Joe Casola, Climate Impacts Group, University of Washington
Michael Chang, Makah Tribe
Jennifer Cuhaciyan, Bureau of Reclamation
Meghan Dalton, Oregon State University
Scott Lowe, Boise State University
Gary Morishima, Quinault Indian Nation
Philip Mote, Oregon State University
Alexander (Sascha) Petersen, Adaptation International
Gabrielle Roesch-McNally, USDA Forest Service
Emily York, Oregon Health Authority
Beatrice Van Horne, USDA Forest Service, Northwest Climate Hub
Natalie Bennett, Adaptation and Assessment Analyst
Christopher W. Avery, Senior Manager
Susan Aragon-Long, Senior Scientist
<b>May</b>, C., C. Luce, J. Casola, M. Chang, J. Cuhaciyan, M. Dalton, S. Lowe, G. Morishima, P. Mote, A. Petersen, G. Roesch-McNally, and E. York, 2018: Northwest. In <i>Impacts, Risks, and Adaptation in the United States: Fourth National Climate Assessment</i>, Volume II [Reidmiller, D.R., C.W. Avery, D.R. Easterling, K.E. Kunkel, K.L.M. Lewis, T.K. Maycock, and B.C. Stewart (eds.)]. U.S. Global Change Research Program, Washington, DC, USA, pp. 1036–1100. doi: 10.7930/NCA4.2018.CH24
Climate change and extreme events are already endangering the well-being of a wide range of wildlife, fish, and plants, which are intimately tied to tribal subsistence culture and popular outdoor recreation activities. Climate change is projected to continue to have adverse impacts on the regional environment, with implications for the values, identity, heritage, cultures, and quality of life of the region’s diverse population. Adaptation and informed management, especially culturally appropriate strategies, will likely increase the resilience of the region’s natural capital.
Linkage Between Observed Climate and Regional Risks
The intangible values and aspects of the Northwest’s natural environment that support a high quality of life for its residents—wildlife, habitat, and outdoor recreation—are at risk in a changing climate. Tribes and Indigenous communities that rely heavily on the natural environment for their culture and heritage are also at risk.
First Salmon Ceremony of the Lummi Tribe, Washington
Figure 24.6: Tribes in the Northwest typically honor the first salmon caught in the season through Tribal …
The Northwest’s native wildlife is impacted by climate variability and change directly through temperature shifts, water availability, and extreme events, and indirectly through loss or fragmentation of habitat.84 Changes in climate can alter the balance among competing species or predator–prey relationships (e.g., Wenger et al. 201152). Three wildlife categories are of principal concern: already sensitive or endangered species, snow-dependent species, and game species. While the first two groups of animals are generally negatively impacted by changes in climate, some game species, such as deer and elk, may thrive. Game species are of concern not because of their sensitivity to changes in climate and habitat but because of their notable value for recreational hunting and as key cultural resources for tribes. Climate change is also projected to impact First Foods, or foods that tribes have historically cultivated for subsistence, economic, and ceremonial purposes. First Foods vary among tribes but often include berries, roots, water, fish, and local wildlife.85,86 Additionally, nearly half of all adults in the region participated in wildlife-related recreation in 2010.87 As temperatures increase, the demand for warm-weather outdoor and water-based recreation increases, and visitation rates at local, state, and national parks increase.88,89,90 However, boating and other water-based recreation opportunities are likely to decline in the future when summer streamflows and reservoir levels are low. Additionally, popular winter sports and snow-based recreational activities, such as downhill skiing, cross-country skiing, and snowmobiling, have been dramatically impacted by reduced snowfall (see Box 24.7). In low-snowfall years, Washington and Oregon show the highest percentage drop of skier visits, meaning that residents and visitors are losing desirable skiing opportunities.91
Future Climate Change Relevant to Regional Risks
Wildlife responses to a changing climate are varied and complex (Ch. 7: Ecosystems). Some species, such as cavity nesting birds, will very likely benefit from greater disturbance.92,93 Others, particularly snow-dependent species, will likely be unable to persist under climate change.94
Game species are expected to have diverse responses to climate change. Longer dry seasons and more pronounced droughts are projected to reduce wetland habitat extent and duration, causing changes in waterfowl movement. Increased fire disturbance, on the other hand, will likely increase shrub cover, a preferred food for deer and elk;95 reduced winter snowpack may increase food availability in winter; and warmer temperatures reduce winter stress, all of which would support higher deer and elk populations. The primary climate-related impact on game species will likely come from increases in disease and disease-carrying insects and pests.96
Temperature-sensitive bull trout, salmon, and other water-dependent species, such as amphibians, are most vulnerable to increased habitat fragmentation.97,98,99 Increased frequency of extreme events such as flooding, debris flows, and landslides are projected to alter habitats and likely cause local extinctions of aquatic species.
Increased winter streamflow and decreased summer flow are projected to threaten salmon spawning,100 compromising salmon hatchery and reintroduction efforts.101 Projected increases in winter storm intensity will likely lead to higher river flows and increased sediment loading that can bury salmon eggs and reduce salmon survival.101 Rising stream temperatures, ocean acidification, and loss of nearshore and estuarine habitat also increase salmon mortality across all phases of the salmon life cycle.102
Shellfish beds are threatened by sea level rise, storm surge, and ocean acidification.85,103 Species moving out of traditional hunting, gathering, and fishing areas are projected to impact resource access for many tribes.101,104 Increasing wildfire frequency and intensity are changing foraging patterns for elk and deer, and increased prevalence of invasive species and disease will likely diminish both wildlife and foraging for traditional plants, berries, roots, and seeds.105
Razor Clamming in Washington State
Figure 24.7: Razor clamming draws crowds on the coast of Washington State. This popular recreation activity is …
In winter, continued decreases in lower-elevation snowpack are projected to impact snow-based recreation.19 Less snowpack and earlier melting of snowpack will likely result in decreased water availability, reducing the quality, quantity, and availability of water-based recreational opportunities, such as boating, rafting, and fishing.18
Increased wildfire occurrence is projected to degrade air quality and reduce the opportunity for and enjoyment of all outdoor recreation activities, such as camping, biking, hiking, youth sports, and hunting. Degraded air quality also directly impacts human health and quality of life (see Key Message 4).
Wildfires Affect Outdoor Recreation
Figure 24.8: Wildfires impact outdoor wilderness activities and recreation. Reduced air quality and closed trails …
Recreational ocean fishing opportunities are expected to decline under future climate change scenarios,55,56,57 and it is likely that fishery ranges will change.51 Recreational razor clamming on the coast is also expected to decline due to cumulative effects of ocean acidification, harmful algal blooms, higher temperatures, and habitat degradation (see Figure 24.7 and Key Message 1).
Challenges, Opportunities, and Success Stories for Reducing Risk
Historical and projected changes in amenities affecting the quality of life in the Northwest, such as wildlife, recreation opportunities, and edible plants, form a key challenge for managers of these resources. Informed management, however, can reduce the consequences to those who enjoy and value these resources. Sensitive and endangered plant and animal species currently require special management considerations due to historical habitat changes and past species declines. Management of these species can substantially constrain land and water management options, and the protection of these species will likely become more difficult as suitable habitat is lost.
Game species are already managed. Further management of waterfowl habitat is projected to be important to maintain past hunting levels. If deer and elk populations increase, the pressures they place on plant ecosystems (including riparian systems) may benefit from management beyond traditional harvest levels.
The cultural practice of harvesting and consuming First Foods is integral to tribes and Indigenous health (Ch. 15: Tribes).106 Many tribes, such as the Confederated Tribes of the Umatilla Indian Reservation are using climate change vulnerability assessments and climate change adaptation plans to alter how First Foods are managed.107 Tribes can exercise their sovereign rights to manage their resources in a self-determined and culturally appropriate manner, thereby increasing each tribe’s adaptive capacity to respond to climate change impacts on tribal lands, foods, health, and cultures (see Box 24.2).85,108,109 Tribes can also increase their adaptive capacity through regional networks, such as the Columbia River Inter-Tribal Fish Commission, that support tribal and Indigenous planning and management (see Key Message 5).
As fisheries become stressed due to climate change, additional management strategies are likely to be needed to maintain fish populations. Strategies that focus on habitat quality and quantity are likely to be the most successful.110
Some of the species likely to be affected by climate change are already imperiled by population declines, extirpations, or even extinction as a result of historical changes in habitat and other factors. Climate change adds urgency to addressing existing and emergent challenges. Research is already active in identifying resilient habitats (e.g., Morelli et al. 2016, Luce et al. 2014, Isaak et al. 2016114,115,116) and the means for maintaining and improving habitat resilience in the face of increasing climate and disturbance pressure.117 Habitat modeling that includes projections of natural resource shifts, fragmentation, and identification of new wildlife corridors are projected to be beneficial in supporting land and water management decisions that benefit people, recreation, and the Northwest’s varied wildlife.
An institutional network of land, wildlife, and fishery management agencies, tribes, and non-governmental conservation organizations has already successfully reversed negative trends in many fish and wildlife populations caused by other human activities.118 These same groups are exploring methods to improve fish and wildlife resilience in a changing climate. Many habitat improvement activities, a cornerstone of conservation biology, also provide flood mitigation, climate mitigation, adaptation, and ecosystem service co-benefits (Ch. 6: Forests).119,120 Despite proactive management and adaptation, it is likely that species not currently listed as endangered could become endangered over the next century, and eventual extinctions are likely, yet challenging to predict.121
First Foods are an important aspect of tribal and Indigenous health and well-being,122 and they can be used as indicators in tribal health assessments and climate adaptation plans.112,123 The loss or decline of First Foods is projected to have cascading physical and mental health impacts for tribes and Indigenous peoples (see Key Message 5) (see also Ch. 15: Tribes, KM 2).124,125 However, more research to refine these indicators would better support decision-making (see Box 24.2).123,126
Social indicators link a decline in quality of life in the Northwest to loss of recreational opportunities due to climate change impacts,127 but the causal links are not well understood. Additionally, future human migration and population increases may alter the relationship and nature of recreation in the Northwest.128 As the population increases, the demand for snow-based recreation is likely to also increase. However, it is not clear how the limited availability of snow-based recreation (for example, a shorter ski season) in the Northwest over the long term can influence interest in snow sports in contrast to alternatives.