Natural Climate Insurance for Pacific Northwest Salmon and Salmon Fisheries: Finding Our Way Through the Entangled Bank

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Natural Climate Insurance for Pacific Northwest Salmon and Salmon Fisheries: Finding Our Way through the Entangled Bank

NATHAN MANTUA1 University of Washington Joint Institute for the Study of the Atmosphere and Oceans/ School of Marine Affairs Climate Impacts Group, Box 354235 Seattle, Washington 98195-4235, USA

ROBERT C. FRANCIS2 University of Washington, School of Aquatic and Fisheries Sciences, Box 355020, Seattle, Washington 8195-5020, USA

Abstract.—This essay focuses on the linkages between climate (variability and change) and sustainable salmon management policies. We show the importance of climate in its effects on salmon production as well as how unpredictable these effects are. Our assessment leads us to conclude that the treatment of environmental uncertainty poses a fundamental conflict between the kind of policies that have been traditionally used in fishery management—basically command and control policies that assume predictability and assert engineering solutions to just one or a few aspects of highly complicated problems—and what the environmental variability dictates—policies that embrace environmental variability and uncertainty and acknowledge a lack of predictability for salmon ecosystems. In this regard, we conclude that three things need to happen in order to integrate climate information into sustainable salmon management policies:

1. De-emphasize the role of preseason run-size predictions in management activities. 2. Emphasize preseason and in-season monitoring of both the resource and its environment. 3. Focus on strategies that minimize the importance of uncertain climate variability and change scenarios to increase the resilience of short and long-term planning decisions.

Our bottom line is that sustainable salmon fisheries cannot be engineered with technological fixes and prediction programs, but that climate insurance for Pacific Northwest salmon can be enhanced by restoring and maintaining healthy, complex, and connected freshwater and estuarine habitat and ensuring adequate spawner escapements. If we are interested in purchasing long-term climate insurance for wild salmon so they can better cope with changing ocean conditions, we will likely get the best return on investments aimed at restoring the health and integrity of our beleaguered watersheds. We also believe that the health of northwest salmon resources is inherently dependent upon social, economic, and political pressures in this world of multi-objective resource conflict. Because of the human dimensions of salmon fisheries, we need salmon fisheries if we hope to sustain wild salmon, and vice versa.

1 E-mail: [email protected] 2 E-mail: [email protected]

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Introduction Prediction and Pacific Northwest salmon and salmon fisheries are Salmon Management in crisis. Federal (U.S.) Endangered Species Act For the past few decades, many salmon fishery man- listings of wild stocks have caused many regional agement agencies have relied on preseason run- fisheries to be virtually shut down. In recent years, size predictions to determine harvest rates and allo- most of the salmon harvested from California to cations between various user groups. Such forecasts Washington were spawned in hatcheries. At the rely on a number of explicit assumptions about same time, the rapid expansion of a global salmon salmon population dynamics. For example, in many aquaculture industry has drastically reduced mar- streams, empirically determined spawner–recruit ket prices for salmon, greatly diminishing the prof- relationships have been used to set escapement goals itability for most salmon fishers. Salmon manage- at the maximum sustained yield (MSY) population ment policies have, for decades, been focused on point (see Ricker 1958). Implicit in deterministic achieving better scientific understanding of fac- stock–recruit concepts like MSY are assumptions tors underlying salmon productivity, then using that environmental change is (a) relatively unim- this knowledge to either forecast yield or engineer portant, (b) unpredictable, and/or (c) difficult to the fish and their habitats to realize consistent translate into the biophysical impacts that ultimately high levels of production. Clearly, these policies alter the spawner–recruit relationship of interest. have failed to sustain fisheries and to sustain wild Yet fisheries scientists have long recognized salmon populations. that some of the errors in deterministic (spawner-, This essay focuses on the role of climate vari- cohort-, and/or smolt-based) run-size predictions ations in salmon fisheries. We discuss the impor- may be explained by environmental changes, and tance of climate in its effects on salmon produc- many have attempted to incorporate environmen- tion as well as how unpredictable these effects are. tal data into such fish prediction models. For exam- Our assessment leads us to conclude that the treat- ple, in the case of Oregon coho, a number of ment of environmental uncertainty poses a funda- researchers have developed statistical models cor- mental conflict between the kind of policies that relating various indices of the marine environment have been traditionally used in fishery manage- with smolt-to-adult return rates (e.g., Nickelson ment—command and control policies—and what the 1986; Lawson 1997; Coronado and Hilborn 1998; environmental variability dictates—what Holling Ryding and Skalski 1999; Cole 2000, Hobday and and Meffe (1995) call “Golden Rule” policies that Boehlert 2001; Koslow et al. 2002; Logerwell et acknowledge a lack of control and predictability al. 2003). There is a growing body of evidence that and aim to facilitate the natural processes thought supports the use of such models, as recent syn- to provide ecosystem resilience. theses of field studies in the northeast Pacific Ocean To develop our argument, we provide a brief have confirmed strong food-web responses to cli- review of state-of-the-art prediction efforts in both mate-related changes in nearshore habitat. These salmon fisheries and climate science, discuss recent biophysical interactions include changes in upper results from selected studies of environmental ocean stratification, nutrient concentrations, phy- impacts on Pacific salmon, describe the nature of toplankton production, zooplankton production human-induced climate change and its potential and community structure, forage fish abundance, impact on Pacific Northwest salmon management as well as the distribution of highly migratory policies, and relate how salmon have evolved diverse pelagics (see Chavez et al. 2002; Mackas and life histories and populations to deal with environ- Galbraith 2002; Pearcy 2002; Peterson et al. 2002; mental variability and uncertainty. We conclude and Chavez et al. 2003; for recent perspectives). the essay by urging a fundamental shift in salmon On the terrestrial side, scientists have long known resource conservation and management efforts that that temperature and stream flow extremes can involves new linkages between science, econom- have a strong bearing on freshwater productivity ics, and policy. for salmonids (e.g., Spence 1995; Bradford and knudsen.qxp 5/27/2004 2:11 PM Page 123

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Irvine 2000). For example, researchers at Wash- and/or cohort returns, are issued prior to harvest ington’s Department of Fish and Wildlife have seasons in order to set harvest rates and determine developed empirically based regression models that allocations. Errors in preseason, run-size forecasts use stream flow indices as predictors for wild coho have been partially attributed to climate and habi- smolt production for several index stocks (Seiler et tat changes, for instance varying ocean condi- al. 2003). tions and ocean carrying capacity like those The whole issue of deterministic prediction is described by Pearcy (1992). Thus, better climate a part of what Holling and Meffe (1995) term “com- predictions offer the promise of reducing some of mand and control” management. The intent is to the preseason run-size forecast errors, at least in define a problem, bound it, and develop a solution cases where the links between climate, environ- for its control. In order to achieve this, policy must ment, and fishery productivity have been quanti- be linked to what Holling (1993) calls “first stream” fied. science—essentially a science that assumes that a The state-of-the-art skill in the science of cli- natural resource system is both knowable and pre- mate prediction rests largely on a demonstrated dictable (see Table 1 for a fuller description of this ability to monitor and predict the status of the linkage of science and policy). tropical El Niño-Southern Oscillation (hereafter simply El Niño). Cane et al. (1986) initiated the Climate Prediction modern era of climate forecasting with a bold model-based forecast for an El Niño event in While it is trivial to predict that winter tempera- 1986–1987 that was essentially correct. Since 1986, tures will be “cold” relative to those in summer in there has been some skill in predicting El Niño at places like the Pacific Northwest, predicting the lead times of one to a few seasons into the future. within and between winter climate variations is Once an El Niño forecast is made, predictions for much more difficult. In some cases, year-to-year climate conditions outside the tropics can easily be variations on the seasonal rhythms of climate are made, though forecast accuracy is always imper- quite large, though rarely as large as the typical sea- fect (e.g., Bengston et al. 1993). During the 1990s, sonal changes. When poor ocean conditions are there were a few notable successes and a few equally blamed for causing problems for salmonids, the tar- notable prediction failures (see below). get of that blame is never the strong and predictable El Niño-based climate predictions are now seasonal climate change but instead it is focused on routinely generated from a variety of sources, rang- the unexpected variations superimposed on the reg- ing from past climate data to the outputs gener- ular seasonal rhythms. Since the late 20th cen- ated with sophisticated computer models. In the tury, governments of many nations have invested early stages of the 1997–1998 El Niño—as early large efforts in predicting this type of climate vari- as June 1997—both approaches were used to make ation, with a special focus on predicting season-to- remarkably accurate forecasts for the 1998 win- season and year-to-year climate changes (NRC 1996). ter and spring climate of North America (see Barn- Much of the climate prediction effort has been ston et al. 1999 and Mason et al. 1999 for reviews motivated by the promise of societal benefits with of climate predictions associated with the extremely an improved forewarning of droughts, floods, or strong 1997/1998 El Niño event). During El Niño climate-related changes in natural resources like and La Niña periods since 1998, climate predic- salmonids or other valuable fish stocks. The idea tions for North America were often skillful, though is simple: better predictions of future climate should not as spectacularly successful, and in some cases lead to better predictions and improved steward- quite inaccurate (for examples, see the NOAA Cli- ship of affected resources. This notion fits very well mate Prediction Center’s web page at with some of the annual activities commonly found http://www.cpc.ncep.noaa.gov). While existing fore- in fishery management agencies. As noted above, cast models have shown impressive skill in predicting the in some regions preseason, run-size forecasts, usu- onset and demise of recent El Niño events, none have ally based on the number of parent spawners, smolts, demonstrated great skill in predicting the magnitude and knudsen.qxp 5/27/2004 2:11 PM Page 124

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reach of tropical El Niño events. However, the com- Climate and Salmon bination of a comprehensive El Niño monitoring system—consisting of real-time buoy, satellite, Because of the never-ending pressures of natural island, and ship observations—along with the 8–14- selection, wild animals have evolved behaviors that month evolution of most events, means that real- allow them to “fit” into their seasonally chang- time monitoring provides continuous updates on ing habitats. For northwest salmonids, aspects of each El Niño event’s progress in ways that can be this evolved behavior include the distinct seasonal used to minimize forecast errors over the course of runs of various stocks of the same and different each event. The multiseason evolution and sophis- species. Thus, the strong seasonal rhythms in the ticated real-time monitoring system for El Niño life history of salmonids can more likely be explained allows resource managers to update their expec- as a consequence of evolution in an environment tations for “El Niño impacts” as the event evolves, with strong seasonal rhythms than as a result of so early forecast errors can be corrected. “climate prediction” by fish. In contrast to the relatively skillful short-term The results of a study by Logerwell et al. (2003) climate predictions described above, climate sci- highlights a few important aspects of the pre- entists have demonstrated no skill in climate dictability of ocean climate variations thought to predictions at lead times longer than 1 year into be important for Oregon hatchery coho salmon the future. In spite of this situation, skillful pre- Oncorhynchus kisutch. Oregon hatchery coho have a dictions at lead times from a few years to a few relatively simple life history, at least in compari- decades into the future may be possible if scien- son to other species and stocks of Pacific salmon. tists decipher the now mysterious processes that In the Pacific Northwest, most hatchery coho adults give rise to multi-year climate variations like those spawn during fall or early winter months. After associated with the Pacific Decadal Oscillation incubation, the eggs hatch into fry that develop as (PDO) (Mantua and Hare 2002). If this happens, freshwater fish for the next year or so. During their appropriate monitoring systems can be designed second spring, hatchery juveniles undergo the smolt- and deployed, and the necessary prediction mod- ing process at which time they are released from els can be developed (NRC 1998). the hatchery and migrate rapidly to sea. Typically, An essential point here is that today’s best cli- Oregon hatchery coho spend about 18 months at mate forecasts are probabilistic in nature. Unlike sea before returning to their natal rivers and/or the case of deterministic salmon run forecasts, hatcheries to spawn as mature 3 year olds. deterministic climate predictions are simply not There is abundant evidence that Pacific salmon, believed to be possible. To the best of our current both of hatchery and natural origins, experience knowledge, future climate is subject to highly large year-to-year and decade-to-decade changes in unpredictable changes because of random events productivity. A 30-year database for Oregon hatch- that we simply cannot foresee. Thus, climate fore- ery coho shows that smolt-to-adult survival rates casts are always presented as changes in the odds in the period 1969–1977 ranged from 3% to 12%, for certain events, making climate forecasting akin while in the period 1991–1998, those rates were to riverboat gambling. Playing roulette, success consistently below 1% (see Figure 1). In periods comes with correctly guessing “red” or “black” like 1969–1977 and 1984–1991, the year-to-year more often than not. Like playing the colors on a changes were also large, ranging from ~2% to 6%. roulette wheel, the science of climate forecasting The extremely low return rates in the 1990s indi- uses an approach that assigns odds for relatively cated in Figure 1 were also observed for many other crude outcomes like “above average temperature” stocks of wild and hatchery salmonids in the north- or “near normal precipitation.” Long-term fore- west. Figure 2 shows observed smolt-to-adult sur- casts that detail the exact amount of snowfall that vival rates for five wild and seven hatchery coho a specific ski resort will get in the coming winter stocks tracked by Washington’s Department of Fish are more likely based on someone’s wishes than on and Wildlife (Seiler et al. 2003). While there is modern scientific methods. clearly a large degree of between-stock variability knudsen.qxp 5/27/2004 2:12 PM Page 125

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Figure 1. Comparison of modeled and observed Oregon Production Index coho smolt-to-adult survival. This simple environmental model uses observed relationships between smolt-to-adult survival and coastal ocean temperatures, coastal sea level, and winds from 1969 to 1998 to translate subsequent environmental conditions into smolt- to-adult survival rate estimates. Estimates for ocean entry years 1999, 2000, and 2001 indicate improved ocean conditions over those observed between 1989 and 1998. See Logerwell et al. 2003 for more details.

at year-to-year time scales, a common feature in Logerwell et al. (2003) developed a rela- eight of these records is decreasing survival trends tively simple model for using physical environ- from the mid-1980s to the early 1990s and sus- mental data to explain past smolt-to-adult survival tained low survival rates for the 1991–1998 period. rates by synthesizing key results of many earlier Hobday and Boehlert (2001) examined smolt-to- studies of coho marine survival and ocean environ- adult return records for dozens of coho hatcheries mental change (e.g., Nickelson 1986; Pearcy 1992; from Vancouver Island to California and the inland Lawson 1997; Coronado and Hilborn 1998; Ryd- waters of the Georgia Strait and Puget Sound. For ing and Skalski 1999; Cole 2000; Koslow et al. these regions, they found evidence for regionally 2002). The model is based on four environmental coherent very low coho survival rates for 1991–1998 indices: (1) the coastal ocean surface temperature smolt releases. In summary, there is compelling in the winter prior to smolt migration; (2) the date evidence for regionally coherent low smolt-to-adult of the Spring Transition, the date at which survival rates, presumably due to inhospitable ocean upwelling-favorable winds are initiated; (3) coastal conditions, for many northwest salmon stocks dur- sea-level during the smolts’ first spring at sea (a ing this dismal production period. proxy for coastal upwelling and alongshore trans- knudsen.qxp 5/27/2004 2:12 PM Page 126

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Figure 2. Observed smolt-to-adult survival rates (SARs) for 12 Washington coho stocks (by ocean entry year). Blue lines indicate observed SARs for the stocks listed in each plot, (W) indicates a wild stock, while (H) indicates a hatchery stock. The red lines (labeled GAM) depict the predicted OPI coho survival rates based on Logerwell et al.’s (2003) simple model that includes environmental conditions in the coastal ocean (repeated from Figure 1).

port); and (4) the coastal ocean surface temperature This model was developed using data from during the maturing coho’s first and only winter 1969 to 1998 and, with observed environmental at sea. Each of the four environmental indices is data, has provided estimates for smolt-to-adult believed to capture different influences on the qual- coho survival for smolts entering the ocean in 1999, ity of the near-surface coastal ocean habitat where 2000, and 2001 (see the *s in Figure 1). Based on juvenile and maturing coho are found. An impor- this model, coastal ocean conditions were much tant finding in this work is that the four differ- improved for Oregon coho smolts in 1999, 2000, ent environmental indices are essentially uncor- and 2001, a result that was generally consistent related with each other. Yet, considering these four with substantial increases in observed smolt-to- environmental indices in sequence yields an envi- adult coho survival rates. Compared to conditions ronmental explanation for most of the ups and in 1991–1998, this improvement in smolt-to- downs in Oregon hatchery coho smolt-to-adult sur- adult return rates is believed to be related to vival rates for the past three decades. food–web changes prompted by significantly cooler knudsen.qxp 5/27/2004 2:12 PM Page 127

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wintertime coastal ocean temperatures, an earlier changes in global energy use patterns and technol- onset of springtime upwelling winds, and more ogy (IPCC 2001). The consequences of the human- upwelling and stronger equator-ward surface caused enhancement of Earth’s natural greenhouse currents in the months of April, May, and June effect are largely unknown; yet, future climate sce- (e.g., see Peterson et al. 2002). narios developed by the Intergovernmental Panel We interpret the results of this modeling work on Climate Change (IPCC) all point to a high like- as evidence that the “ocean conditions” important lihood that climate in the 21st century and beyond for Oregon coho are the net result of sequential tra- will be substantially warmer, and significantly dif- jectories of virtually independent climatic processes. Large- ferent, than any experienced in the past millen- scale climate patterns like El Niño and the PDO are nium (IPCC 2001; NAS 2001). modestly correlated with Oregon’s coastal winter- While there has been some speculation about time SST, yet very poorly correlated with the spring climate change impacts on fisheries, the transla- transition date and springtime coastal sea levels. tion of climate change scenarios into fishery impact This means that knowing El Niño was under- scenarios poses a range of difficult problems. An way in the summer and fall of 2002 provided some impacts assessment methodology in use today is confidence that coastal ocean temperatures during relatively straightforward. Typically, output is the subsequent winter (2002/2003) would likely obtained from a climate simulation model; selected be warmer than average. Yet it provided no clues climate model outputs are then prescribed for a about how early, how strong, or how often the biophysical response model. For example, Welch springtime upwelling winds would blow or what et al. (1998a, 1998b) hypothesized that marine the coastal sea level would be in spring 2003, nor habitat for sockeye salmon Oncorhynchus nerka and would it provide skill for predicting ocean tem- steelhead O. mykiss is defined in part by sharp “ther- peratures in the winter of 2003/2004. mal limits” and that warmer upper ocean temper- If this biophysical model is valid, predictabil- atures in the late 21st century (around the time of ity for ocean conditions important for Oregon coho CO2 doubling) will significantly shrink marine is severely limited. Viewed from another perspec- habitat for these species, as well as displace them tive, it suggests that Oregon coho face a high degree northward into reduced areas in the Bering and of environmental uncertainty every year, at least in Chukchi seas. Likewise, terrestrial temperature terms of ocean conditions (but surely also in terms change scenarios from a suite of climate change of stream and estuary conditions). simulations have been used to estimate changes in stream habitat for salmonids. In one recent study, Climate Change and Salmon projected peak stream temperature changes and known freshwater thermal limits for salmonids There is a growing recognition that, at time frames were used to estimate stream habitat losses in the of a few to many decades into the future, human- western continental United States due to global caused climate change scenarios may provide warming (DFW/NRDC 2002). useful insights into the potential for protecting and Even after such methodologies are applied, the restoring depleted salmon populations. The cul- translation of climate change information into prit behind human-caused climate change has been impacts scenarios carry large uncertainties: in addi- identified: emissions from burning fossil fuels and tion to generally poorly known transfer functions deforestation have substantially increased the atmos- and/or parameterizations in the biophysical mod- pheric concentrations of radiatively important trace els, there are dozens of combinations of emissions gases, the “greenhouse gases.” While it is impos- scenarios and climate models to choose from, with sible to predict future greenhouse gas emissions, little guidance as to which climate scenarios are there is little doubt that greenhouse gas concen- most likely to be realized (Mantua and Mote 2002). trations will continue to rise for at least the next An important message for fishery scientists, managers, few decades and that stabilizing late 21st century and policy-makers is the near consensus in the climate greenhouse gas concentrations at levels two or even research community that the climate of the 20th cen- three times preindustrial levels will require major tury is not likely to provide a good guide for climate of knudsen.qxp 5/27/2004 2:12 PM Page 128

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the near and distant future. A baseline assumption access otherwise unreachable tributary spawning for us, then, is that environmental uncertainty for beds. Seasonal climate and short-term (day-to-day) Pacific salmon will remain large, if not growing, weather variations cause these limiting flow fac- in the remainder of the 21st century. tors to vary sometimes within and sometimes between streams from year-to-year as well. The bot- Life with tom line is that the complex landscape and variety of watersheds in western Washington provide a Environmental Uncertainty diversity of habitats with different environmen- Many scientists have postulated that a diversity of tal sensitivities. Because coho salmon occupy each behaviors and environmental sensitivities serve as of the different habitats, the species as a whole car- evolutionary responses to successful adaptation in ries a diverse portfolio of climate and environmen- uncertain environments (e.g., see ISG 2000). For tal sensitivity, what we like to think of as an evolved example, coastal rockfish have evolved a protracted expression of natural climate insurance. age structure that allows them to weather years of Recent studies have attempted to better under- environmental conditions unfavorable to high pro- stand the temporal and spatial characteristics of duction. Longevity is their adaptive strategy for marine salmon habitat as well. Weitkamp and Neely perpetuation. Pacific hake have evolved the abil- (2002) document the fact that different coho stocks ity to undertake long seasonal migrations, every utilize distinctly different areas in the coastal waters year feeding in one large marine ecosystem (Pacific of the northeast Pacific. Mueter et al. (2002) demon- Northwest coastal ocean) and reproducing in another strate that year-to-year coastal SST and upwelling (the Southern California Bight). Western Alaska wind variations covary at spatial scales of just a few sockeye salmon have evolved very complex popu- hundred kilometers in spring, summer, and fall, lation structures, what Hilborn et al. (2003) call but at much larger spatial scales (1,000–2,500 km) biocomplexity, to maintain their resilience to envi- in winter. Taken together, these studies suggest that ronmental variability and change. different stocks of the same species (in this case, At the metapopulation level, each species of coho) also experience a diversity of marine habitat Pacific salmon exhibits many such risk-spreading at the same time in different places, and at differ- behaviors through a broad diversity of time- ent times in the same places. Just like the case of space habitat use by different stocks and substocks freshwater habitat uncertainty and complexity, of the same species. Lichatowich (1999) put it this prominent characteristics of marine habitat for way: “life history diversity is the salmon’s response salmon are diversity, variability, and unpredictable to the old adage of not putting all one’s eggs in the changes at a broad spectrum of time and space scales. same basket.” In the words of Hilborn et al. “bio- Given the complexity of freshwater salmon complexity of fish [western Alaska sockeye salmon] habitat in western North America and marine habi- stocks is critical for maintaining their resilience to tat in the Pacific Ocean, it seems likely that these environmental change.” examples of complex habitat, variability, environ- Empirical evidence for diverse life history mental sensitivity, and complex salmon stock struc- behaviors and habitat use by salmonids, and their ture are not unique to western Washington coho or close relationship to the physical environment, is western Alaska sockeye salmon. Instead, biocom- found nearly everywhere researchers have looked. plexity in wild Pacific salmon populations appears For instance, studies of natural coho smolt produc- to be more likely the rule than the exception. tion in western Washington yield evidence for a wide variety of stream flow sensitivities in nearby What Does It All Mean watersheds (Seiler et al. 2003). In some systems, for Salmon Policy? wild coho smolt production is limited by high winter flows that scour nests and damage incubating How might an explicit consideration of climate eggs. In other streams, the main limiting factor is and environmental uncertainty aid salmon manage- low summer flows that reduce rearing habitat. In ment efforts? We first review some key characteris- other streams, high fall flows allow spawners to tics of the inseparable linkages between science and knudsen.qxp 5/27/2004 2:12 PM Page 129

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natural resource policy, and then show that, in our long-term survival of salmon in the face of environ- view, the issue of saving wild salmon is insepara- mental change (Hilborn et al. 2003). To sustain bly linked to the issue of saving salmon fisheries. wild salmon in our world of natural resource con- Finally, we offer some specific recommendations of flict is to sustain the direct interaction between what might be done to resolve some existing cli- humans and salmon. For example, in the 1950s, mate-related conflicts between salmon ecology and hydropower interests lobbied for the construction salmon management. of Moran Dam, which would have risen 220 m from Although at times they may seem independ- the bottom of the Fraser River Canyon and blocked ent, in our view, natural resource science and pol- access to 44% of the upriver sockeye spawning icy are inextricably linked. In fact, this is essential grounds. This proposal created a Columbia River- if policy is to be based on scientific assessments and style tradeoff between the choice of industrial devel- analyses. Holling and Meffe (1995) and Holling opment over wild salmon habitat and productivity. (1993) characterize two distinct forms of this link- Fishing interests led fierce political opposition that age, which we summarize in Table 1. The first links eventually halted this project (Meggs 1991). With- “command and control” management with “first out viable fisheries, many Pacific Northwest salmon stream” science. The key underlying assumptions stocks would likely have gone extinct long ago. of both are that relevant aspects of the natural Fisheries generate the social and economic incen- resource system are knowable and predictable and tives that build the political clout needed to pre- that variability can be controlled. Examples of this serve the source of their sustenance. are salmon policies that try to maintain a constant With these management considerations in absolute harvest or constant escapement, or use mind, what should we do? It seems to us that peo- hatcheries to boost fishery production at times of ple now know enough about salmon ecology to low natural production. The second links “golden provide a list of needs for policy makers to develop rule” management with “second stream” science. effective action plans to save threatened wild salmon The assumption here is that relevant aspects of the populations. Key pieces of an effective restora- system are inherently unknowable and unpredictable tion plan should include the following (ISG 2000): and that variability is to be celebrated and pre- served. The golden rule management goal is to • Restrict harvests so adequate numbers of adults facilitate existing natural processes rather than con- can spawn, and avoid harvest policies that trol them. For example, to maintain and restore might alter the life history and/or genetic diver- diverse and connected freshwater and estuarine sity of the spawning population. habitat, to restrict harvest rates to very low levels • Restore diversity by reforming and/or closing to allow as wide a diversity of populations to attain hatcheries to significantly reduce negative adequate spawning escapement, and to time hatch- impacts on wild stocks. ery releases to have minimal direct interactions • Restore and protect habitat, and where neces- with wild populations are all examples of golden sary, remove barriers to fish passage. rule management. • Align economic incentives for salmon fisheries It is our contention that sustainable wild salmon with conservation incentives for preserving populations and sustainable salmon fisheries are wild salmon populations. tightly linked. In our view, one necessary element • Accept variability, environmental uncertainty, for sustainable salmon fisheries is sustainable wild and acknowledge a lack of predictability (cf. salmon populations. While salmon hatcheries now ISG 2000). support the bulk of salmon harvests in the Pacific Northwest, history tells us that hatchery produc- In contrast, current efforts to sustain salmon tion of salmonids is not a sustainable fishery policy fisheries are clearly a matter of often poorly coor- (Lichatowich 1999; Taylor 1999). From an ecolog- dinated politics, economics, law, and ecology. As ical perspective, the genetic and behavioral diver- wild salmon numbers have declined, a combina- sity found in wild salmon populations and absent tion of scientific, political, and socioeconomic in most hatchery populations may be critical for the pressures have led to a slow withering of harvest knudsen.qxp 5/27/2004 2:12 PM Page 130

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opportunities, an increased dependence on hatch- agers to develop better predictive models so har- ery production, and seasons that are ratcheted down vests can be maximized while still offering pro- to smaller and smaller windows of time to protect tection for spawning stocks, a scenario under which endangered wild stocks while still allowing for many wild populations exhibit chronically low harvest opportunities. Policies have generally production (Knudsen 2000). focused on single-species biomass or numbers of In summary, we have seen scientific manage- salmon (e.g., OPI hatchery coho for harvest), rather ment that forces complex and highly variable bio- than considering the ecosystems of which the tar- physical systems to be balanced on a razor’s edge get fish populations are a part. Salmon restoration to satisfy social demands for both extraction and pro- efforts have concentrated on tweaking the status tection of the same resource along with alternative quo, and this has been especially true with efforts uses for critical habitat. As a result, we have devel- to improve fish passage around dams and to reform oped conflicts between those who want to sustain hatcheries. Management agencies have attempted wild salmon populations and those who want to to reduce and/or eliminate variability by using sustain salmon fisheries. Clearly, this has become salmon hatcheries to divorce fish production from a “lose–lose” situation. habitat. Globalized economics have forced har- From this comparison, the main climate com- vested wild salmon to be sucked into an interna- ponent of the conflict between protecting and restor- tional commodity market that is flooded with very ing wild salmon populations and protecting salmon low-price, high volumes of aquaculture salmon, a fisheries lies in the treatment of environmental market reality that most Pacific Northwest salmon variability, and it is in this realm where the poten- fishers are struggling to compete in. Wild salmon tial for policy reform looks greatest. While socioe- markets must be restructured if they are to sur- conomic pressures produce political pressures to vive, perhaps in ways that focus on relatively reduce variability and/or increase predictability so low volumes of high-valued premium quality fish that resource use can be maximized, salmon habi- for domestic and foreign consumption. Such tat and ecosystems contain fundamentally unpre- specialty markets are already developing with brand dictable dynamics (cf. Holling and Meffe 1995) names such as “Copper River Sockeye” and “Yukon (Table 1). Climate enters this picture through its River Kings.” Finally, deterministic and static con- role in providing strong limitations on ecosys- cepts like maximum sustained yield have been tem predictability, a situation that is not likely to used to set harvest goals, pressuring fishery man- change in the future.

Table 1. Key characteristics of linkages between science and natural resource policy, after Holling and Meffe (1995).

First stream Second stream

Science • System knowable and • Ecosystem evolving, has predictable inherent unknowability and unpredictability • Science of parts and • Science of integration disciplines • Seek prediction • Seek understanding

Command and control Golden rule

Policy • Problem perceived, • Retain or restore critical bounded, and solution types and ranges of natural for control developed variations • Objective: reduce • Facilitate existing variability and make processes and variability system more predictable knudsen.qxp 5/27/2004 2:12 PM Page 131

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So how might we better manage our salmon and Washington, where many wild salmon pop- resources if changes in climate, ocean conditions, ulations are severely depleted, harvest managers and salmon populations are so difficult to predict? rely on deterministic and scientifically question- We have three suggestions: able preseason run-size forecasts, difficult to ver- ify assumptions about at-sea distributions of many • De-emphasize preseason run-size predictions. wild and hatchery stocks, and mixed-stock ocean • Emphasize monitoring, including in-season fisheries (SRSRP 2001). It is clear that Alaska’s run-size assessments to guide short-term har- emphasis on monitoring rather than determinis- vest decisions and the development of appro- tic predictions has contributed to the sustainabil- priate real-time environmental measurement ity of Alaska’s wild sockeye salmon fisheries. We systems to gain insights into environmental believe the Alaska approach provides an attractive impacts on stock productivity. alternative to the northwest salmon management’s • Focus on strategies that minimize the impor- continued reliance on deterministic preseason run- tance of uncertain climate variability and size forecasts. change scenarios. A second critical step is to do enough monitoring so that changes in freshwater and marine Now consider these suggestions one at a time. productivity can be tracked and discriminated. First, if predicting the future presents such a dif- Today, only a small number of streams are moni- ficult challenge, it would be wise to distance man- tored for the full life cycle of salmonids (e.g., see agement performance from prediction accuracy. For Seiler et al. 2003). Keeping track of adult spawn- year-to-year management needs, monitoring target ers and estimating harvests allows for a gross esti- stocks and their habitat offers a much more fail-safe mate of productivity. Because marine variability approach than does a continued reliance on highly has strong influences on salmon productivity, it is uncertain predictions. Simple environmental mod- critically important that harvest rates be reduced els like the one used to estimate coho smolt-to-adult in periods of low ocean productivity to allow for survival provide one means for translating the prod- adequate spawner escapements (Knudsen 2002). ucts of environmental monitoring into an estimate A better understanding of changes in marine and for difficult to measure coho survival rates. An even freshwater productivity rests on the establishment better approach would rest on directly monitoring of long-term, continuous records of the age-struc- the target stocks, a daunting task, yet one that ture of spawners, parr, and smolt production, in has received considerable attention in recent research addition to the more commonly collected index projects along the Pacific Coast. If social and polit- counts used to estimate total spawners. A better ical pressures demand preseason predictions, such understanding for existing bottlenecks in wild monitoring-based “forecasts” (using any combi- salmon productivity is also necessary to maximize nation of cohort, smolt, or environmental models) the “bang for each buck” spent on salmon restora- should explicitly acknowledge the large uncertain- tion projects. We realize that monitoring programs ties that exist. Thus, when preseason run-size fore- are expensive and difficult to maintain. However, casts are made, stakeholders and managers should we suggest that at least as much money and effort be presented with a range of possible populations should be spent on monitoring as is already spent to work with, along with some estimate for the on artificial enhancement and short-term engineer- odds of actually witnessing the high, low, and mid- ing fixes (i.e., salmon hatcheries). dle parts of the predicted range. Alaska’s Depart- Finally, for dealing with the uncertainties ment of Fish and Game manages Bristol Bay sock- posed by natural climate variability as well as eye salmon fisheries in precisely this way, annually long-term anthropogenic climate change, the most developing preseason run-size forecasts with explicit conservative and effective long-term strategy is (and often large) uncertainties, along with in-sea- one that minimizes the importance of highly son run-size monitoring and real-time terminal- uncertain climate change scenarios and their atten- area harvest decisions to ensure escapement goals dant impact scenarios for wild salmon. In this are met. On the other hand, in California, Oregon, realm, the critical step is to place a much higher knudsen.qxp 5/27/2004 2:12 PM Page 132

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priority on restoring the natural climate insur- References ance that wild salmon populations must have evolved to survive and thrive in the face of past Barnston, A. G., A. Leetmaa, V. E. Kousky, R. E. environmental changes. We believe that this insur- Livezey, E. A. O’Lenic, H. Van den Dool, A. J. ance is intimately associated with a diversity of Wagner, and D. A. Unger. 1999. NCEP fore- life history behaviors that, in turn, are directly casts of the El Niño of 1997–98 and its U.S. linked to the availability of healthy, complex, and Impacts. Bulletin of the American Meteoro- logical Society 80:1829–1852. connected freshwater habitat. A diversity of fresh- Bengston, L., U. Schlese, E. Roeckner, M. Latif, T. P. water habitat leads to a wide range of seasonal Barnett, and N. E. Graham. 1993. A two-tiered runoff patterns, as well as a wide range of short- approach to long range climate forecasting. Sci- term runoff responses to short-term weather ence 261:1026–1029. and geologic events. Such environmental variabil- Bradford, M. J., and J. R. Irvine. 2000. Land use, cli- ity effectively forces substocks of the same species mate change, and the decline of Thompson River, into different niches and different behaviors British Columbia, coho salmon. Canadian Jour- through the never-ending process of natural selec- nal of Fisheries and Aquatic Sciences 57:13–16. tion. If we are interested in purchasing long-term Cane, M. A., S. E. Zebiak, and S. C. Dolan. 1986. climate insurance for wild salmon so they can bet- Experimental forecasts of El Niño. Nature (Lon- ter cope with changing ocean conditions, we will don) 321:827–832. likely get the best return on investments aimed Chavez, F. P., J. T. Pennington, C. G. Castro, J. P. at restoring the health and integrity of our belea- Ryan, R. P. Michisaki, B. Schlining, P. Walz, K. guered watersheds. If we do this effectively, we R. Buck, A. McFadyen, and C. A. Collins. 2002. might also bring back the resource base required Biological and chemical consequences of the for viable and sustainable salmon fisheries. 1997–1998 El Niño in central California waters. Progress in Oceanography 54:205–232. Chavez, F. P., J. Ryan, S. E. Lluch-Cota, and M. Niquen Acknowledgments C. 2003. From anchovies to sardines and back: While this essay was inspired by a variety of insight- multidecadal change in the Pacific Ocean. Sci- ful commentary on the Pacific Northwest salmon ence 299:217–221. crisis, Jim Lichatowich’s Salmon Without Rivers, Joe- Cole, J. 2000. Coastal sea surface temperature and seph Taylor’s Making Salmon, and Arthur McEvoy’s coho salmon production off the north-west United The Fisherman’s Problem were especially provocative States. Fisheries Oceanography 9:1–16. books that prompted us to consider the broader Coronado, C., and R. Hilborn. 1998. Spatial and tem- aspects of salmon fisheries than those related to the poral factors affecting survival in coho salmon biophysical interactions of climate, environment, (Oncorhynchus kisutch) in the Pacific Northwest. and salmon. Taylor’s (2001) unpublished essay Canadian Journal of Fisheries and Aquatic Sci- ences 55:2067–2077. “Seeking the Entangled Bank: Ecologically and DFW/NRDC (Defenders of Wildlife/National Economically Sustainable Salmon Recovery” pushed Resources Defense Council). 2002. Effects of us to further grapple with the human side of the global warming on trout and salmon habitat in northwest salmon equation. We thank Ed Miles, U.S. streams. Available from the Defenders of Amy Snover, Bill Pearcy, and three anonymous Wildlife, 1101 Fourteenth Street, NW, Suite reviewers for their constructive comments on draft 1400, Washington, D.C. 20005. Available at: versions of this essay. This essay was supported http://www.defenders.org. by collaborations in the University of Washing- Hilborn, R., T. P. Quinn, D. E. Schindler, D. E. ton’s Climate Impacts Group, an interdisciplinary Rogers. 2003. Biocomplexity and fisheries sus- effort within the Joint Institute for the Study of tainability. Proceedings of the National Acad- the Atmosphere and Oceans and School of Marine emy of Sciences 100:6564–6568. Affairs and was funded under NOAA’s cooperative Hobday, A. J., and G. W. Boehlert. 2001. The role agreement #NAI17RJ1232 and The Hayes Cen- of coastal ocean variation in spatial and tempo- ter. This is JISAO contribution #884. ral patterns in survival and size of coho salmon knudsen.qxp 5/27/2004 2:12 PM Page 133

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