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Developing a Research and Restoration Plan for Arctic-Yukon-Kuskokwim (Western Alaska) Salmon 3 Historical and Recent Arctic-Yukon-Kuskokwim Research This chapter is organized broadly into background information and outstanding questions on the physical environment of Arctic-Yukon-Kuskokwim (AYK) salmon; their population structure and life cycle; their ecological interactions throughout the life cycle; and the human dimension including population trends and resource use, legal and policy analysis, and restoration opportunities. It ends with a discussion of the importance of including traditional ecological knowledge in research on AYK salmon, along with strategies for achieving that goal. We have attempted to identify questions of most interest to scientists and stakeholders. Many of these questions emerged from site visits to AYK communities in 2003 and 2004 and from the workshop held in Anchorage in November 2003. INFLUENCE AND CONSEQUENCES OF CHANGES IN THE PHYSICAL ENVIRONMENT Regional Background Since the 1960s and increasingly in the 1990s and 2000s, dramatic climatic changes have been occurring throughout the range of AYK salmon (BESIS 1997, Hunt et al. 1999, Schumacher and Alexander 1999, SEARCH SSC 2001, Schumacher et al. 2003). Marked changes in the wintertime climate of Alaska and the Bering Sea that occurred in 1976-1977 illustrate the magnitude and nature of some of these changes.
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Developing a Research and Restoration Plan for Arctic-Yukon-Kuskokwim (Western Alaska) Salmon Among the effects documented are a step-like increase of nearly 2°C in air temperature (S.A. Bowling, Geophysical Institute, University of Alaska Fairbanks, personal communication, 1995), an approximate 5% reduction in sea-ice extent (Niebauer 1998), and a decrease in sea-ice thickness (Wadhams 1995). Many local residents around the Bering Sea also noted changes in ice thickness and strength (Huntington 2000). Permafrost temperatures measured in boreholes in northern Alaska are 2-4°C warmer than they were 50-100 years ago (Lachenbruch and Marshall 1986). Discontinuous permafrost (i.e., permafrost that is patchily distributed over the landscape) has warmed considerably and is thawing in some locations (Osterkamp 1994). In addition to the warming trend of air temperatures, marked changes have occurred in atmospheric pressure patterns, circulation, cloudiness, precipitation, and evaporation. Some North American regions are experiencing an increase in runoff (due to increased rain) of major rivers and changes in the time of river-ice breakup and the onset of the summer peak in river flow. In addition, south coastal Alaska glaciers have decreased because of melting, which has increased freshwater discharge rates nearly 15% (Arendt et al. 2002, Royer in press). Multiple air temperature signals exist in the climate record. One signal is a trend to warmer temperatures in recent decades, while many of the other natural patterns have alternating warm/cold periods, such as Arctic Oscillation (AO) and El Niño-Southern Oscillation (ENSO) (NRC 2001, 2003). The environment of AYK salmon is changing, possibly due to warming and associated climate variations that are occurring throughout the Bering Sea and Alaska. This section emphasizes seasonal and longer fluctuations in the air, land, and sea environments. However, we recognize that episodic events can also influence salmon populations. Floods, as extreme hydrological events, can affect water quality and may scour gravels and deposit fine-grained sediment, thereby damaging spawning beds and/or flushing young fish out of the river (Brabets et al. 2000). Three major floods have occurred in the Yukon River basin since 1949 (Brabers et al. 2000): in 1964 (June/July, due to melt of large snow pack), in 1967 (12-18 August, in the middle and lower Tanana River basin with a magnitude estimated to be twice the 100-year flood discharge), and in 1994 (15-27 August, in the upper Koyukuk River basin). At the other extreme are droughts, which can inhibit upstream migration as well as affect eggs after spawning through increased water temperature, decreased concentration of dissolved oxygen, and even dewatering of the redds. Extended droughts also influence groundwater levels that, in turn, decrease the base flow of
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Developing a Research and Restoration Plan for Arctic-Yukon-Kuskokwim (Western Alaska) Salmon streams and springs that are critical salmon habitats. Notable droughts have occurred since 1949 (Brabets et al. 2000): in 1950-1957 (most of the upper Yukon River basin and upper Tanana River basin), in 1969-1970 (western portion of the Yukon River basin, including the Koyukuk River), in 1973-1980 (the most severe period in terms of low flow and length, primarily lower Yukon, Koyukuk, and Tanana rivers), and in 1996-1999 (deficit flows observed at several locations in some of these years on the upper Yukon including Eagle, Nenana, Stevens Village, and above the White River). In general, it appears that spawning habitat in the AYK region has been modified by humans in only a few limited locations, mostly from the effects of placer mining (Knudsen 2003). Other extreme events—for example, volcanic eruptions and earthquakes—can also have a major impact on salmon habitat. Climate and Climate Change Before delving into the impacts climate change may have on AYK salmon populations, we sought to understand what climate change means and to identify factors that cause changes. This allows us to define both the spatial and the temporal scales of climate change and the pathways through which climate change influences biota, and AYK salmon in particular. As defined in a recent National Research Council (NRC) report (2001), “Climate is defined as the average state of the atmosphere and the underlying land and oceans, on time scales of seasons and longer.” This definition is broader than many people consider when they think of climate—that is, the atmosphere only—but it is essential when considering the life and times of salmon. Salmon spawn and develop from egg to smolt stages in the riverine environment before going to sea; therefore, the changing state of all three domains (atmosphere, land, and sea) is crucial to salmon. From a global perspective, the climate is a response to solar and geothermal heating (Woods 1984). Present-day climate on earth is controlled by solar fluxes that in turn affect the temperatures of the ocean and the atmosphere, the hydrologic cycle, and the winds. The major source of heat in the earth’s global heat budget is incoming solar radiation, much of it in the visible wavelengths. Solar energy drives the atmosphere through differential heating that results from changes of heat per unit area with latitude—that is, there are higher rates of heating at low latitudes than at high latitudes. Greater input of solar (shortwave)
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Developing a Research and Restoration Plan for Arctic-Yukon-Kuskokwim (Western Alaska) Salmon radiation occurs at low latitudes, and this excess heat is transported poleward where it is reradiated as infrared (long-wave) energy (NRC 2001). The poleward transport of heat occurs through both oceanic and atmospheric circulation. There is a net heat loss at latitudes above about 38° (Trenberth et al. 1996). This differential heating is augmented by the tilt of the earth’s axis of rotation (the cause of seasonal climate change). It is acted upon by the earth’s rotation to create global pressure differences, and hence wind patterns, which in turn are influenced by regional features—for example, air-sea heat and moisture fluxes. Local features, such as mountain topography, in turn influence the regional atmospheric fields. The winds in these atmospheric systems in turn drive the surface ocean currents, which also transport heat and salt (freshwater). Thus, the two systems are coupled and work together to control the global heat and water budgets. Without the poleward heat transport, the high latitude temperatures would be much lower. Therefore, any processes that affect this transport, either in the ocean or in the atmosphere, will influence the climate. For example, if gases (commonly called “greenhouse” gases, which include CO2 and CH4) that trap energy by absorbing the outgoing long-wave radiation increase, then the result will be changes in atmospheric features and global warming. Changes in cloud cover cause fluctuations in net surface solar radiation and outgoing long-wave radiation. Over the coastal waters where AYK salmon smolts enter the marine environment, latitudinal changes in net radiation could cause differences in smolt and juvenile habitat. Variations in this radiation (mainly the photosynthetically active radiation, or PAR) are a crucial aspect of time-varying forcing for climate and ecosystem change (Foukal 2003). Stabeno et al. 2004 examined net shortwave radiation (NSWR) in the eastern Bering Sea (Figure 3-1). The effect of latitude is evident: the northernmost station received about 21% less energy (W·m−2). The two series from nearly the same latitude appear in phase and of similar magnitude. There are, however, some years (1995, 1999) when they are different by >10 W·m−2, potentially a large enough difference to result in differences in primary/secondary production processes. These within-year differences are likely due to regional differences in cloud cover. The latitudinal differences imply a shorter, more intense period of production over more northern portions of the shelf than exists over the southeastern shelf. This may account for the observed differences in the dominant pathway of carbon cycling on the Bering Sea shelf (pelagic versus benthic); the northern shelf is predomi nantly a benthic system (McRoy 1993), whereas the southeastern shelf
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Developing a Research and Restoration Plan for Arctic-Yukon-Kuskokwim (Western Alaska) Salmon FIGURE 3-1 Daily averaged net shortwave radiation (NSWR) from the National Center for Atmospheric Research/National Center for Environmental Prediction (NCAR/NCEP) reanalysis data: April-June 30 (1972-2001). Minus sign signifies downward flux into the ocean. Source: Stabeno et al. 2004. Reprinted with permission; copyright 2004, John Wiley & Sons. may be either pelagic or benthic, depending on the timing of spring blooms (Walsh and McRoy 1986). The phasing of these two signals could be important to biota in the Gulf of Alaska, North Pacific, and Bering Sea. The sea-surface temperature pattern that the Pacific Decadal Oscillation (PDO) describes has a warm coastal northern North Pacific and cooler central North Pacific. This pattern reverses on interdecadal time scales (20-30 years). At a time when the PDO has a warm phase in the coastal waters, the occurrence of an ENSO event could be especially severe since this also increases the nearshore water temperatures in the Northeast Pacific. The impact of humans on the earth and its climate is marked. How much of the present climate change is natural and how much is human-induced global warming remains a subject of debate. Most scientists agree, however, that the increasing trend in global temperature is due to greater concentrations of human-generated greenhouse gases (AGU Report 1999, IPCC 2001, Levitus et al. 2001), and a crucial point for AYK salmon is that the warming may be amplified in polar regions (Moritz et al. 2002). A recent American Geophysical Union (AGU 2003) position statement on human impacts on climate states, “human activities are increasingly altering Earth’s climate, and natural influences alone do not
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Developing a Research and Restoration Plan for Arctic-Yukon-Kuskokwim (Western Alaska) Salmon explain the increase in global near-surface temperature in the latter half of the 20th century.” The statement further notes that human impacts include air pollution and airborne particle and land alteration in addition to the more commonly recognized increase of atmospheric greenhouse gases. Human impacts interact with natural cycles, likely changing amplitudes and phases and making them less predictable. Pathways from the Physical Environment to Biota Because much of the variability in salmon survival appears to occur within a few months after smolt migration from freshwater to the sea (Pearcy 1992, Downton and Miller 1998, Beamish and Mahnken 2001) and because focusing on this stage may provide predictive modeling (Logerwell et al. 2003), our main focus in this section is the marine environment. To enhance our understanding of the marine ecosystem that the AYK smolts inhabit, we must elucidate processes and mechanisms that transfer changes in atmospheric climate through the ocean to biota. Francis et al. (1998) developed pathways for the Northeast Pacific to identify key elements of ecosystem dynamics. That model was modified by Schumacher et al. (2003) for the eastern Bering Sea to include additional physical features such as sea ice, cloud cover, and precipitation. Our flow model (Figure 3-2) borrows from the latter schematic. Within each of the upper three boxes in the Pathways Model (Figure 3-2) are phenomena and features of the abiotic environment. Depending on location, the general contents of the boxes become more specific. While the Ocean box (Figure 3-2) incorporates both the nearshore zone (depth <10 m) and estuaries, there are processes in these regions that do not exist or are not important in the oceanic domain. In the nearshore zone, littoral drift (which is a form of horizontal current generated by breaking surface waves) is a dominant feature causing erosion and buildup of sediment features. Estuarine circulation, which incorporates horizontal flow and vertical mixing or entrainment of water, is a dominant mechanism generating both horizontal and vertical flow fields within an estuary, but typically it is not a major factor in oceanic circulation. Within the estuary, salinity decreases from oceanic values to near zero. The salinity gradient may influence salmon smolts when they first reach the estuary and also will influence returning adults. Feedback exists between all boxes in Figure 3-2, as suggested by the two-way arrows. For example, water temperature can influence
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Developing a Research and Restoration Plan for Arctic-Yukon-Kuskokwim (Western Alaska) Salmon FIGURE 3-2 Schematic showing pathways through which air-sea interactions flow through the marine ecosystem. Within each box are features and/or processes that affect exchange within and between boxes. The Sea Ice box is seasonal; without ice, the arrows lead to the next box. Source: Schumacher et al. 2003. Reprinted with permission; copyright 2003, Elsevier. AYK salmon both through its impact on the nutrient-phytoplankton-zooplankton sequence (bottom-up), which supplies prey, or by changing the zoogeographical boundaries for predators (top-down) and/or for the salmon themselves. How does phytoplankton influence atmospheric features? Variations within the phytoplankton community can induce intraseasonal fluctuations in sea surface temperature (SST) through regulation of solar radiation penetration due to absorption by chlorophyll and other optically active organic components (Gildor et al. 2003). Variations in SST in turn might affect the flux of heat and moisture into the atmosphere, thereby changing atmospheric features. In the Animals box, for simplicity, we show only a limited set of trophic levels. Humans are
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Developing a Research and Restoration Plan for Arctic-Yukon-Kuskokwim (Western Alaska) Salmon the predator that likely has the greatest impact on AYK salmon, but not explicitly shown as “the” apex predator. For a terrestrial analog to the marine pathways model, the Ocean box would become the River/Terrestrial box and the Sea Ice box would be eliminated. Within the River/Terrestrial box important features would include time of ice cover, ice thickness and breakup, time/magnitude of the freshet, time/magnitude of increased sediment load due to human- or storm-induced erosion, changes in river morphology, and permafrost. Permafrost is defined as any subsurface earth material that remains at or below 0°C continuously for 2 years or more (Nelson 2003), and it represents a complex, integrated response to the energy balance at the earth’s surface (Williams and Smith 1989). Permafrost regions in the Yukon River drainage basin are shrinking due to warming. As this occurs, the frozen soil is transformed into zones that are biogeochemically active. Water flowing through and across these zones is hypothesized to increase the flux of solutes to tributaries and the main stem, ultimately changing the water chemistry of the Yukon River (Schuster et al. 2002). The Chemical & Plants box would include changes in plant communities that are occurring as warming affects the ecosystem. Potential chemical pollutants associated with development of mines and other activities also would be included in this box. Neither of the pathway models includes disease and/or parasites, but to the degree these factors are influenced by the physical (including chemical and geological) environment, they must be considered. Hunt et al. (2002) wove the elements of the marine pathways model together in creating the oscillating control hypothesis (OCH) for the southeastern Bering Sea shelf. As summarized by Stabeno et al. 2004, the OCH relies on a cascade of changes in a given year’s abiotic and biotic features, including sea ice extent/timing, wind-generated turbulence, water column temperature, and timing/magnitude of primary production. In turn, these features impact changes in the abundance of higher trophic levels. The sequence of changes, known as a regime shift, is initiated by atmospheric changes on both interannual and decadal timescales. Changes in the abundance of Bering Sea salmon coincide with regime shifts associated with the PDO (Hare and Mantua 2000). Salmon smolts and juveniles from the Kuskokwim River, and to a lesser degree those from the Yukon River and Norton Sound, likely occur in the waters where dynamics of the OCH apply. In essence, the OCH recognizes that late retreat of sea ice with the attendant low temperatures in the water column and early, short phyto-
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Developing a Research and Restoration Plan for Arctic-Yukon-Kuskokwim (Western Alaska) Salmon plankton blooms are hallmarks of cold regimes. The associated impacts on biota include reduced survival of fish eggs and diminished abundance of zooplankton prey. Under this set of conditions, recruitment of pollock and other fishes will be nominal or weak. Bottom-up processes dictate the flow of energy through the ecosystem during a cold regime. Low water temperatures also can directly affect distributions of some forage fish species. The OCH allows that pinnipeds and piscivorous seabirds may thrive, even under cold conditions, if the population centers of forage fish change, resulting in their becoming more available as prey. During years when sea ice either is not present or retreats before there is sufficient NSWR to initiate a bloom, the spring bloom occurs later than during the cold regime, and water column temperatures are higher. Under this set of conditions, the spring bloom is prolonged and zooplankton production is expected to be high, resulting in readily available prey for larval and juvenile fish, and resultant strong year-classes of pollock and other piscivorous fishes. The OCH accounts for top-down forcing through both cannibalism and other piscivorous fish, which is well recognized in the eastern Being Sea (Livingston and Methot 1998, Livingston et al. 1999). When there is a sequence of warm regime years, recruitment is above average, and the populations of adult predatory fish eventually will increase to a point where the control of future year-class strength is mainly a top-down process. As predation becomes greater, the abundance of young pollock and forage fish declines, and zooplankton become available for other populations (jellyfish, salmon, and baleen whales). In addition, with fewer fishes, declines in populations and/or productivity of pinnipeds and piscivorous seabirds would be expected (Hunt and Stabeno 2002). Features of the Environment of AYK Salmon We begin our discussion of the AYK salmon environments with a discussion of the coupling of the ocean and atmosphere. Patterns in the atmosphere tend to be on hemispheric spatial scales and have temporal variability from years to decades. Variability of atmospheric patterns has profound impacts on marine ecosystems, particularly salmon (Mantua et al. 1997, Downton and Miller 1998, Hare and Mantua 2000, Hollowed et al. 2001), although the mechanisms that link atmosphere-ocean change to biological change are seldom clear.
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Developing a Research and Restoration Plan for Arctic-Yukon-Kuskokwim (Western Alaska) Salmon Important climate signals are evident in atmospheric features of the Bering Sea and continental Alaska, including the AO, ENSO (as mentioned earlier), and the Aleutian low (AL). An oceanic feature closely related to the atmosphere but manifest as a pattern in SST is the PDO. These climate patterns are particularly well-studied for winter. Interest and awareness is growing, however, in climate variations and their importance during warm seasons. While these signals may not be as large as those during winter, they can stand out above background atmospheric conditions (Trenberth et al. 1998), and they can influence the upper ocean and its biota. For example, the unusually high SSTs in the eastern Bering Sea (summer 1997) were ascribed mainly to atmospheric anomalies that occurred concurrently with a strong El Niño (Overland et al. 2001). Marked changes in biota occurred that summer (Vance et al. 1998). The PDO is the leading mode of SST variability in the North Pacific (north of 20°N) and has a dominant timescale of 20-30 years. Although important, the PDO explains only ~21% of the total variance of the monthly SST and is centered primarily on the central North Pacific rather than the Gulf of Alaska and Bering Sea. Signals with other periods, such as decadal, contribute to a lesser extent at times. The ENSO has widespread influence on global climate variability at timescales of 2-7 years. Often, a brief (on the order of months) general warming of the high-latitude North Pacific surface water takes place simultaneously with the ENSO, and a delayed subsurface oceanic warm signal has also been reported (Royer in press). The ENSO has, at times, a small influence (accounting for ~7% of the annual change in sea ice coverage) (Niebauer 1998) on the marine climate of the Bering Sea via atmospheric teleconnections (Niebauer et al. 1999, Hollowed et al. 2001, Overland et al. 2001). Further, the midlatitude decadal variability in the atmosphere can be explained without the ENSO processes (Barnett et al. 1999). The AO represents the leading empirical orthogonal function of the winter sea level pressure (SLP) fields north of 20°N (Wallace 2000). The accompanying time/space patterns in surface air temperature (SAT) closely resemble those in SLP. While the AO is the mode that contains the greatest amount of energy, it accounts for <21% of the total variance in the SLP field. The strongest signal in the AO time series (Figure 3-3) is interannual, but it also contains decadal scale signals, having changed sign in 1976 and again in 1989 (Overland et al. 1999). One way the AO influences the AYK salmon’s environment is through its effect on the
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Developing a Research and Restoration Plan for Arctic-Yukon-Kuskokwim (Western Alaska) Salmon FIGURE 3-3 Time series showing the Arctic oscillation (AO) as surface air temperature (SAT) (upper) and as sea level pressure (SLP) (lower). Applying a running mean to the data (bold line) reveals a decadal signal that is not correlated with sunspots. The warming trend that is marked after the 1960s is likely a result of human-induced global warming. Source: Wallace 2000. Reprinted with permission by the author. AL, which is the monthly or seasonal mean location of the center of low SLP resulting from storm passage typically along the Aleutian Island chain (Schumacher et al. as cited in Allen et al. 1983). The magnitude and position of the AL is a primary factor determining surface winds (advection and mixing of the upper ocean and production/advection of ice), heat fluxes (mixing and ice formation), and precipitation over the Bering Sea, North Pacific Ocean, and Alaska. Indices of atmospheric and oceanic features have been used together with indices of biota to identify abrupt or regime shifts in the ecosystem at decadal timescales (Mantua et al. 1997, Francis et al. 1998, Hollowed et al. 2001). Two regime shifts occurred in the past 30 years: winter 1976-1977, when the PDO and the AO both shifted, and after the winter of 1988-1989, when only the AO shifted (Sugimoto and Tadokoro 1998, Beamish et al. 1999, Hare and Mantua 2000). Some evidence exists that a third shift occurred after the winter of 1998-1999 (Schwing and Moore 2000, Peterson et al. 2002, Peterson and Schwing 2003). These regime shifts often are clearer in biological than in physical time series; salmon production in both Alaska and the Northwest fluctuates with these regime shifts. Several atmospheric and oceanic phenomena influence the habitat for AYK salmon, and the responses in biota are complex. For example, the phas-
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Developing a Research and Restoration Plan for Arctic-Yukon-Kuskokwim (Western Alaska) Salmon addressing stock conservation, addressing customary and traditional subsistence harvest, and protecting habitat. Given the interjurisdictional nature of the law and of responsibilities, independent research such as that by Bader (1998) would be helpful in identifying legal and policy alternatives for the region’s populace, for the resource managers of the region, and for the managers beyond the geographic region whose policies affect AYK regional stocks. With respect to the changing policy and regulation vis a vis subsistence, the database constructed by Andrews et al. (2002) provides a useful beginning for expanded legal research/analysis on state and federal responsibilities for protecting subsistence priority. The committee judges that successful rebuilding of salmon stocks in the region and protecting them for the long term requires a stronger base of scientific information than now exists as well as, and especially in the interim, a thoughtful and conservative policy and regulatory approach. Quality research and analysis of legal, policy, and regulatory alternative approaches and the clarification of responsibilities could be helpful in reaching those mutual goals. Research Questions How are laws translated into regulatory policy, and to what degree do those policies achieve the stated purposes of those laws, with respect to protecting subsistence use, conserving salmon populations, and protecting habitat? How do state and federal responsibilities interact? Under what circumstances do those interactions enhance or hinder achieving policy goals? Are there politically acceptable alternatives that could achieve those legal goals more effectively? RESTORATION Background on Fish Restoration Successes and Failures The committee is reluctant to recommend specific restoration options, except at small scales and locally, because it remains uncertain what the major factors affecting salmon populations are. It is not even certain that the low runs of AYK salmon in the 1990s and early 2000s
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Developing a Research and Restoration Plan for Arctic-Yukon-Kuskokwim (Western Alaska) Salmon represent a long-term decline; it seems equally likely that they reflect regional fluctuations in abundance, perhaps related to environmental fluctuations. Salmon runs in many other parts of Alaska have been high during the period. For example, if a change in ocean carrying capacity has led to a decline in ocean productivity for salmon and hence smaller salmon runs, then restoration activities in streams or reduction in fishing effort are unlikely to be effective. On the other hand, if excess fishing or habitat degradation in freshwater areas have depleted spawning populations or decreased the productivity of streams as rearing areas for salmon, then stream-based restoration activities or a reduction of fishing effort would be more likely to succeed. For this reason, the committee urges that the AYK SSI’s main focus, at least initially, be on funding, conducting, and coordinating research and analyses that can help to better identify the role of major factors affecting salmon abundance in the AYK region and on partitioning their effects into the marine and freshwater environments. Much of the knowledge about salmon developed for Canada, Europe, and the Lower 48 of the United States (NRC 1996, 2004a) is not applicable directly to restoring AYK salmon. Indeed, despite that knowledge, the degree of success that restoration efforts in those places have had is not enormously encouraging, and the most successful efforts have involved habitat restoration, which is not obviously a major issue in the AYK region. Below we discuss some issues that seem relevant to restoration efforts. Hatchery Production Within the AYK Region Within the AYK region, no large hatcheries exist. In Canada’s Yukon Territory, a small mitigation hatchery was built when the Yukon River was dammed at Whitehorse for electrical production. Chinook salmon are collected at the dam and used for broodstock in the hatchery located above the dam. All fish produced (about 250,000 per year) are released into the Yukon system above the hydroelectric dam—at Wolf Creek, Michie Creek, McClintock River, and Byng Creek. Released fish are marked, and when they return to the fishway, they account for 33-50% of the Chinook returning to the fishway (less than 1,000 total return per year of the 30,000 crossing the U.S.-Canada border).
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Developing a Research and Restoration Plan for Arctic-Yukon-Kuskokwim (Western Alaska) Salmon In addition to the hatchery in Whitehorse, in-stream incubation/rearing systems are used for Chinook in the Yukon Territory on the Klondike and Mayo rivers, and McIntyre Creek. In the U.S. section of the Yukon River drainage, periodic small-scale use of incubation boxes has occurred periodically, especially in conjunction with schools, but no substantial effort continues. ADF&G, supported by the Yukon River Drainage Fisheries Association, has a policy to oppose large-scale enhancement hatcheries (designed to create new runs of fish) in the Yukon system. Projects to restore wild stocks and their habitat are supported. In the late 1980s and through much of the 1990s, a small hatchery on the main stem of the Noatak River north of Kotzebue produced chum salmon. That hatchery is no longer in operation. Production Beyond the AYK Region Salmon from the AYK region face competition for food with hatchery fish in the Bering Sea and Gulf of Alaska, as do all wild salmon from both the North American and the Asian sides of the northern Pacific. Hatchery releases of all species of salmon from Alaska and Asia amount to several billion fish per year. Thus, biological competition between AYK salmon and hatchery salmon occurs primarily in the ocean and not within the AYK region. Among commercial salmon fishers, market competition exists. Most market competition covers pen-reared operations worldwide and sea ranching operations. Because subsistence fisheries are often subsidized by commercial fishing operations in the AYK region, this market competition is a concern to both subsistence and commercial fishers. Because industrial scale gold mining occurred in the Yukon Territories for nearly all of the twentieth century, substantial salmon habitat was lost or significantly altered. Under their joint management efforts, both the United States and Canada supported the restoration of habitat for Yukon River salmon. The in-stream incubation and rearing boxes are part of that effort. Research should be undertaken to establish whether this effort is supportive of these joint goals or whether other cost-effective methods of restoration can be identified. Because one-half of all Chinook salmon harvested in the U.S. Yukon system are spawned in Canada, this is important to both partners.
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Developing a Research and Restoration Plan for Arctic-Yukon-Kuskokwim (Western Alaska) Salmon High-Seas Competition Competition between AYK salmon and hatchery salmon at the early ocean life stage appears minimal, because AYK salmon juveniles (ocean age .0) are distributed in waters over the eastern Bering Sea shelf, where they intermingle primarily with other wild stocks of western Alaskan origin. Stock identification research by a variety of methods (tags, fin clips, parasites, otolith marks, scale patterns, and genetics), however, reveals extensive overlap in the ocean distributions of immature (ocean age .1 and older) and maturing Asian and North American hatchery and wild salmon in areas east of 170°E longitude in the central and eastern Bering Sea, Aleutian Islands, and North Pacific Ocean (see INPFC and NPAFC bulletin, technical report, and document series). Because of broad seasonal changes in high-seas salmon distributions, the greatest potential for competition between AYK salmon and Asian hatchery salmon occurs in winter, spring, and early summer in the North Pacific Ocean and in summer and fall in the Bering Sea. The distributions of AYK salmon and North American hatchery salmon overlap most extensively in the Gulf of Alaska, which is a major feeding area throughout the year for all species of western, central, and southeastern Alaska salmon, as well as northward migrating stocks of U.S West Coast (Washington, Oregon, Idaho, and California) and British Columbia salmon. Competition between AYK salmon and hatchery salmon most likely is intense when hatchery releases are large and variations in climate result in poor ocean rearing conditions (Francis and Hare 1994, Gargett 1997, Beamish et al. 1999, Hilborn and Eggers 2000, Volobuev 2000, Levin et al. 2001, Ruggerone et al. 2003). Considerable direct and indirect evidence exists for inter- and intraspecific food competition and density-dependent ocean growth and survival of immature and maturing salmon in the Bering Sea and North Pacific Ocean (Kaeriyama 1989, Ishida et al. 1993, Bigler et al. 1996, Tadokoro et al. 1996, Davis et al. 1998, Helle and Hoffman 1998, Azumaya and Ishida 2000, Walker et al. 2000, Watanabe 2000, Levin et al. 2001, Ruggerone et al. 2003). Direct field research on competition specifically between AYK salmon and hatchery salmon is complicated by the lack of adequate tools to identify the origin of individual fish in mixed-stock samples. Thermal otolith marks are a fast, easy, and relatively inexpensive way to identify hatchery fish (Hagen et al. 1995, Carlson et al. 2000). An increase in the number of duplicate marks released by Asian and North American hatch-
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Developing a Research and Restoration Plan for Arctic-Yukon-Kuskokwim (Western Alaska) Salmon eries, however, has made it impossible to determine the origins of many otolith-marked hatchery fish in Gulf of Alaska samples. NPAFC is attempting to coordinate hatchery salmon otolith marking programs in Asia and North America to reduce or eliminate duplicate marks. In-Stream Incubation Boxes and Small Hatcheries as an Aid to Enhancement The committee heard much interest and concern about the use of either small hatcheries or in-stream incubation boxes to restore and enhance salmon stocks in the AYK region. Other studies, including those conducted by the NRC (1996, 2004a), have looked closely at hatcheries. The conclusions from those reports have been consistent, each noting that hatcheries produce fish that compete with, and often outcompete, wild salmon stocks, whose populations can experience adverse genetic effects. We agree that the risks of large-scale hatchery production, especially in the absence of information about the carrying capacity of the ocean to support the growth of additional young salmon, outweigh the benefits. However, carefully controlled studies of in-stream incubation boxes do not appear to entail significant risk. They could lead to valuable information, as well as perhaps enhancing salmon runs locally. The committee recognizes that stocks in this region are near the northern extreme of the species. With limited data in hand, we believe that marine-derived nutrients are critically important to these streams. Ensuring that adequate fish reach the spawning beds is relevant not only for spawning but also for nutrient supply to other aquatic and terrestrial ecosystems. Research on selected streams, especially those of the northernmost coastal region and of the most upstream regions of the larger rivers, might show that temporary enhancement of those streams would improve the productivity of those streams by jump-starting the nutrient cycle. The committee cautions, however, against human intervention in the long-term selection of parents for the next generation, judging that natural selection of mating pairs on the spawning grounds is an important factor in maintaining both the genetic diversity and the genetic strength of the stocks. A research plan should be developed to investigate the roles of climate change and marine-derived nutrients on AYK salmon stocks and later to study the use of artificial enhancement intervention.
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Developing a Research and Restoration Plan for Arctic-Yukon-Kuskokwim (Western Alaska) Salmon Research Questions How can information needs be prioritized to improve the likely effectiveness of restoration efforts? We have noted the difficulty of advising on a restoration plan for AYK salmon given the lack of confidence about why their numbers declined in the 1990s and early 2000s. If all the research questions in this report were answered, then a restoration plan could be suggested with greater confidence than we have now, but answering all of them would take enormous sums of money and a long time. That is why a prioritization exercise could be helpful. As mentioned earlier, one of the most important general things to do is to partition environmental and human effects on salmon population sizes into freshwater and marine components. At a more specific level, analysis of the existing hatchery and in-stream incubation boxes above Whitehorse on the Yukon and of the recent hatchery experience on the Noatak would provide an important start to this research. What do the data in these locations show? Do controls exist? Did the Noatak hatchery influence relative run strengths of salmon there? Did hatchery and stream boxes on the upper Yukon tributaries influence run strength? INCORPORATING TRADITIONAL KNOWLEDGE AND COMMUNITY INPUT INTO RESEARCH Traditional knowledge and indigenous researchers must be involved at all levels of research within their traditional homelands and on the resources they depend on. Because indigenous people have such an extensive, historical, and indivisible affinity to the land they call home and a fundamental interest in the outcome of all research, they have a much greater need to be involved. Incorporating traditional knowledge into science to answer research questions has not been done to any large extent. However, methods for collecting traditional knowledge have been developed and much information has been collected. As long as people and land continue to be inextricably linked, traditional knowledge will continue to expand. However, the state of experiential land-based traditional learning is in jeopardy in many parts of
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Developing a Research and Restoration Plan for Arctic-Yukon-Kuskokwim (Western Alaska) Salmon Alaska because the linkage between aboriginal people, the environment, and ancestors is weakening. (The connection to the natural environment and land-based traditional learning and retention of the Native language—especially Yup’ik—and culture are currently stronger in the downriver parts of the AYK region than in most other Alaska communities, but the factors that have affected these features operate there as well as elsewhere in Alaska.) Multiple causes have driven these changes, which probably began with the forced removal of indigenous people from the land by mandatory attendance in school and the reduction in size and contiguity of aboriginal homeland through state and federal actions such as statehood, the Alaska Native Claims Settlement Act, and ANILCA. Regulatory management regimes also might have had an effect. These acts of state and federal sovereignty served to assert their claim of ownership of Alaska’s land, reduce tribal members’ status as members of sovereign nations to state-chartered corporate stockholders, and divide the landscape into small checkerboard plots with every other plot owned by different individuals. Finally, these governmental moves served to remove or restrict access to the resources on the land. The primary reason for declining traditional knowledge, closely linked to the land and tribal status changes, is a rapid change from a traditional, land-based lifestyle to a lifestyle detached from the natural environment more dependent on others—for example, grocery stores and governmental programs. Indigenous people have shared traditional knowledge within their own societies and with explorers (new arrivals also) since “the beginning of time.” In North America, this behavior was demonstrated when the American Indians helped the Europeans survive in the new continent. This attitude of cooperation continues today where Alaska Natives provide valuable information to researchers on weather, habitat, and ecological changes and wildlife extinctions. One problem with the current state of knowledge is that most research conducted regarding or including traditional knowledge has been collected, interpreted, and written down from the perspectives of researchers who are not familiar with traditional knowledge. The research techniques might be the current approach for conducting laboratory type research but do not work well with subject matter that is often implicit in nature and contained in people. Anthropologists have long been involved in the collection and interpretation of traditional knowledge. Although traditional knowledge has been incorporated into nearly all fields of research, it is through an-
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Developing a Research and Restoration Plan for Arctic-Yukon-Kuskokwim (Western Alaska) Salmon thropology that we find the most in-depth discussions, study, and acceptance of this concept. ADF&G has been involved in compiling traditional knowledge since the 1980s. Most studies have been conducted through the ADF&G Subsistence Division, focusing primarily on human use of harvested wild resources. To some extent ADF&G has studied community and individual use of salmon in every village on the Yukon River. From the lower Yukon to the Alaska/Canada border, they have documented the use of salmon for dog and human food and identified current usage patterns as well as traditional and changing harvest methods. Additionally, many theses and dissertations have been written, including a variety of salmon traditional knowledge topics. Wildlife researchers have been less inclined to bridge the gap between traditional knowledge and traditional science. They find it difficult to incorporate intergenerational information that has been passed down in a verbally implicit format, because their research system originates from a university-based, scientific-method approach. While numerous traditional knowledge projects are conducted each year, a key thematic problem with the process is that it is difficult for people educated in traditional knowledge to convey their knowledge to those desiring it in a short period of time or within a few lines of text (NRC 2002). Those organizations that require this information should hire permanent staff capable of bridging the gap between the traditional and their specific field of interest. Often, individuals who have not learned ecological or anthropological information in an experiential and verbal manner but have gained their knowledge from institutions are ill-equipped to translate or relate the various fields. Traditional knowledge can provide valuable insight into nearly all fields of scientific endeavor. Clearly, it is an invaluable tool that contributes to the success of scientific research. Traditional knowledge opens a window on a time before the Industrial Revolution became part of everyday life in Alaska. Unfortunately, we continue to lose the eyes (and minds) and knowledge of elders who experienced life before a new lifestyle (post-Industrial Revolution) so radically changed their lives. At present, few remaining elders exist in Alaska who can remember a time when they depended entirely on (and were an integral part of) their natural environment. Therefore, in many cases we are collecting secondhand information, as documented by less vividly detailed results of
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Developing a Research and Restoration Plan for Arctic-Yukon-Kuskokwim (Western Alaska) Salmon current traditional knowledge research projects. While scientists have been standing behind podiums debating the validity and merits of plaiting traditional ecological and traditional scientific knowledge, thousands of volumes of irreplaceable data are forever lost to the grave. This should instill a sense of urgency for the collection and integration of these data before they slip forever into an undocumented past. Most scientific investigations already have limited historical data. The problem of focusing on a single species is illustrated in discussions in this chapter of predator-prey relationships in the AYK region. The most promising development for incorporating traditional knowledge into traditional science has been occurring within the indigenous community. Each year more indigenous researchers graduate college and work in various fields that incorporate their traditional knowledge and their ability to translate it into terms that others can easily understand. Many professional indigenous people working in research-based fields have pursued higher education and research positions because of the appeals of their elders and community leaders who want more informed decision making in areas that affect their lives. The elders’ experiences with academic and government researchers have usually left them feeling uninvolved. Often their information is collected, translated, and placed in a report or book. However, the reasons they participated and the results they hoped for often are not forthcoming. Just as a wildlife biologist, cultural anthropologist, or other scientist would not trust the results of someone not in their field, it is equally troubling to a traditional knowledge holder to have someone seen as an outsider conduct interviews, make conclusions, and write reports that suggest they are a traditional ecological knowledge expert. To generate the best results in any research project one must begin with the most capable researchers. In the area of weaving traditional knowledge and traditional science, one must find a researcher capable of understanding the dynamics of both sides and incorporating the most applicable and useful components of each to answer the question at hand. Finding researchers with these qualifications is not an easy task. However, we must nurture the concept and make it as easy as possible for these types of researchers to become involved. Most of the few researchers who fit this description find themselves in a difficult situation. It is difficult to find work within the indigenous community, but that is where they are needed the most. Traditional knowledge is the very essence of the people who hold that knowledge, and it is often critical to resolving agency questions and problems.
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Developing a Research and Restoration Plan for Arctic-Yukon-Kuskokwim (Western Alaska) Salmon The AYK SSI is itself an excellent example of integrating local communities and Western science. As described in Chapter 1, the SSI is composed of Alaska Native organizations as well as others. Members of those Native organizations, often members of local communities, are playing a major role in developing research questions, making funding recommendations, and engaging Western scientists. They were part of the decision to request help from the National Research Council. Thus, the motivation for the development of the AYK SSI’s Research and Restoration plan is tied to Native culture and the sustainability of salmon. It differs from programs that are generated in the science community and presented to (or even imposed on) local communities. By the same token, the research that the SSI funds will share some of those features. Research Questions How can the loss of vanishing and valuable information be prevented? Organizations like the Arctic Council, Council of Athabascan Tribal Governments, the Alaska Native Knowledge Network, and many others having been striving to conserve traditional knowledge for years. However, while those projects are important, their value and effect will not be completely realized until they are fully integrated into the relevant fields. How can traditional knowledge and traditional science be integrated? Traditional knowledge and Western science are woven together best by someone who has grown up with a traditional indigenous upbringing and then gained an understanding of the scientific method through formal training. This method is better than relying on an outsider to meet, learn about, and build relationships with an indigenous community or to have someone raised within an indigenous community attempting to apply the scientific method without the proper training. It is much easier—challenging though it might be—for a nonscientist to learn the methods of science than it is for someone from outside the Alaska Native culture to learn the Natives’ way of knowing. It is necessary to identify and encourage indigenous and collaborative research projects that weave traditional science and traditional knowledge with Western science, including the consolidation of salmon research into a library, including geographic information system data. How can local communities be involved in scientific research? Information should flow bi-directionally. The entire population
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Developing a Research and Restoration Plan for Arctic-Yukon-Kuskokwim (Western Alaska) Salmon from elders to schoolchildren should be represented where appropriate. One possibility would be the involvement of school students in marine science activities, as for example is being done at Little Diomede, Alaska (K. Frost, ADF&G, personal communication, August 2001). The committee was impressed by the enthusiasm shown about being involved by students at places it visited, in particular at Unalakleet, where it met in the school’s facilities. In addition, asking this question leads to additional more detailed questions, such as the following: What communities are associated with which spawning and rearing areas for AYK Chinook stocks? What communities are associated with which spawning and rearing areas for AYK summer chum stocks? What communities are associated with spawning and rearing areas for AYK fall chum stocks? This last question also requires a list of spawning and rearing areas and communities, which also are basic research questions. What types of local habitat manipulation by communities would improve the survival of eggs, fry, and smolts in their associated spawning and rearing areas (such as live boxes, beaver dam management, woody debris, and predator fish management)? What monitoring program can be implemented to measure the success of egg, fry, and smolt survival at this local level? What types of genetic or biological markers can be used to identify fish from these local stocks?
Representative terms from entire chapter: