The last time I was in Newport, in 1983, was for a workshop on the influence of ocean conditions on the production of salmonids in the North Pacific. It arose from the idea that the environment in which salmon spend their oceanic years had some important effect on their survival and growth. At the time, we thought that interannual variability was the most important frequency—hence our book from a preceding workshop on nonsalmonid species was called From Year to Year. But since then, as today's lectures have made clear, many have come to believe that longer scales, decadal and beyond, are probably more important.
The preface to the 1983 salmon workshop report speaks of the devastating effects of the 1982-83 Niño event on ocean catches of coho and chinook salmon (Oncorhynchus kisutch and O. tshawytscha) off Oregon and Washington. More recently, I have even heard El Niño described as a "catastrophe." Like hurricanes and earthquakes perhaps, El Niño is only a catastrophe to the extent that it negatively affects humans. Otherwise, it is a particular feature of natural variability and may be as beneficial as it is harmful to the marine ecosystems that it influences. For example, salmon biologists have been forced since 1983 to contemplate the medium in which their favorite fish spend a critical part of their life history. Of course, that has not been sufficient to turn all salmon biologists into fishery oceanographers overnight.
When I came to the University of Washington (UW) nearly 20 years ago, I almost fell into the chasm that lay between Fisheries and Oceanography. It was my impression then that the College of Fisheries was interested mostly in salmon and oysters—not a bad combination if you are hungry, but not really representative of the broad scope of contemporary fishery problems. There was little interaction with the Department of Oceanography, which stood aloof from such messy problems. In contrast, I had spent much of my career at an institution on the edge of a pelagic realm, where interactions between fish and their environment were accepted as an article of faith, at least after Harold Sverdrup and Elton Sette had cooked up what became CalCOFI (California Cooperative Oceanic Fisheries Investigations), a program in which fishery scientists and oceanographers have comfortably cohabited for nearly 50 years.
Of course, there can be too much of a good thing. El Niño has become a convenient deus ex machina for all sorts of unexplained events, a curious viewpoint for those who normally see all stock variations as caused by man. In 1982-83, I was asked what El Niño would mean for salmon returns—I ventured a guess that the effect would be similar to that of the 1957-58 event, but I was left with the impression that no one had paid much attention to that. I tend to see El Niño not as some sort of plague but rather as an important climatic signal that arises in the equatorial Pacific Ocean and sometimes extends into the subarctic Pacific, even into the Bering Sea, and in extra-tropical latitudes is usually associated with decreased upwelling, warming, and deeper thermoclines. These in turn influence primary and secondary production, distribution of both plankton and nekton, and growth and mortality of higher level carnivores, including salmon.
But El Niño is not the only influence on these factors, and in the case of fish that are harvested, the effects of fishing, not only on target stocks, but on their prey, predators, and competitors, have also to be taken into account. It is my impression that no one really understands how changes, however induced, in one important component of an oceanic ecosystem trickle down or bubble up to affect other components. The question comes to a head in what has been called the carrying capacity problem.
With the increase in the number and output of salmon hatcheries around the North Pacific rim, and with the observation of reduced growth (smaller size at age) of returning salmon, the question arises, "Is there a finite carrying capacity for salmon (and other high trophic level, pelagic carnivores) in the subarctic Pacific, and is it in danger of being exceeded?" A related question concerns whether carrying capacity is a constant, as tends to be assumed in the case of marine mammals, or whether it changes in response to climate variations. These questions led PICES (an international North Pacific organization comprising Canada, China, Japan, Korea, Russia, and the United States), in 1993, to initiate development of a GLOBEC program on Climate Change and Carrying Capacity, the so-called CCCC (four Cs) program.
From the beginning, considerable controversy arose over the definition of the term "carrying capacity." For purists, it was "k" in the exponential growth curve, what I call the "bugs in a bottle" approach, and could not be extended to ecosystems. Much of the thinking on these matters comes from terrestrial or other enclosed systems (e.g., lakes) and does not fit relatively open-ended systems such as those in the ocean. The debates led ultimately to a definition that I, at least, am comfortable with: "Carrying capacity for a given population is considered to be the limiting size of that population that can be supported by an ecosystem over a period of time and under a given set of environmental conditions."
The carrying capacity problem is a subset of a grander scientific question: "How are marine ecosystems of the subarctic Pacific Ocean affected over periods of months to centuries by changes in the physical environment, by interactions among components of the ecosystems, and by human activities?"
So how do you study such a vast problem? People find it difficult to think freely about this question because of the funding situations in which scientists here and in most other countries find themselves. Thinking is constrained by the perception that only limited resources are available to support such studies. Without new funding, the only solution is to reprogram existing funds, a prospect that strikes terror into most bureaucracies and causes them to develop elaborate defensive strategies. While some coastal programs are already funded and under way, studies of the open subarctic Pacific Ocean, the main feeding ground for most salmon stocks, are much more difficult both to design and to fund.
Two relatively inexpensive approaches are probably the ways to begin, retrospective studies and modeling/theoretical studies. These are needed both to frame hypotheses and to design process studies and monitoring efforts. PICES is holding a CCCC Workshop on Conceptual/Theoretical Studies and Model Development in Nemuro, Hokkaido on 23-28 June 1996 and is convening a one-day symposium on Methods and Findings of Retrospective Analyses at its Fifth Annual Meeting in Nanaimo, British Columbia in October. PICES has a Working Group on Monitoring the Subarctic Pacific Ocean and a Technical Committee on Data Exchange—these will also support the CCCC program. The other desideratum at this early stage is a network of committees and study groups in which scientists participate in planning in a systematic way, achieving some sort of coordination among the different national GLOBEC and GLOBEC-like programs.
Development of an effective scientific program is colored by fishery politics, in the United States (Alaska vs. the rest of the country) and internationally. Salmon politics seem to be particularly virulent. In some countries, fishery agencies take the view that all research on salmon and ecologically related species—that is, everything else—is their exclusive property. Perhaps in those countries, fishery science is intimately linked with the other disciplines necessary for ecosystem studies—meteorology and climatology, oceanography of the several flavors (physical, chemical, biological), and ecology in the broader sense—but I have not seen any evidence of such a happy interdisciplinary, interinstitutional marriage there nor in most other countries. Yet it seems to me that without such a broad approach, the scientific questions that underlie those of more immediate interest to management are unlikely to be resolved.
Of course this tension goes beyond any single country. Many here work for government agencies charged with managing fisheries or with providing the scientific assessments used by the managers. Some such people tend to follow the accepted population dynamics paradigms and to be impatient with those who are more free to challenge them and to pursue other approaches without the day-to-day responsibilities of management. I remember hearing the director of one fisheries center refer to those in what I thought of as a particularly productive and insightful research group as "playing in an intellectual sandbox." I spoke earlier of the ancient schism between oceanographers and fishery scientists, and my experience at UW shows that the chasm remains despite more bridges across and more student interest in crossing those bridges.
I hope we can emerge from this workshop with the conviction that the scientific questions relating salmon growth and survival to oceanic and estuarine conditions are important to oceanographers as well as to fishery scientists, and that study of these questions calls for a full sharing of ideas and joint action among those who can bring their knowledge and skills to all facets of the question. Perhaps then we will be ready to celebrate the development of a field that might reasonably be called "salmon oceanography."