental Biology of Fishes 69:287-297.
Churikov, D. and A.J. Gharrett. 2002. Comparative phylogeography of the two pink salmon broodlines: an analysis based on mitochondrial DNA genealogy. Molecular Ecology 11:1077-1101.

Book chapters
Gharrett, A.J. 2006. The Genetics of fishes, Chapter 28. Pages 551-597 In M. Barton, Bond’s Biology of Fishes, 3rd edition. Thomson Brooks/Cole Publishers, Belmont, CA.
Gharrett, A.J., and L.A. Zhivotovsky. 2003. Migration. P. 141-174, in E.M. Hallerman [ed.] Population genetics: Principles and applications for fisheries scientists. American Fisheries Society, Bethesda, MD.

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.