Salmon smolts prior to hatchery release.

The MSI Program conducts a variety of research projects designed to help evaluate hatchery-wild stock interactions. An estimated 25 billion juvenile salmon enter waters of the North Pacific Ocean and adjacent seas annually and up to one fourth of these originate from hatcheries. In turn, each year some 300-500 million returning adult salmon are caught in commercial fisheries with several million others caught in recreational and subsistence fisheries. In some regions, over half of returning salmon are derived from hatcheries. Therefore, hatcheries and enhancement become important issues in marine ecosystem studies and in international treaties and accords involving Pacific salmon.

Ester Lake Hatchery in Prince William Sound.

With upwards of 1.0 million metric tons of adults harvested each year, current salmon production in North Pacific Ocean waters is near all-time record levels, in spite of runs depressed or endangered stocks in some regions. One-fourth of this production comes from hatcheries and many questions arise about potential adverse interactions between wild and hatchery fish. Areas of concern include genetic dilution from hatchery strays, over-harvesting of weak wild stocks while targeting hatchery fish, inbreeding or outbreeding depression, domestication, and loss of fitness due to hatchery breeding programs. Other issues include potential competition for food or habitat between wild and hatchery fish in estuarine and other marine waters.

Alaska hatcheries included rigorous policies for genetics and fish health, restrictive broodstock programs, and careful siting of hatcheries designed to conserve and protect the integrity of wild stocks. For example most Alaska hatcheries are at or near tidewater on non-anadromous water sources, not on rivers with major runs of wild salmon. Alaska hatcheries are designed to supplement depressed fisheries, not to help rebuild or interact directly with depressed wild stocks. The MSI Program works cooperatively with several production hatcheries in Alaska to help minimize hatchery-wild stock interactions.

Contact:
Bill Heard
Auke Bay Laboratories
Alaska Fisheries Science Center, NOAA Fisheries

Ted Stevens Marine Research Institute
17109 Pt Lena Loop Rd
Juneau, AK 99801
(907) 789–6003
Bill.Heard@noaa.gov

Some related reports and publications

• Wertheimer, A. C., W. R. Heard, and W. W. Smoker. 2004. Effects of hatchery releases and environmental variation on wild-stock productivity: Consequences for sea ranching of pink salmon in Prince William Sound, Alaska, p. 307-326. In K. M. Leber, S. Kitada, T. Svasand, and H. L. Blankenship (editors), Stock enhancement and sea ranching 2. Blackwell Science Ltd., Oxford.
• Orsi, J.A., A. C. Wertheimer, M. V. Sturdevant, E. A. Fergusson, D. G. Mortensen, and B.L Wing. 2004. Juvenile chum salmon consumption of zooplankton in marine waters of southeastern Alaska: a bioenergetics approach to implications of hatchery stock interaction. Rev. Fish. Biol. and Fisheries 14: 335-359.
• Heard, W. R. 2003. Alaska salmon enhancement: a successful program for hatchery and wild stocks, p. 149-169. In Y. Nakamura, J. P. McVey, S. Fox, K. Churchill, C. Neidig, and K. Leber (editors), Ecology of aquaculture species and enhancement of stocks, Proceedings of the 30th U. S.-Japan Aquaculture Panel, 3-4 December 2001. Florida Sea Grant TP-128, Mote Marine Lab, Sarasota, FL.