NOAA Technical Memorandum NMFS-NWFSC-29 Estuarine and Ocean Survival of Northeastern Pacific Salmon Proceedings of the Workshop March 20-22, 1996 Newport, Oregon Edited by Robert L. Emmett and Michael H. Schiewe National Marine Fisheries Service Northwest Fisheries Science Center Coastal Zone and Estuarine Studies Division 2725 Montlake Blvd. E. Seattle WA 98112-2097 (206) 860-3270 April 1997 U.S. DEPARTMENT OF COMMERCE William Daley, Secretary National Oceanic and Atmospheric Administration D. James Baker, Administrator National Marine Fisheries Service Rolland A. Schmitten, Assistant Administrator for Fisheries

The Northwest Fisheries Science Center of the National Marine Fisheries Service, NOAA, uses the NOAA Technical Memorandum NMFS series to issue informal scientific and technical publications when complete formal review and editorial processing are not appropriate or feasible due to time constraints. Documents published in this series may be referenced in the scientific and technical literature.

The NMFS-NWFSC Technical Memorandum series of the Northwest Fisheries Science Center continues the NMFS-F/NWC series established in 1970 by the Northwest & Alaska Fisheries Science Center, which has since been split into the Northwest Fisheries Science Center and the Alaska Fisheries Science Center. The NMFS-AFSC Technical Memorandum series is now being used by the Alaska Fisheries Science Center.

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This document should be cited as follows:

Emmett, R.L., and M.H. Schiewe (editors). 1997. Estuarine and ocean survival of Northeastern Pacific salmon: Proceedings of the workshop. U.S. Dep. Commer., NOAA Tech. Memo. NMFS-NWFSC-29, 313 p.

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Preface. R.L. Emmett and M.H. Schiewe

Welcome. U. Varanasi

Keynote Address: Salmon Oceanography? W.S. Wooster

Special Topics in Salmonid Life Histories

Interannual Variations in Northeast Pacific Marine Habitats and the Effects on Marine Survival of Salmonids

Decadal Variations in Northeast Pacific Marine Habitats and the Effects on Marine Survival of Salmonids

Process and Mechanisms—Estuarine

Process and Mechanisms—Nearshore Coastal

Process and Mechanisms—Offshore Marine

Working Groups

List of Attendees with Photo

It has been 13 years since the last conference on biotic and abiotic factors affecting oceanic and estuarine survival of salmon. The proceedings from that meeting, "The Influence of Ocean Conditions on the Production of Salmonids in the North Pacific," edited by William Pearcy (1983), summarized existing information linking oceanic conditions and salmonid survival, distribution, and abundance. All four work groups at the 1983 meeting emphasized the need to understand the effects of ocean conditions on salmonid survival, and called for long-term studies of the marine environment.

Unfortunately, the recommendations from the 1983 meeting have gone largely unheeded. Although the salmon research community has continued to spend large amounts of time and funding on freshwater habitat issues, relatively little has been spent on estuarine and marine salmonid habitat issues. In the meantime, Northwest salmon populations have continued to decline, with "poor" ocean conditions often being acknowledged as playing some ill-defined role.

In an effort to once again highlight the importance of estuarine and oceanic residency to salmon survival and year-class strength, we convened a small group in the summer of 1995 to begin planning a workshop to bring together scientists whose research addresses some aspect of this important issue. Providing further impetus to our efforts were several recent reports, including the National Research Council's "Upstream: Salmon and Society in the Pacific Northwest" (1996) and the Snake River Salmon Recovery Team's "Final Recommendations for the National Marine Fisheries Service," which have highlighted the need to fully understand salmonid estuarine and marine life histories—not just because these environments are where salmonids spend most of their lives, but also because substantial mortalities occur there, and rigorous evaluations of freshwater salmonid enhancement projects require information on estuarine and ocean survival.

The workshop consisted of 25 presentations, organized in the following six sessions:

On the final day of the workshop, four working groups were organized to identify and discuss critical research needs, formulate testable hypotheses, and identify potential research strategies to enhance understanding of the role of estuarine and oceanic habitats in salmonid survival. Since the four work groups met independently, their results are presented in slightly different formats.

As with any scientific meeting, the ultimate success depended largely on the thoughtful planning of the steering committee. For the 1996 Newport workshop, "Estuarine and Ocean Survival of Northeast Pacific Salmon," the steering committee was composed of Dr. George Boehlert of NMFS's Southwest Fisheries Science Center, Dr. Robert Francis of the University of Washington, Dr. Steve Ignell of NMFS's Alaska Fisheries Science Center, Dr. William Pearcy of Oregon State University, and Drs. Michael Schiewe and William Peterson, and Mr. Robert Emmett of the Northwest Fisheries Science Center. Drs. William Peterson, Richard Brodeur, Michael Bradford, Colin Levings, Steve Ignell, and Bruce McCain, and Ms. Kate Myers served as chairs and rapporteurs for the working groups. Finally, Ms. Sharon Damkaer and Dr. David Damkaer greatly assisted with compiling, editing, and reviewing the manuscripts in these proceedings.

Although it has taken 13 years to reconvene a conference on oceanic and estuarine survival of salmon, the results perhaps justify the wait. More than 140 scientists, representing disciplines ranging from fisheries ecology to population dynamics, and physical and biological oceanography to climatology, spent three intellectually stimulating days listening to papers, engaging in discussion, and planning future collaborations. To all the participants, we extend our sincere thanks.

Robert L. Emmett and Michael H. Schiewe
Northwest Fisheries Science Center

I take great pleasure in welcoming you to this conference on estuarine and ocean survival of northwestern Pacific salmon. Both the topic of this conference and its location in Newport are very significant to the Northwest Fisheries Science Center (NWFSC). I think most of you know that just a few minutes south of here is the campus of Oregon State University's Hatfield Marine Science Center. The Hatfield Center also houses laboratories of the National Marine Fisheries Service (NMFS), the Environmental Protection Agency, and the Oregon Department of Fish and Wildlife. This setting provides an ideal opportunity to undertake cooperative research programs among the federal, state, and university scientists. We began capitalizing on that potential about a year ago, when we transferred a few of our Seattle researchers to the Newport laboratory. We have also been very fortunate to hire a small number of highly qualified scientists to work on two new research programs at Newport. The first is the west coast groundfish ecology and assessment program. The second is a program to develop research strategies on estuarine and ocean survival of both marine and anadromous fishes.

I am very pleased to be here because this conference allows scientists from different institutions and different disciplines to come together to discuss important issues regarding salmon survival. I think all of you are aware of the national attention focused on the declining salmon stocks in the Pacific Northwest. The salmon problem encompasses the entire West Coast. There is a great deal of concern that we scientists are focusing considerably more attention on certain problems and not enough on others. One of the areas that requires good scientific planning and effort is the understanding of the factors that affect estuarine and ocean survival of salmon.

Salmon, in the course of their natural life cycle, originate in fresh water, pass through estuaries, adapt to salt water, and travel long distances in the ocean before returning to their natal stream to spawn. This life-history strategy is very complex and demanding for the species to maintain, as well as difficult for the scientists to study. The salmon species also has to cope with a number of natural and human-induced habitat changes. When these anthropogenic changes are superimposed on natural upheavals, they cause major impacts on salmon survival. As a result, on the West Coast where environmental and anthropogenic changes have been catastrophic, we are seeing considerable decline in many salmonid populations.

Considering all of the stresses that we are putting on salmon and their habitats, it is amazing that we still have any salmon left. Nevertheless, I believe that with a combination of dedicated scientific effort, wise environmental effort, and good management, we can mitigate at least some of the major stresses that salmon are facing. Most of the attention so far has been on the alterations in fresh water, partly because the changes are much more obvious and easier to study and correct. However, it has become very clear that we need to focus on and develop considerable information about all stages and geographic phases of the salmon life history.

The importance of this information has been emphasized in the Snake River Recovery Team recommendations, in the NMFS-proposed Snake River Salmon Recovery Plan, and in the National Research Council's report. This is the right time for us to come together. I'm very thankful to Mike Schiewe and the steering committee, who have worked for the last 6-8 months to develop this agenda and to bring you all together here. I think it is time for us to identify the areas in which we presently have a lack of information and understanding, and what actions we should undertake collectively for the next few years. So I'm looking forward to your presentations and to the directions for new research that you will recommend. I'm very pleased that NMFS is able to sponsor this conference along with our colleagues at Oregon State University — I am a strong believer in multi-disciplinary efforts to address and develop innovative research strategies.

My own experience as a scientist, working for about 20 years on marine pollution issues, has shown that success has always occurred when scientists from different disciplines come together in somewhat untraditional alliances. I hope that the people who study natural processes, those who study anthropogenic stress, those who study biology, and those who study toxicology can come together. I think this is a good opportunity to develop some innovative strategies and a collaborative plan that we can all pursue for the next few years to come.

Thank you very much.

Usha Varanasi, Ph.D.
Director, Northwest Fisheries Science Center

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