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<br />Other Genetic Approaches
<br />
<br />The approaches outlined above were developed primarily
<br />for use with data provided by protein electrophoresis.
<br />Fortunately, such data are easily obtained, and large data
<br />sets are already available for all the anadromous salmonids
<br />in the Pacific Northwest. A number of other genetic tech-
<br />niques have been used to address similar or related problems
<br />in other organisms, and some of these are likely to play
<br />important roles in the future management of Pacific salmon.
<br />Included in this category are the analysis of restriction
<br />fragment length polymorphisms (RFLPs) in mitochondrial
<br />and nuclear DNA and the intentional genetic marking of
<br />certain stocks. Additional techniques currently being de-
<br />veloped include gene transfer, cryopreservation of gametes,
<br />and changes in ploidy or other chromosomal manipulations,
<br />but important ethical and ecological questions need to be
<br />resolved before they can be incorporated into management
<br />practices. Many of these genetic approaches are discussed
<br />in Parker et al. (in press).
<br />
<br />Conclusions
<br />
<br />Major management problems in Pacific salmon are largely
<br />a consequence of the distinctive life history features of these
<br />species. In particular, the strong tendency of salmon to
<br />form discrete freshwater populations permits individual
<br />breeding units to adapt and evolve independently of others.
<br />As a consequence, management strategies cannot be ex-
<br />pected to succeed without a clear understanding of genetic
<br />consequences of proposed actions. To date, full advantage
<br />has not been taken of genetic approaches developed in the
<br />last decade. The following measures are recommended:
<br />1. Expand GSI programs to include more fisheries for
<br />more species, and use the results to more effectively allocate
<br />resources among user groups, place temporal and spatial
<br />limitations on the catch, and preserve threatened or en-
<br />dangered stocks. Composition estimates can be obtained
<br />for individual stocks and combined as desired to address
<br />broader issues such as the relative contributions of hatchery
<br />vs. wild fish, U.S. vs. Canadian fish, or North American
<br />vs. Asiatic fish.
<br />2. Initiate a comprehensive, yearly sampling program for
<br />hatchery stocks to monitor the nature and extent of genetic
<br />changes. Results will provide the most direct means of
<br />evaluating the success or failure of hatchery practices de-
<br />signed to minimize effects of inbreeding.
<br />3. Evaluate the genetic consequences of proposed, large-
<br />scale supplementation programs. Archived baseline genetic
<br />data, together with information on life history traits, can
<br />be used in the initial screening process to select the most
<br />appropriate donor stock. Subsequently, a systematic mon-
<br />itoring program using genetic and meristic characters is the
<br />best way to monitor the genetic effects of supplementation.
<br />Traditional tagging methods provide no direct information
<br />regarding genetic impacts on the target slock or other stocks
<br />that might be incidentally affected. ~
<br />
<br />References
<br />
<br />Aebersold, P. B., G. A. Winans, D. J. Teet, G. B. Milner, and E
<br />M. Utter. 1987. Manual for starch gel electrophoresis: a method
<br />for the detection of genetic variation. NOAA Tech. Rep. NMFS
<br />61:1-19.
<br />
<br />24
<br />
<br />'-.
<br />
<br />Allendorf, E W., and N. Ryman. 1987. Genetic management of
<br />hatchery stocks. Pages 141-159 in N. Ryman and F. Utter, eds.
<br />Population genetics and fishery management. University of
<br />Washington Press, Seattle.
<br />Allendorf, F. W., and R. F. Leary. 1988. Conservation and distri-
<br />bution of genetic variation in a polytypic species, the cutthroat
<br />trout. Conserv. BioI. 2:170-184.
<br />Fraidenburg, M. E., and R. H. lincoln. 1985. Wild chinook salmon
<br />management: an international conservation challenge. N. Am.
<br />J. Fish. Manage. 5:311-329.
<br />Fredin, R. A. 1980. Trends in North Pacific salmon fisheries. Pages
<br />59-119 in W. J. McNeil and D. C. Himsworth, eds. Salmonid
<br />ecosystems of the North Pacific. Oregon State University Press,
<br />Corvallis.
<br />Grant, W. S., G. B. Milner, P. Krasnowski, and F. M. Utter. 1980.
<br />Use of biochemical genetic variants for identification of sockeye
<br />salmon (Ollcorhynclllls Ilaka) stocks in Cook rnlet, Alaska. Can.
<br />J. Fish. Aquat. Sci. 37:1236-1247.
<br />Johnson, J. K. In press. Regional overview of coded wire tagging
<br />of anadromous salmon and steelhead in Northwest America.
<br />American Fisheries Society Symposium 7.
<br />Kapuscinski, A. R., and D. P. Philipp. 1988. Fisheries genetics:
<br />issues and priorities for research and policy development. fish-
<br />eries (Bethesda) 13(6):4-10.
<br />Krimbas, e. B., and S. Tsakas. 1971. The genetics of Dacl/s oleae.
<br />V. Changes of esterase polymorphism in a natural population
<br />following insecticide control-selection or drift? Evolution 23:454-
<br />460.
<br />Krueger, e. e., A. J. Gharrett, T. R. Dehring, and E W. Allendorf.
<br />1981. Genetic aspects of fisheries rehabilitation programs. Can.
<br />J. Fish. Aquat. Sci. 38:1877-1881.
<br />Kutkuhn, J. H. 1981. Stock definition as a necessary basis for
<br />cooperative management of Great Lakes fish resources. Can. J.
<br />Fish. Aquat. Sci. 38:1476-1478. ,
<br />Larkin, P. A. 1981. A perspective on population genetics and
<br />salmon management. Can. J. Fish. Aquat. Sci. 38: 1469-H73.
<br />Leary, R. E, F. W. Allendorf, and K. L. Knudson. 1983. Devel-
<br />opmental instability as an indicator of the loss of genetic variation
<br />in hatchery trout. Trans. Am. Fish. Soc. 114:230-235.
<br />lister, D. B., D. G. Hickey, and I. Wallace. 1981. Review of the
<br />effects of enhancement strategies on the homing, straying. and
<br />survival of Pacific salmonids, Vol. I. Department of Fisheries and
<br />Oceans, Vancouver. Be.
<br />Mahnken, e. V. W., D. M. Damkaer, and V. G. Wespestad. 1983.
<br />Perspectives of North Pacific salmon sea ranching. Proceedings
<br />Internat!. Fish Farming Conference, Brighton, UK 2:186-216.
<br />Mathews, S. B. 1980. Trends in Puget Sound and Columbia River
<br />coho salmon. Pages 133-145 ill W. J. McNeil and D. C. Him-
<br />sworth, eds. Salmonid ecosystems of the North Pacific. Oregon
<br />State University Press, Corvallis.
<br />Meffe, G. K. 1986. Conservation genetics and the management of
<br />endangered fishes. Fisheries (Bethesda) 11(1):14-23.
<br />Millar, R. B. 1987. Maximum likelihood estimation of mixed stock
<br />fishery composition. Can. J. Fish. Aquat. Sci. 44:583-590.
<br />Milner, G. B., D. J. Teel, E M. Utter, and e. L. Burley. 1981.
<br />Columbia River stock identification study: validation of method.
<br />Annu. Res. Rep. NOAA, NMFS, Northwest and Alaska Fisheries
<br />Center, Seattle, WA.
<br />NWPPC (Northwest Power Planning Council). 1987. Cll1umbia
<br />River basin fish and wildlife program. Portland. OR
<br />Nei, M., and E Tajima. 1981. Genetic drift and estimation of
<br />effective population size. Genetics 98:625-fHO.
<br />Nei, M., and W-H. Li. 1973. Linkage disequilibrium in subdivided
<br />populations. Genetics 75:213-219.
<br />Nevo, E., A. Beiles, and R. Ben-Shlomo. 1984. The evolutionary
<br />significance of genetic diversity: ecological, demographic, and
<br />life history correlates. Pages 12-213 in G. S. Mani. ed. Lect.
<br />Notes Biomath., Vol. 53.
<br />
<br />Fisheries, Vol. 15. No.5
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