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SUB-SECTION CLIMATE CHANGE TAB 2

Climate Change And Our Natural Resources

A Report from the Treaty Tribes in Western Washington

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Climate Change and

Our Natural Resources

A Report from the Treaty Tribes in

Western Washington

Front cover images (Top left, clockwise):

Mary Leitka, Hoh tribal member, bundles cedar bark for use in weaving baskets; Quinault tribal fisherman Sam Goodman works his fishing

net on the Quinault River early in the blueback, or sockeye, fishing season; the Pacific Ocean. Photos: Debbie Preston, NWIFC. Adult chum.

Photo: Fran Wilshusen, NWIFC.

Climate Change and Our Natural Resources

TABLE OF CONTENTS

Principal Message....................................................................................................................................................................iv

Executive Summary...................................................................................................................................................................v

Introduction.......................................................................................................................................................................v

Climate Change Impacts to Tribal Rights and Resources...........................................................................................................v

Global Warming and Regional Climate Change.....................................................................................................................vi

Moving Forward................................................................................................................................................................vi

1. Introduction..........................................................................................................................................................................1

2. The Treaty Tribes and Our Homelands......................................................................................................................................1

2.1 Physical Setting.............................................................................................................................................................1

2.2 Ecological Setting........................................................................................................................................................ 3

2.3 The Changing Landscape............................................................................................................................................. 3

2.4 Tribal Sovereignty and Treaty Rights................................................................................................................................ 4

3. Global Warming and Climate Change..................................................................................................................................... 5

3.1 Observations of a Warming World.................................................................................................................................. 5

3.2 Pacific Northwest Climate Trends................................................................................................................................... 6

3.3 Regional Climate Projections......................................................................................................................................... 6

3.4 Overview of Implications for Treaty-Protected Resources................................................................................................... 7

4. Freshwater Aquatic Environments........................................................................................................................................... 8

4.1 Chapter Summary......................................................................................................................................................... 8

4.2 People of the Salmon................................................................................................................................................... 8

4.3 Snowpack and Glaciers................................................................................................................................................ 9

4.4 Stream Temperatures................................................................................................................................................... 11

4.5 Streamflow Patterns.....................................................................................................................................................12

Taking Action: Jamestown S’Klallam Tribe’s Strategy for Dungeness River Floodplain Protection and Restoration..............................16

4.6 Sediment in Streams....................................................................................................................................................17

4.7 Freshwater Wetlands...................................................................................................................................................18

4.8 Resilience in Freshwater Environments...........................................................................................................................19

Taking Action: Nooksack Indian Tribe Climate Change Research..............................................................................................21

5. Coastal and Marine Environments........................................................................................................................................ 22

5.1 Chapter Summary....................................................................................................................................................... 22

5.2 When the Tide is Out, the Table is Set........................................................................................................................... 22

5.3 Ocean Temperatures.................................................................................................................................................. 22

5.4 Sea Level Rise............................................................................................................................................................ 25

Taking Action: Storm Surge at the Quinault Indian Nation Village of Taholah............................................................................. 28

5.5 Ocean Acidification.................................................................................................................................................... 29

Taking Action: Makah Tribe Ocean Acidification Research.......................................................................................................31

5.6 Coastal Hypoxia........................................................................................................................................................ 32

5.7 Resilience in Coastal and Marine Environments.............................................................................................................. 32

Taking Action: Lummi Nation Wetland and Habitat Mitigation Bank........................................................................................ 34

6. Terrestrial and Upland Environments..................................................................................................................................... 35

6.1 Chapter Summary....................................................................................................................................................... 35

6.2 The Tree of Life........................................................................................................................................................... 35

6.3 Shifts in Vegetation Ranges.......................................................................................................................................... 37

6.4 Shifts in Wildlife Ranges.............................................................................................................................................. 38

6.5 Productivity and Phenology......................................................................................................................................... 39

6.6 Wildfire.................................................................................................................................................................... 39

6.7 Disease and Pests....................................................................................................................................................... 40

A Report from the Treaty Tribes in Western Washington

TABLE OF CONTENTS (CONT.)

6.8 Landslides and Mass Movement....................................................................................................................................41

6.9 Resilience in Terrestrial Environments.............................................................................................................................41

Taking Action: Swinomish Indian Tribal Community Forest Resilience........................................................................................ 42

7. Impacts Across the Landscape.............................................................................................................................................. 43

7.1 Chapter Summary....................................................................................................................................................... 43

7.2 Interactions with Existing Ecological Stressors................................................................................................................ 43

Taking Action: Tulalip Tribes' Conference for Regulatory Harmonization................................................................................... 44

7.3 Invasive Species......................................................................................................................................................... 45

7.4 Tribal Community Well-Being and Infrastructure.............................................................................................................. 45

Taking Action: Swinomish Climate Change Initiative.............................................................................................................. 46

8. Moving Forward: Adaptation and Opportunities.................................................................................................................... 47

8.1 Chapter Summary....................................................................................................................................................... 47

8.2 Climate Change Adaptation........................................................................................................................................ 47

Taking Action: Stillaguamish Tribe Floodplain Protection........................................................................................................ 50

8.3 Traditional Knowledge and Principles of Environmental Stewardship..................................................................................51

8.4 Reducing Greenhouse Gas Emissions........................................................................................................................... 52

Taking Action: Lummi Nation Energy Efficiency and Clean Energy............................................................................................ 54

8.5 Next Steps and Research Needs.................................................................................................................................. 55

Taking Action: Suquamish Tribe Developing a Zooplankton Imaging System............................................................................. 58

9. Conclusions...................................................................................................................................................................... 59

10. Report Contributors and Acknowledgments......................................................................................................................... 59

11. Citations.......................................................................................................................................................................... 60

APPENDICES

Appendix A: Selected References ......................................................................................................................................... 90

Appendix B: Glossary of Terms ............................................................................................................................................. 93

Appendix C: Common and Scientific Names of Species .......................................................................................................... 98

Appendix D: An Overview of Climate Models ....................................................................................................................... 102

Appendix E: Climate Change Response Strategies ................................................................................................................ 105

Appendix F: Tribal Climate Change Studies .......................................................................................................................... 112

Appendix Citations .......................................................................................................................................................... 114

FIGURES

Figure 1: Climate Change Impacts and Treaty-Protected Resources................................................................................................ix

Figure 2: The 20 member tribes of the NWIFC in western Washington...........................................................................................2

Figure 3: Photographs of Anderson Glacier show its significant retreat in the 20th century. The arrows mark the edges of the glacier in

1936 in both images. Source: ONP 2015 (1936: Asahel Curtis, 2004: Matt Hoffman, Portland State Univ.)......................................... 10

Climate Change and Our Natural Resources

Figure 4: Average summer temperatures and salmon thresholds as observed in the 1980s (left) and projected for the 2040s under a

moderate GHG emission scenario (right). The dots represent water temperature monitoring sites and the continuous color represents air

temperatures. Source: Mantua et al. 2010.................................................................................................................................. 12

Figure 5: Egg-to-migrant survival for juvenile chinook in the Stillaguamish River under a range of annual peak flow magnitudes. Source:

Stillaguamish Tribe of Indians.................................................................................................................................................... 13

Figure 6: Typical hydrological regimes of PNW rivers showing representative peak and base flow timing in rain-dominated, transient

snow (or rain- and snow-dominated), and snow-dominated watersheds. Source: after Elsner et al. 2010............................................ 14

Figure 7: Streamflow changes in the Quinault River during the 20th century. Projections for the 2040s show a shift from two periods of

high flows to one. The 2040s curve is shaded to represent a range across a number of different climate scenarios. Source: University of

Washington Climate Impacts Group cited in USGCRP 2009......................................................................................................... 15

Figure 8: The contemporary floodplain of the lower 2.8 miles of the Dungeness River covers 169 acres (shown in blue), whereas the pre1963 floodplain extended over 730 acres (shown in black). Source: Jamestown S'Klallam Tribe ........................................................ 16

Figure 9: Percent of the upper 100 m of the water column off the U.S. Pacific coast estimated to be undersaturated with aragonite (a

form of calcium carbonate used by marine organisms to form shells): during pre-industrial times (left) and in August to September 2011

(right). Numbers in the squares denote pteropod monitoring stations. Source: modified from Bendaršek et al. 2014........................... 30

Figure 10: California mussel samples were collected from three locations: (1) Wa’adah Island; (2) Tatoosh Island; and (3) Strawberry

Rock. These locations represent the different environmental conditions where mussels grow in Neah Bay. Source: Makah Tribe............ 31

Figure 11: Change in areas of Washington where the climate will be suitable for Douglas fir by the 2060s. The map colors indicate

the percentage of statistical models that suggest the climate will support Douglas fir, so orange areas are at greatest risk while dark

green areas are at the lowest risk. Note that the decline is centered at lower elevations and that in western Washington decline is most

widespread in the south Puget Sound region and the southern Olympic Mountains. Source: Littell et al. 2010.................................... 38

Figure 12: Annual peak streamflow for the North Fork Stillaguamish River near Arlington, WA, from 1928 to 2015 (USGS Gauge

12167000). Although peak flows show wide interannual variation, the trendline (R=0.27) indicates an overall increase in annual peak

flows over time.......................................................................................................................................................................50

Figure 13: Air temperature changes projected for the end of the 21st century for four GHG emissions scenarios: very low (top left), low (top

right), moderate (bottom left), and high (bottom right). For an explanation of the scenarios, see Appendix D. Source: IPCC 2014..............53

TABLES

Table 1: Observed relative mean sea level (MSL) trends in Washington. Since tide gauge measurements are made with respect to a local

fixed reference level on land, these measurements record relative MSL trends that combine the rates of global sea level rise and local

vertical land motion. Source: NOAA (2013) and Craig (1993, for Olympia)..................................................................................... 26

Table 2: Comparison of sea level rise projections for Washington state relative to 2000.................................................................. 27

APPENDIX FIGURES

Figure A-1: A comparison of SRES and RCP scenarios for annual carbon emissions (top) and the resulting temperature change (bottom).

For temperature, the lines represent the central estimate and the shaded area represents the likely range. Source: adapted from Melillo et

al. 2014 with data from CMIP3 and CMIP5.9............................................................................................................................. 103

A Report from the Treaty Tribes in Western Washington

iii

PRINCIPAL MESSAGE

This report from the twenty member tribes of the Northwest Indian Fisheries Commission focuses on the impacts of climate

change to our homelands, waters, and ways of life. We have a historical and contemporary relationship with the watersheds

and ecosystems of the Pacific Ocean coast, the Strait of Juan de Fuca, Hood Canal, and Puget Sound. Virtually all of the

resources and activities that our treaties protect—fishing, gathering, and hunting—are impacted by the effects of climate

change. In this report, we present our collective concerns and an overview on the regional scale of changes in natural

systems and the challenges we face:

·· Interference or reduction in opportunities to exercise our treaty rights as resources decline, disappear, or are pushed

out of our traditional fishing, hunting, and gathering areas due to changing environmental conditions;

·· Loss of important cultural sites and infrastructure to substantial physical disturbance; and

·· Negative societal outcomes due to the direct effects of climate change and the indirect effects on cultural continuity

and community cohesion.

Each tribe is unique in its culture, geography, and priorities in response to climate change. Each tribe is conducting scientific

research to assess impacts to the species and ecosystems of greatest concern. As individual tribes and in collaboration with

our tribal and non-tribal partners, we are bolstering the resilience of natural systems and our communities to adapt to change.

Climate Change and Our Natural Resources

EXECUTIVE SUMMARY

INTRODUCTION

Our ancestral territories stretch from the Cascade Mountains westward to the Pacific Ocean. They encompass diverse

sub-regions with distinct ecosystems that face both shared and unique challenges in the face of climate change. A wide

variety of plants and animals have sustained our communities for thousands of years, providing food, fuel, shelter, medicines,

and materials for commerce. Our natural resources form the foundation for our spiritual life, sacred ceremonies, and

community cohesion.

In the last 150 years our homelands and waters have profoundly changed. Salmon and steelhead runs that are central to our

culture and economy are at a fraction of their historical populations.1 Many lowland old-growth forests have been logged.2

In some parts of the region, natural shorelines have been replaced by concrete3 and hundreds of acres of shellfish beds are

too polluted for harvest.4 These changes have contributed to declines in natural resources important to our communities.5

Today climate change is affecting our environment and the natural resources we depend upon in countless ways. This report

focuses on climate impacts to the ecosystems that play central roles in our cultures, health, identity, and lifeways. It also

introduces a selection of potential responses and adaptation strategies.

CLIMATE CHANGE IMPACTS TO TRIBAL RIGHTS AND RESOURCES

In the 1850s, we entered into treaties with the U.S. government. In exchange for ceding vast tracts of land, the tribes

retained the right to fish, hunt, and gather as we have always done throughout our traditional territories. Major federal court

decisions have upheld our treaty rights as the law of the land.6 The ability to exercise our rights is diminished if species

productivity drops too low or if species are no longer available in our gathering, hunting, and fishing grounds.

Individual species will respond to climate change depending on their characteristics and the local conditions. A detailed

analysis of the response of each species that is important to each tribe is beyond the scope of this report. Nonetheless, there

are overarching concerns that have the potential to challenge our ability to exercise our treaty-reserved rights. An overview

of potential threats to treaty-protected resources associated with climate change is as follows:

Declining runs of salmon and steelhead due to changes in streamflow, stream temperature, levels of dissolved

oxygen, amount of sediment in streams, susceptibility to disease, ocean temperatures, ocean chemistry, timing of prey

availability, prey type, and competition from warm-water species.7

Migration of marine fish away from historical fishing grounds as they seek out cooler ocean temperatures.8

Replacement of traditional fish runs with invasive species and new species that have migrated from the south.9

Declining populations of shellfish (both mollusks and crustaceans) due to changing ocean chemistry.10

Closing of shellfish harvest areas due to harmful algal blooms.11

Loss of traditional shellfish harvesting areas, forage fish spawning grounds, and important cultural sites to

sea level rise or increased coastal erosion.12

Loss of water supplies for drinking and other needs due to saltwater intrusion from sea level rise, or changes to

precipitation, streamflow, and/or groundwater availability.13

Declining populations of wildlife and birds due to habitat changes, loss of food sources, disease, and competition

with invasive species.14

Migration of wild game and birds out of traditional hunting grounds as they move farther north or to higher elevations.15

Decreased plant productivity and shifts in species ranges due to heat stress, drought, invasive species

encroachment, or increasing pests.16

Loss of traditional hunting grounds, plant gathering areas, and sacred sites due to wildfire, landslides,

or invasive species.17

Loss of access routes to important cultural sites due to flooding, bridge damage, permanent road closures,

or landslides.18

A Report from the Treaty Tribes in Western Washington

Changes in the timing of key life stages in a variety of species, such as the migration of salmon, fruiting of berries,

or optimal time to harvest cedar bark.19

Negative health outcomes from poor air quality, heat stress, spread of diseases, loss of nutrition from traditional foods,

and loss of opportunities to engage in traditional cultural activities.20

GLOBAL WARMING AND REGIONAL CLIMATE CHANGE

Global warming is the increase in global average temperatures that has been recorded around the world. Rising temperatures

cause changes to long-term patterns and variability of climate factors such as wind, humidity, and the type and amount

of precipitation.21 The dominant driver is the human-caused buildup of greenhouse gases such as carbon dioxide (CO2),

methane, and other heat-trapping gases in the atmosphere, largely due to burning fossil fuels and changing land use.22

The impacts of climate change are already happening. These impacts are projected to continue or accelerate into the future.

In the Pacific Northwest (PNW), the observed and projected trends in physical systems include the following:

·· Warmer air temperatures;23

·· Shrinking glaciers;24

·· Less snowfall;25

·· Decreasing summer streamflows;26

·· Increasing winter peak flows;27

·· Changes to timing of peak and base flows;28

·· Higher stream and lake temperatures;29

·· Lower levels of dissolved oxygen in streams;30

·· More sediment delivered into, carried by, and deposited in streams;31

·· Drying out of wetlands;32

·· Increased frequency and size of wildfires;33

·· Greater probability of landslides;34

·· Warmer ocean temperatures;35

·· Rising sea levels;36

·· Stronger storms and greater storm surge;37 and

·· Changing ocean chemistry, including ocean acidification.38

Figure 1 (on page ix) illustrates the relationships among the primary changes to physical systems in our region and the types

of treaty resources affected by those changes.

MOVING FORWARD

The combination of direct habitat alteration and global climate change creates a challenge for tribes in maintaining tribal

lifeways and inherent sovereign rights. Tribal leaders and communities face difficult decisions in order to sustain the species

and ecosystems that form the basis of our treaty rights, and to maintain our livelihoods, feed our families, and pass on our

culture in the face of ongoing environmental changes.

Climate change programs that work toward sustaining tribal treaty rights and resources call for the following:

·· Development of tribal capacity to assess on- and off-reservation climate change impacts and to promote resilience to

these impacts at multiple scales.

·· Management of natural resources using practices that incorporate climate change impacts into long-term plans.

·· Coordination between tribes and among departments within each tribe, such as natural resources, planning, public

health, emergency management, and community outreach.

·· Partnerships between tribal and non-tribal scientists on research, modeling, and tracking environmental trends.

Climate Change and Our Natural Resources

·· Partnerships with federal, state, and local governments to work together on local concerns and solutions.

·· Access to funding sources that assist in the implementation of adaptation projects that protect tribal people,

homelands, and resources.

Moving forward entails efforts on two fronts. The first focuses on the reduction of harmful greenhouse gas emissions at local,

regional, national, and international levels in order to prevent the worst-case scenarios of climate change impacts from

occurring. Around the world, indigenous communities are promoting renewable energy sources, better energy efficiency,

and the choice to leave fossil fuels in the ground.39 The second type of effort enhances the ability of ecosystems and the

communities that rely on them to adapt to changing conditions. Strategies the tribes are using to foster ecosystem resilience

to environmental change center on the following:

·· Developing approaches to natural resources management that include innovative solutions and consider landscapescale processes;

·· Working together to restore natural physical processes and ecological function, and to reduce existing stressors,

such as water quality impairment, fish-passage barriers, noxious invasive weeds, and habitat fragmentation;

·· Promoting biological diversity, protecting intact ecosystems, and creating climate refuges—areas where changes

are expected to be less severe or to occur more slowly;

·· Tracking changes to local environmental conditions, including the use of tribal traditional knowledge of climate

patterns and ecosystems as a source for early warning signals;

·· Promoting cultural resilience through tribal citizen engagement and education, especially K-12 education; and

·· Sharing knowledge and expertise with tribes and non-tribal entities within and outside of the PNW.

A Report from the Treaty Tribes in Western Washington

vii

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viii

Climate Change and Our Natural Resources

A Report from the Treaty Tribes in Western Washington

Fish

Shellﬁsh

Plants

Decreased

Low Flows

Snowpack &

Glacier Loss

Less

Groundwater

Less

Dissolved

Oxygen

Stream

Warming

Fish

Shellﬁsh

Increased

Aquatic

Disease

Fish

Shellﬁsh

Freshwater

Acidiﬁcation

Wildlife

Plants

Increased

Peak Flows

Fish

Shellﬁsh

More Fine

Sediment,

Channel Erosion,

& Aggradation

Streamﬂow

Changing

Precipitation

Patterns

Air Temperature

Warming

Increased CO2 &

Greenhouse Gases

in the Atmosphere

More River

Flooding

Sea Level

Rise

Fish

Shellﬁsh

Wildlife

Plants

More Harmful

Algal Blooms

Ocean

Warming

Fish

Shellﬁsh

Wildlife

Less Ocean

Dissolved

Oxygen

Fish

Shellﬁsh

Treaty-Protected Resource

Terrestrial Process

Ocean Process

Freshwater Process

Atmospheric Process

Illustration: Eliza Ghitis, Northwest Indian Fisheries Commission

Coastal

Flooding

& Erosion

Fish

Shellﬁsh

Wildlife

Plants

Increased Pests

& Disease

Ice Sheet

Melt

Ocean

Acidiﬁcation

Wildlife

Plants

Larger, More

Frequent

Wildﬁres

Increased

Drought

Wildlife

Plants

Figure 1: Climate Change Impacts and Treaty-Protected Resources

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Climate Change and Our Natural Resources

1. INTRODUCTION

This report from the treaty tribes in western Washington

presents a synthesis of the impacts of climate change to the

natural systems that sustain our treaty rights. Species of great

importance, including fish, shellfish, terrestrial plants, and

wildlife, are already facing negative effects due to climate

change. These species provide food security and ensure

economic survival for tribal families. They also form the

foundation for our spiritual life, sacred ceremonies, traditional

medicine, and community cohesion. Human activities, both

past and present, have degraded ecosystem function in many

areas. Our ability to protect and restore natural ecosystem

function is threatened by climate change.

The document begins with background information on the

treaty tribes in western Washington and our homelands

(Chapter 2). After an overview of global and regional climate

trends (Chapter 3), Chapters 4 through 7 describe existing

and projected climate change impacts to aquatic, marine,

and terrestrial environments. Also presented in these chapters

is a brief summary and a discussion of factors that contribute

to resilience, or the ability to adapt to change. Chapter

8 describes potential next steps for moving forward and

presents a collection of research questions for consideration.

The report concludes with a series of appendices that contain

additional information and resources. Throughout this

document, sections labeled Taking Action present examples

of individual tribes taking action to understand or address the

impacts of climate change to treaty-protected resources.

Many species are important to our communities, and a

complete accounting of the climate change impacts and

biological response of each one is beyond the scope of

this report. Instead, we present an overview of our greatest

common concerns on the regional scale. The information

presented here is a synthesis of a number of notable studies

that describe the impacts and future projections of climate

change in the Pacific Northwest (PNW) and the implications

for biological communities. This report presents a snapshot

for this moment in time, but new information about climate

change and the subsequent biological responses continues

to emerge. For further reading, see Appendix A: Selected

References. Additional explanations of terms used in this

report can be found in Appendix B: Glossary of Terms.

A Report from the Treaty Tribes in Western Washington

2. THE TREATYTRIBES AND

OUR HOMELANDS

The scope of this impact assessment covers the area

of interest to the 20 member tribes of the Northwest

Indian Fisheries Commission (NWIFC). This geographical

area includes the reservations, trust lands, traditional

territories, Usual and Accustomed (U&A) places, and

historic hunting and gathering areas of the member tribes:

·· Hoh Tribe

·· Jamestown S’Klallam Tribe

·· Lower Elwha Klallam Tribe

·· Lummi Nation

·· Makah Tribe

·· Muckleshoot Indian Tribe

·· Nisqually Indian Tribe

·· Nooksack Indian Tribe

·· Port Gamble S’Klallam Tribe

·· Puyallup Tribe of Indians

·· Quileute Tribe

·· Quinault Indian Nation

·· Sauk-Suiattle Indian Tribe

·· Skokomish Indian Tribe

·· Squaxin Island Tribe

·· Stillaguamish Tribe of Indians

·· Suquamish Tribe

·· Swinomish Indian Tribal Community

·· Tulalip Tribes

·· Upper Skagit Indian Tribe

Additional regional tribal consortiums are actively

involved in this area: the Point No Point Treaty Council

and the Skagit River System Cooperative.

2.1

PHYSICAL SETTING

Our homelands extend from the Cascade Mountains

westward to several miles off the Pacific coast of

Washington (Figure 2). They encompass the watersheds

of four different saltwater bodies: Puget Sound, Hood

Canal, the Strait of Juan de Fuca, and the Pacific Ocean,

each with distinct ecosystems and unique problems in

the face of climate change. Over the course of millions

of years, tectonic forces have given rise to the Olympic

and Cascade mountains and the complex topography

of the region. A sequence of Ice Age glaciations over

the last 2 million years blanketed the region in ice. In the

most recent glaciation, continental ice sheets spread

from the north into the Puget lowlands and portions of

the Olympic Peninsula, as far south as the area around

present-day Centralia. At the peak of this glacial episode,

the ice over what is now Seattle was 3,000 feet thick, and

nearly 6,000 feet thick over present-day Bellingham.40

Along with carving out many of the topographic features

visible today, the ice also deposited vast amounts of clay,

sand, gravel, and boulders. The last glaciation ended about

10,000 to 12,000 years ago, leaving glaciers to persist only

in the high mountains of the Olympics and Cascades. During

the last glaciation, sea levels were hundreds of feet lower than

they are today. Over the course of thousands of years, the

melting ice sheets released the water that had been locked up

back to the world’s oceans. Sea levels in our region have been

relatively stable for about 6,000 years.

Figure 2: The 20 member tribes of the NWIFC in western Washington. Map: Ron McFarlane, NWIFC.

Climate Change and Our Natural Resources

Today the climate of the region is temperate, with relatively

cool, dry summers and wet winters that are mild at low

elevations. The elevation of this area ranges from sea level

to over 14,000 feet. The great variety of topographic relief

causes temperature and precipitation to vary between and

within each watershed. The average maximum temperature

in July ranges from 65°F near the Pacific coast to 80°F in the

Cascade Mountain foothills. Average minimum temperatures

in January range from 20°F at higher elevations to 38°F along

the Pacific coast. Precipitation ranges from 24 inches per year

to over 120 inches per year in the mountains. In general, most

precipitation occurs between October and March and this

wet period has a dominant influence on the hydrology of

the region.

2.2

ECOLOGICAL SETTING

The ecosystems of western Washington support a wide variety

of plant and animal species that we have always depended on

for food, medicine, tools, crafts, ceremony, and commercial

endeavors. Some of the common plants and animal species

that we use are listed below. For the scientific names of

these and other species mentioned in this report, please see

Appendix C: Common and Scientific Names of Species.

·· Salmonid fish species including chinook salmon

(both fall and spring/summer runs), sockeye salmon

(including lake-based kokanee), chum salmon, pink

salmon, coho salmon, steelhead/rainbow trout,

cutthroat trout, bull trout, and Dolly Varden trout.

·· Other finfish species including Pacific herring, sand

lance, surf smelt, sardines, Northern anchovy, hooligan

(also called eulachon or smelt), mackerel, Pacific

halibut, black cod (sablefish), Pacific cod, Pacific

whiting, lingcod, Pacific lamprey, sturgeon, flatfish,

rockfish, grunters, sculpins, and many others.

·· Mollusks such as native Olympia and introduced

Pacific oysters, butter clam, Manila clam, razor clam,

horse clam, littleneck clam, California mussel, blue

mussel, geoduck, rock scallop, pinto abalone, and

gumboot chiton.

·· Crustaceans such as Dungeness crab, shrimp, spot

prawn, crawfish, and barnacle.

·· Other marine organisms including Pacific octopus,

squid, sea urchin, anemone, sea star, sea cucumber,

eelgrass, seaweed, and kelp.

·· Culturally important marine mammals, such as gray

whales, orcas, harbor seals, and northern fur seals.

A Report from the Treaty Tribes in Western Washington

·· Terrestrial mammals and birds such as elk, deer,

mountain goat, black bear, cougar, river otter,

beaver, fisher, snowshoe hare, turkey, and

various waterfowl.

·· Tree species for traditional and commercial

uses include western red cedar, yellow cedar,

Douglas fir, lodgepole pine, western hemlock,

silver fir, western white pine, Sitka spruce, red

alder, black cottonwood, and big leaf maple.

·· Many types of plants and fungi used for food,

tools, baskets, nets, medicines, cultural

ceremonies, and other traditional practices.

Examples include camas root, nodding onion,

skunk cabbage, oceanspray, Pacific ninebark,

bear grass, and various berries, nuts, herbs,

ferns, lichen, and mushrooms.

2.3

THE CHANGING LANDSCAPE

In the last 150 years, the landscapes of western

Washington have undergone significant changes.

Early settlers from Europe and the East Coast of the

United States put pressure on traditional fishing grounds

while early logging activities reduced hunting grounds

and profoundly changed watershed structures and

functions. Habitat was lost and degraded as land

was cleared for railroads, agriculture, and residential

development. With these endeavors came many

ecosystem modifications that continue to this day,

including the draining and filling of salt marshes and

wetlands; the construction of dams, levees, and

revetments; installation of shoreline and stream bank

armoring; the straightening and diversion of streams;

the removal of downed wood and logjams from streams,

the logging of old-growth forests; and the introduction

of paved surfaces on prairies and meadows.

Since 1889, Washington state has lost 70 percent

of the estuarine wetlands, 50 percent of the

riparian habitat, and 90 percent of the old-growth

forest.41 In Puget Sound, only 31 percent of the

approximately 2,470 miles of shoreline has not

been modified in some way. The freshwater

tidal and brackish marshes of Puget Sound have

seen a loss of 93 percent—in the Duwamish and

Puyallup rivers nearly all of this type of habitat has

disappeared.42 In Grays Harbor on the Pacific coast,

37 percent of the shorelines were modified.43

Climate change impacts are occurring within the context

of landscape modification that has already degraded

function in many ecosystems within our homelands. In

some cases, existing impacts compound the negative

effects of climate change. For an overview of the ways

climate change interacts with landscape modification,

please see Section 7.2: Interactions with Existing

Ecological Stressors.

and unclaimed lands” for hunting and gathering.44 The

rights secured by the treaties are the supreme law of the

land, as established by Article VI Section 2 of the U.S.

Constitution, and have been consistently upheld by federal

courts. These rights cannot be legally curtailed by blocking

access nor by undermining the viability of species through

habitat destruction. The treaties also do not have any species

limitations. We retained the right to harvest any species

whether or not they were harvested historically.45

2.4

Today, tribes provide leadership and participate in nearly all

aspects of natural resources management in our region. Tribal

leaders and communities face difficult decisions in order to:

TRIBAL SOVEREIGNTYAND

TREATY RIGHTS

The impacts of climate change to our natural resources

create a challenge for maintaining our treaty rights. When

the tribes in what is now known as western Washington

ceded vast tracts of our lands in treaties with the United

States government in the 1850s, we reserved certain

rights to protect our way of life. The treaties specifically

and purposefully protected our ability to continue to

gather, hunt, and fish on the reservations and outside

the reservations—the areas referred to as “usual and

accustomed places” for aquatic animal life and “open

·· Sustain the species that form the basis of our

treaty rights;

·· Support species and habitat adaptation to

ongoing changes to air, land, and water; and

·· Maintain our livelihoods, feed our families, and

pass on our culture in the face of environmental

loss and change.

Climate Change and Our Natural Resources

3. GLOBAL WARMING AND

CLIMATE CHANGE

Around the globe, the burning of fossil fuels, deforestation,

cement production, wetland conversion, raising livestock,

and other human activities have added greenhouse gases

(GHGs) into the atmosphere, leading to warming of the air

and oceans. Carbon dioxide (CO2) is the dominant GHG

emitted by human activities, but methane is also a potent

GHG, along with nitrous oxide and sulfur hexafluoride.

The number of CO2 molecules in the atmosphere has risen

from 280 parts per million (ppm) during the Industrial

Revolution to around 400 ppm today.46 The current CO2

levels are higher than they have been in 800,000 years and

likely the highest they have been in the past 20 million years,

based on the geological record.47

The National Academies of Science states that

“Climate change is occurring, is caused largely by

human activities, and poses significant risks for—and

in many cases is already affecting—a broad range of

human and natural systems.”48

3.1

OBSERVATIONS OF A

WARMING WORLD

Global warming is the increase in global average temperatures

in the air and oceans. It contributes to the suite of effects known

as climate change. Climate change refers to a significant shift

in long-term patterns and variability of climate factors such

as temperature, precipitation, humidity, and wind over the

course of decades, centuries, or millennia. The science of

global warming is well established, as confirmed by data from

multiple independent sources around the world.49 Both direct

observations since the 1950s and climate reconstructions from

the geological record unequivocally point to changes in the

climate system over the last century.50 Many of the impacts

described in the chapters below for the PNW region have also

been observed globally. The effects of a changing climate are

seen in global ocean temperatures, sea levels, air temperatures,

and changing patterns of atmospheric circulation.51 The CO2

in the atmosphere is dissolving into the world’s oceans and

changing the chemistry of sea water.52

The year 2015 was the warmest on record since 1880, by

the largest margin ever recorded, according to two separate

analyses of global climate data by the National Oceanic and

A Report from the Treaty Tribes in Western Washington

Atmospheric Administration (NOAA) and the National

Aeronautics and Space Administration (NASA). The 16

warmest years on record have occurred since 1998 and

15 of the 16 warmest years on record have occurred since

2001.53 The Intergovernmental Panel on Climate Change

(IPCC) Fifth Assessment Report (AR5) states that global

averages of land and ocean surface temperatures from

multiple datasets show an increase of 1.5°F (0.85°C)

between 1880 and 2012, with an increase of about 1.0°F

(0.6°C) occurring in the last three decades.54 The majority

of the observed warming since the 1950s is due to human

activities.55 While a warming of 1.5°F may not seem like

much, the geological record shows that average global

temperatures have been stable over long time periods.

Even seemingly small shifts in global average temperature

correlate to major environmental changes. For example,

at the end of the last ice age that covered our region in

thousands of feet of ice, the average global temperatures in

the low mid-latitudes were 7 to 11°F colder than today.56

While the planet has been warming steadily over time,

climate variability can alter the rate of warming for a period

of years to decades. Climate variability is an inherent

characteristic of the climate system due to the variable

nature of interactions between the components (such as

the ocean and atmosphere), and variations in external

forcing, both natural (such as solar radiation) and humancaused (such as GHGs).57 Variability in the climate and

the random patterns inherent in atmospheric circulation

will continue in the future. These factors contribute to

uncertainty in climate projections for temperature and

precipitation in North America, especially at middle

and high latitudes during winter.58 In addition, climate

change will not occur evenly or at the same rate across the

landscape. Some climate types will disappear while new

types emerge. The rate of change in climate variables will

vary across systems and different locations.59

The IPCC AR5 confirmed a number of the projections

presented in previous assessments.60 For example, the

first IPCC assessment in 1990 projected that higher

global temperatures would result in more extreme

weather events, in part stemming from changes to the

hydrologic cycle with variable effects across the globe.

Although extreme events have multiple causes, climate

change has played a role in the increasing frequency and

intensity of heavy precipitation events, droughts, heat

waves, and extreme cold events.61 In 2013, 41 separate

weather disasters across the world each caused more

than $1 billion in damages.62 In 2014, the United States

alone experienced 8 weather and climate disaster events

that individually exceeded $1 billion in losses. Overall

they caused 377 deaths and $110 billion in damages.63

In addition, many previously predicted impacts are

happening sooner and more quickly than expected,

such as sea level rise and the melting of the Greenland

and Antarctic ice sheets.64 More information on global

impacts can be found in Appendix A: Selected References.

For more details on the processes involved in global

and regional climate projections, see Appendix D: An

Overview of Climate Models.

3.2

PACIFIC NORTHWEST

CLIMATE TRENDS

In the PNW, average air temperatures increased about

1.3°F between 1895 and 2014.65 The greatest increases

were seen in the winter and at lower elevations.66

Natural variability plays a strong role in air temperature

and annual precipitation trends, but the extent of the

influence of natural variability in the long term is a subject

of debate among scientists.67 While precipitation

naturally varies between years and decades, heavy rainfall

events have increased in frequency and intensity beyond

the natural variability. For example, the extreme rainfall

events that fall in the top 1 percent of all daily events

increased in frequency by 12 percent in the PNW

during the 20th century.68

The local climate variations on the yearly and decadal

basis are due in large part to regional climate patterns

known as the Pacific Decadal Oscillation (PDO) and

the El Niño-Southern Oscillation (ENSO). The PDO is a

20- to 30-year cycle that tends to produce warmer and

drier winters in the warm phase and colder and wetter

winters in the cool phase in the PNW. In our region, El

Niño years tend to produce warmer and drier winters,

while the opposite phase, known as La Niña, produces

cooler and wetter winters. If ENSO and PDO fall into

phase, temperature and precipitation extremes are likely

to follow. These regional annual and decadal climate

cycles can temporarily mask climate change effects during

cooler phases, but the ensuing warming phases will

then intensify impacts. Because of these natural climate

variations, accurate tracking of the PNW climate change

signal requires a time frame covering many decades.

Changes to the PNW climate, along with the increase in CO2

in the atmosphere and oceans, lead to a host of impacts

across the region. These impacts are described in detail

in the subsequent chapters of the report. In summary, the

observed and projected climate trends in the PNW include

the following:

·· Warmer air temperatures;69

·· Shrinking glaciers;70

·· Less snowfall;71

·· Decreasing summer streamflows;72

·· Increasing winter peak flows;73

·· Changes to timing of peak and base flows;74

·· Higher stream and lake temperatures;75

·· Lower levels of dissolved oxygen in streams;76

·· More sediment delivered into, carried by, and

deposited in streams;77

·· Drying out of wetlands;78

·· Increased frequency and size of wildfires;79

·· Greater probability of landslides;80

·· Warmer ocean temperatures;81

·· Rising sea levels;82

·· Stronger storms and greater storm surge;83 and

·· Changing ocean chemistry, including ocean

acidification.84

3.3

REGIONAL CLIMATE

PROJECTIONS

Regional climate models suggest continued changes across

the PNW due to global warming. Future climate projections are

based on the GHG concentrations already in the atmosphere

along with a range of future GHG emission scenarios and the

natural variability of the global climate. For more details on how

projections are modeled, see Appendix D: An Overview of

Climate Models.

Air temperatures in the PNW are projected to rise 4.3 to

7.1°F by the middle of the 21st century as compared to what

they were at the end of the 20th century based on a high

or “business as usual” GHG emission scenario.85 By the last

decades of the 21st century, the average annual temperature

will rise even more, with the greatest increase seen in the

summer.86 Projections for the amount of average annual

precipitation vary, with some models projecting increases

and some projecting decreases. Nonetheless, summers are

generally projected to be as much as 30 percent drier by the

end of the century.87 Extreme rainfall events are projected

Climate Change and Our Natural Resources

to be more severe—the highest daily rainfall for a given year

is projected to increase by 4 to 30 percent by the mid-21st

century, depending on the model.88

3.4

OVERVIEW OF IMPLICATIONS FOR

TREATY-PROTECTED RESOURCES

Changes to climate conditions such as temperature

and precipitation drive changes to physical systems that

interact with one another in many cases. These changes

in environmental conditions drive biological responses

that also interact with one another. Organisms respond to

environmental change that threatens their survival by altering

their behavior, changing the timing of life phases, moving into

more favorable locations, or adapting though evolution.89

Each species and even local populations within a species may

respond differently to climate change depending on their

sensitivity to environmental change and their ability to adapt.

Threats to the persistence of any species are particular to each

individual population and will depend on the local conditions.

Species must be able to keep pace with the velocity of

climate change, which is how fast climate conditions

change.90 The rate that species must shift their range in

order to maintain suitable habitat depends on local climate

velocities.91 Where the rate of change is too rapid, it will

be difficult for plants, animals, and human communities to

adapt. How well a species is able to persist amid changes

to environmental conditions will also depend on its ability

to move through the landscape and to take advantage

of local variations in conditions.92 Biological dispersal, or

the movement of individuals, seeds, or spores, can affect

genetics, species distribution, and population dynamics.

Dispersal not only depends on the characteristics of the

species in question, but also on the presence of barriers,

both natural (e.g. waterfalls) or artificial (e.g. dams). Species

interactions such as competition and predator-prey

relationships also strongly influence the ways climate change

influences species distribution, population decline, and the

composition of assemblages.93

Although detailed projections of individual biological

responses to environmental change are beyond the scope

of this report, an overview of the some of the significant

threats to treaty-protected resources due to climate change

is as follows:

A Report from the Treaty Tribes in Western Washington

Declining runs of salmon and steelhead due to

changes in streamflow, stream temperature, levels of

dissolved oxygen, amount of sediment in streams,

susceptibility to disease, ocean temperatures, ocean

chemistry, timing of prey availability, prey type, and

competition from warm-water species.94

Migration of marine fish away from historical fishing

grounds as they seek out cooler ocean temperatures.95

Replacement of traditional fish runs with invasive

species and new species that have migrated from

the south.96

Declining populations of shellfish (both mollusks

and crustaceans) due to changing ocean chemistry.97

Closing of shellfish harvest areas due to harmful

algal blooms.98

Loss of traditional shellfish harvesting areas, forage

fish spawning grounds, and important cultural

sites to sea level rise or increased coastal erosion.99

Loss of water supplies for drinking and other needs

due to saltwater intrusion from sea level rise, or changes

to precipitation, streamflow, and/or groundwater

availability.100

Declining populations of wildlife and birds due

to habitat changes, loss of food sources, disease, and

competition with invasive species.101

Migration of wild game and birds out of traditional

hunting grounds as they move further north or to higher

elevations.102

Decreased plant productivity and shifts in species

ranges due to heat stress, drought, invasive species

encroachment, or increasing pests.103

Loss of traditional hunting grounds, plant

gathering areas, and sacred sites due to wildfire,

landslides, or invasive species.104

Loss of access routes to important cultural sites

due to flooding, bridge damage, permanent road

closures, or landslides.105

Changes in timing of key life stages in a variety

of species, such as the migration of salmon, fruiting of

berries, or optimal time to harvest cedar bark.106

Negative health outcomes from poor air quality, heat

stress, spread of diseases, loss of nutrition from traditional

foods, and loss of opportunities to engage in traditional

cultural activities.107

4. FRESHWATER AQUATIC

ENVIRONMENTS

4.1

·· Decreasing snowpack and the melting of mountain

glaciers;109

·· Decreasing summer streamflows, increasing winter

peak flows, and changes to the timing and profile of

annual hydrographs;110

·· Warming stream temperatures;111

·· Increased sediment loads in streams;112

·· Changes to wetland hydrology;113

·· Altered aquatic food webs;114 and

·· Conditions that favor non-native, invasive species.115

CHAPTER SUMMARY

Traditions of fishing are essential to our tribal culture.

Climate change threatens salmon, trout, and other

aquatic species by affecting their growth, reproduction,

susceptibility to disease, and timing of key life changes.

Individual species and even distinct runs of the same

salmonid species will respond uniquely depending

on their level of tolerance to changing conditions.

Nonetheless, a number of the factors that have historically

limited salmon and trout populations are worsened

by climate change, including changes in streamflow,

increased stream temperature, channel instability, excess

fine sediment loading, and lack of habitat complexity.108

These legacy impacts in combination with climate change

have repercussions for the natural systems that we rely

upon for subsistence, economy, culture, and spiritual

identity. The ability of freshwater systems to adapt to

climate change is improved where natural processes

can promote optimal ecosystem health and function.

The key impacts of climate change to freshwater systems

include the following:

4.2

PEOPLE OF THE SALMON

The importance of freshwater systems to our lives cannot be

overstated. Archaeological evidence suggests that salmon

were used consistently by indigenous peoples in the PNW

for the last 7,500 years despite the natural disturbances that

periodically put pressure on salmon populations.116 Today,

salmon and trout are valuable sources of nutrition, income,

and cultural continuity for our communities. Salmonids are

rich in essential fatty acids, protein, and nutrients associated

with reduced risk of heart disease, diabetes, and cancer.

Fishing also provides a source of spiritual fulfillment and an

opportunity to connect with family, friends, the land, and the

water.117 In traditional belief systems, water itself is sacred and

connects humans, animals, plants, and the land through the

continuous flow of the hydrological cycle.118

“It’s not just fish survival,

but our own.”

Terry Williams, Treaty Rights

Office Commissioner,

Tulalip Tribes and NWIFC

Commissioner

A Skokomish tribal fisherman hauls his net during a fishery in Hood Canal.

Photo: Tiffany Royal, NWIFC.

Climate Change and Our Natural Resources

Salmon and trout populations have declined from historical

levels throughout western Washington. Although direct

counts are not available, it is estimated that native salmonid

runs are less than 10 percent of the runs in the late 1800s.119

Under the Endangered Species Act (ESA), Puget Sound

spring chinook, Lake Ozette sockeye, and Hood Canal/Strait

of Juan de Fuca summer chum were listed as threatened in

1999. Steelhead were listed as threatened under the ESA in

2007, and bull trout were listed as threatened by the U.S. Fish

and Wildlife Service in 1999.

4.3

SNOWPACK AND GLACIERS

Snowpack and glaciers act as storage for water that is

released gradually with melting in the spring and summer.

The climate change impacts to snowpack and glaciers are

closely linked to stream temperatures, streamflows, and

sediment dynamics. These aspects of climate change impacts

to freshwater systems are discussed below in Section 4.4:

Stream Temperatures, Section 4.5: Streamflow Patterns, and

Section 4.6: Sediment in Streams.

As snowpack and glaciers decline due to climate change,

rivers will see lower flows and higher stream temperatures

in the summer, during critical salmonid life stages.120 With

the reduced area of snow accumulation, increased winter

precipitation in the form of rain on the exposed landscape

will lead to more runoff and increasing winter peak flows.121

Less summer precipitation and loss of snowpack may reduce

availability of water at the same time that human population

growth creates greater demand for water. This demand can

further reduce streamflows unless minimum instream flows

are protected. Lower summer flows will also have an impact

on hydropower generation, sediment transport, and nutrient

loading in streams.

Warmer temperatures melt more snow earlier in the

spring and cause more precipitation to fall as rain instead

of snow. An example of the effects of warming air

temperatures on snowpack can be seen in the extremely

low snowpack of the winter of late 2014 and early 2015.

Although total precipitation was at near normal levels,

record-breaking temperatures from October 2014 to

March 2015 were 4.7°F above the 20th century average.

More precipitation fell as rain rather than snow in the

zones where snow usually accumulates during winter.

By May 15, 2015, Governor Jay Inslee declared a

statewide drought emergency and the average snowpack

in western Washington was at 10 percent of the median

value for 1981 to 2010, with the lowest levels measured

in the Olympic and Central Puget Sound basins.125

Although the causes of this event are tied to regional

climate variability, the results offer an indication of future

snowpack conditions in a warmer PNW.

With few exceptions, glaciers are diminishing

throughout the mountain ranges of Washington.

Glaciers are decreasing in number, surface area, depth,

and surface mass balance (the difference between snow

accumulation and loss). In Olympic National Park, glacier

surface area decreased 34 percent from 1980 to 2009.126

The Anderson Glacier, one of the sources of the Quinault

River, lost more than 90 percent of its surface area

between 1927 and 2009 (Figure 3).127 The glacier has

essentially lost its ability to survive without its zone of

accumulation of snow and ice. The Blue Glacier, which

drains into the Hoh River, retreated about 325 feet (100 m)

between 1995 and 2006.128

Observed and Projected Changes

The area and depth of snow accumulation are declining

in western Washington. Warming trends are the main

driver, but regional climate variability also plays a role.122

Snowpack quantity is commonly represented by the snowwater equivalent (SWE), or the amount of water held in the

snowpack on April 1. In the western U.S., the SWE decreased

by approximately 20 percent between 1950 and 2000.123

The largest declines in snow accumulation were in areas

where winters are mild, such as the Cascade Mountains.124

A Report from the Treaty Tribes in Western Washington

Figure 3: Photographs of Anderson Glacier show its significant retreat in the 20th

century. The arrows mark the edges of the glacier in 1936 in both images. Source: ONP

2015 (1936: Asahel Curtis, 2004: Matt Hoffman, Portland State Univ.)129

In the North Cascades National Park Service Complex,

glaciers have shown substantial losses.130 The glaciers of

Mount Baker, which feed the Skagit and Nooksack rivers,

have receded by an average of 957 feet between 1993

and 2013.131 In the Skagit River basin, total loss of glacier

area since 1900 is estimated at around 50 percent.132

The Nooksack Indian Tribe monitored glacier ablation

of the Sholes Glacier on Mount Baker in the Nooksack

River basin in 2015. The tribe measured 12.5 feet of total

ice ablation from mid-July to mid-September, with a daily

ablation rate as high as 8.3 inches.133 The amount of

ablation was greater than the amount of accumulation by the

equivalent of 11 feet of SWE, the greatest of any season over

the last 31 years.134

Projected increases in air temperature will result in a shorter

snow season as more precipitation falls as rain and snow melts

earlier in the spring. Average spring snowpack in Washington

state is projected to decline by 65 percent by the 2080s for a

moderate GHG emissions scenario.135 In a study of four Puget

Sound watersheds (the Cedar, Green, Tolt, and Sultan), the

largest SWE reduction was projected for lower elevations. For

Climate Change and Our Natural Resources

example, the low-lying valleys of the Upper Green and

Cedar watersheds were projected to see 90 percent less

SWE starting in the 2020s. By the 2080s, the SWE is

projected to completely disappear at high elevations for

all four watersheds. Peak spring snowmelt is projected

to occur three weeks earlier by the 2040s and six weeks

earlier by the 2080s for these basins.136 Projections for the

Middle Fork Nooksack River basin show a 69 percent and 87

percent decrease of ice extent by the end of the century for

a moderate and high GHG emissions scenario, respectively.

In the North Fork Nooksack River basin, which has the largest

area of glacial ice within the Nooksack River basin (12 square

miles), ice extent is projected to decrease by approximately

66 percent and 88 percent for moderate and high scenarios,

respectively, by 2099.137

4.4

STREAM TEMPERATURES

As air temperature rise, so do stream temperatures. Warmer

stream temperatures threaten salmonids, which are coldwater species with narrow temperature requirements in all life

phases. If stream temperatures warm by even a few degrees

above their optimal range, salmonids can experience negative

effects unless they can adapt or find thermal refugia, the

cooler zones within the channel. The species that are most

vulnerable are those that spend the most time in fresh water

before out-migration, such as chinook, coho, steelhead, and

bull trout.138 As cold-blooded fish, salmonids experience

higher metabolic rates in warm water. They can grow more

quickly or they can experience reduced growth if there is not

enough food available.139 Faster growth rates can leave them

physiologically ready for out-migration before the streamflows

are high enough to carry them downstream.140 Temperatures

in the range of 70 to 75°F (21 to 24°C) interfere with the

physiological transition from fresh water to salt water and

result in greater vulnerability to predators.141

High water temperatures leave salmonids with greater

susceptibility to diseases and parasites. Columnaris and

freshwater ich, diseases lethal to salmonids, are more

prevalent in warmer water.142 Salmonids also have greater

susceptibility to the effects of toxic chemicals in the water

when temperatures are high.143 Warmer water can hold less

dissolved oxygen (DO), which is critical for the health of fish

and other aquatic organisms. Rising stream temperatures also

accelerate aquatic food web processes and decomposition,

which further lowers DO. The combination of these processes

can create hypoxic zones that are lethal to aquatic life. DO

A Report from the Treaty Tribes in Western Washington

levels can also affect growth, swimming behavior,

and susceptibility to disease and other environmental

stressors.144 DO in streambed gravel is critical for

salmonid egg and embryo development and survival.145

DO levels in the gravel may be lower than in the water

column, especially in locations with low stream slope,

fine channel bed sediment, or where there are multiple,

superimposed redds.146

Warmer summer stream temperatures may alter aquatic

food webs and can create favorable conditions for

non-native fish species that compete with salmonids for

habitat and prey.147 High stream temperatures can also

create barriers that salmonids will not cross. For example,

water temperatures in the White River, a tributary to the

Puyallup River, reached 72°F in early July 2015. Russ

Ladley, Resources Protection Manager for the Puyallup

Tribe of Indians, explained that, “if the water in the lower

river is too warm, it’s likely [that] fish will delay entry or

go somewhere else. Even if some fish do try to head

upstream, they might die before they spawn because of

the warm water.”148 Thermal barriers can limit connectivity

of habitat and reduce fish population resilience to

environmental change.

Observed and Projected Changes

Stream temperatures in many western Washington

locations regularly exceed the optimal temperatures

for fish in all life phases, particularly during summer.

Temperatures in PNW streams warmed by about

0.4°F (0.22°C) per decade from 1980 to 2009.149

Air temperature was the dominant driving force in the

long-term stream temperature trends, but low streamflow

accounted for 52 percent of the change during the

summer.150 Human modifications to watersheds also play a

role. Removal of streamside forests, channel straightening,

runoff from impervious surfaces in the watershed, and

subsequent changes to channel geometry all contribute

to elevated temperatures. Studies in the South Fork

Nooksack River suggest that legacy impacts could have

caused an increase in stream temperature of 2.9°F (1.6°C)

in addition to the impacts of climate change.151

Projected conditions of increased air temperatures, lower

streamflow, and loss of ice and snow all point to warmer

stream temperatures. Below is a summary of projections

for stream temperatures in the PNW:

·· Compared to the average stream temperature

from 1993 to 2011, mean August stream

temperatures in western Washington are projected

to increase 2.5°F (1.4°C) on average by the 2040s

and 4.25°F (2.4°C) by 2080 for a moderate GHG

emissions scenario.152

·· Warmer air temperatures will result in 16 percent

more stream locations with weekly summer stream

temperatures in excess of 67°F, which is stressful to

salmonids, by the 2080s under a moderate GHG

scenario (Figure 4).153 For example, summer stream

temperatures in the South Fork Nooksack are

projected to increase 12.6°F (7°C) by the 2080s

for a moderate GHG emissions scenario. River

temperatures may reach 77.2°F (25.1°C), which is

above the lethal limit for adult spring chinook.154

·· The length of time that rivers exceed salmonid

thermal thresholds will be longer. By the 2080s,

many stream locations will exceed salmonid

temperature tolerances for the entire summer—

even locations that did not exceed these

temperatures in the past.155

·· Temperature increases are greatest at low

elevations, where rivers are slower and wider,

and where air temperatures are warmer.

4.5

STREAMFLOW PATTERNS

Salmonids and other aquatic organisms are adapted to

seasonal cycles of streamflow to which they synchronize

their life phases. Disruption of the timing and quantity of

water in streams can have repercussions for these species

and for the tribes that rely upon them.156 Large annual peak

flows are correlated with low chinook salmon productivity.157

The Stillaguamish Tribe has found a correlation between

increasing annual peak flows and low juvenile chinook survival

rates (Figure 5).158 This is likely due to harmful effects to egg

incubation and survival. Greater frequency and magnitude of

flood flows also increase the amount of sediment transported

by the stream, subjecting salmonid redds to suffocation

and entombment by fine sediment (discussed in Section 4.6:

Sediment in Streams).159 Heavier storm events can also increase

the discharge of pollution from runoff into streams, including

pesticides, herbicides, and excess nutrients.160

Increasing peak flows can also wash out salmonid redds.

For example, chum bury their eggs just below the typical

depths of streambed scour. A small increase in scour depth

due to higher flows can wash out eggs before the fry

emerge.161 Higher winter flows can also wash juvenile salmon

downstream before they are ready, forcing them to compete

for limited habitat.162

Figure 4: Average summer temperatures and salmon thresholds as observed in the 1980s (left) and projected for the 2040s under a

moderate GHG emission scenario (right). The dots represent water temperature monitoring sites and the continuous color represents air

temperatures. Source: Mantua et al. 2010.

Climate Change and Our Natural Resources

Figure 5: Egg-to-migrant survival for juvenile chinook in the Stillaguamish River under a range of annual peak flow

magnitudes. Source: Stillaguamish Tribe of Indians.

Lower summer streamflow reduces water availability for

aquatic habitat, fish hatcheries, irrigation, and drinking water.

Available habitat is reduced and fish passage is limited.163

Low flows during spawning season also force fish to build

their spawning redds in the main channel of the river where

they are more vulnerable to scour during winter peak flows.164

Extremely low flows in the Dungeness River in August

2015 posed a challenge for salmon migrating upstream,

especially chinook, whose large body size requires deeper

water. The Jamestown S’Klallam Tribe partnered with the

Washington State Department of Fish and Wildlife (WDFW)

and Washington Conservation Corps to construct temporary

channels and pools in the river bed to enable fish passage.

Simultaneously, low flows in the Sol Duc River of the Quillayute

River system required that WDFW and the Quileute Tribe take

action to help fish access their spawning grounds.

Lower water levels can disconnect streams from their

floodplains, restricting fish access to off-channel habitat. Less

water availability can also cause tributaries that are important

for salmonid rearing to lose all surface flow and go dry. When

all flow goes below the surface, the stream loses connectivity

to the rest of the river system and fish can become stranded.

Lower flows can reduce survival of juvenile salmon.165

Slower flows increase the time of out-migration, exposing

A Report from the Treaty Tribes in Western Washington

the juveniles to predation. Low flows also concentrate

pollutants and exacerbate water quality impairments in

streams.166 Less water increases water temperatures, which

reduces dissolved oxygen and promotes the spread of

disease in aquatic organisms (discussed in Section 4.4:

Stream Temperatures).167

Lower streamflows also have the potential to impact

salmon and steelhead hatcheries. These hatcheries play a

role in the exercise of tribal treaty rights by mitigating the

loss of natural fish production due to habitat degradation

and other human-caused disturbances. In Puget Sound,

hatcheries contribute 70 to 80 percent of the coastal

salmon and steelhead catch.168 Changes to freshwater

systems can affect hatchery operations in multiple ways,

from reducing the quality and amount of available water

to worsening the conditions of the waters into which the

fish are released.169

Observed and Projected Changes

Changes in precipitation patterns, increasing air

temperatures, decreasing snowpack, and loss of

mountain glaciers are altering hydrological processes in

many watersheds. Streamflow trends vary considerably in

the PNW, depending on location and the characteristics

of the watershed. Rivers in western Washington generally

fall into three hydrological categories based on their

response to the precipitation type in winter (Figure 6):

Rain-dominated rivers run primarily through elevations

below the snowline where most precipitation falls as rain.

These rivers usually have a single peak in flow during the

wet winter months since they respond directly to rainfall.

Transient snow, also called mixed rain-snow, systems

flow through moderate elevations where precipitation

alternates as snow and rain over the course of the winter.

Rivers in these areas generally show two peak flows—one

in early winter during storm events and one in spring and

early summer during snowmelt.

Snow-dominated rivers have sources at high elevations

where precipitation falls mainly as snow in the winter and

is stored as snowpack or on glaciers. These rivers exhibit

a large peak flow in spring and early summer as the snow

and ice melt.

Observed changes since the middle of the 20th century

include the following:

·· Summer streamflows in snow-dominated and transient

snow watersheds are declining, especially in areas

such as western Washington where temperatures

during the snow season do not fall far below

freezing.170

·· From 1950 to 2010, summer streamflows decreased

33 percent in snow-dominated watersheds and 36

percent in transient snow watersheds.171 For example,

summer flows decreased 28 percent in the Nooksack

River and 21 percent in the North Fork Nooksack from

1963 to 2003.172

·· Across western North America, the date of annual peak

flows in rivers shifted 10 to 30 days earlier in the spring

between 1948 and 2002. The signal was largest in

PNW watersheds influenced by snowmelt.173

Figure 6: Typical hydrological regimes of PNW rivers showing representative peak and base flow timing in rain-dominated, transient

snow (or rain- and snow-dominated), and snow-dominated watersheds. Source: after Elsner et al. 2010.

Climate Change and Our Natural Resources

Projections of regional climate change impacts in western

Washington indicate a shift in the timing of hydrological

patterns. The projected changes are as follows:

·· By the 2080s the timing of streamflow will shift in

snow-dominant and transient-snow watersheds. For

example, peak streamflow will occur 4 to 9 weeks

earlier by the 2080s for four Puget Sound watersheds

(Green, Cedar, Tolt, and Sultan).174 Timing of peaks

will remain largely unchanged in rain-dominated

watersheds.

·· The double peak hydrograph of transient watersheds

will shift toward a single-peak, rain-dominant profile

as more precipitation falls as rain rather than snow

and with earlier melt of the snow that does fall. For

example, the Quinault River is projected to shift to a

single-peak hydrograph by the 2040s (Figure 7).175

·· Winter flood risk will increase due to heavy

precipitation events increasing in both frequency and

intensity. Annual runoff in Washington will increase

2 to 3 percent by the 2040s driven mainly by

more winter precipitation.176 Rising snowlines

also increase winter flood risk by exposing more

watershed area that can contribute to runoff.

·· Summer base flows will decrease, particularly for

rain-dominated and transient-snow watersheds

west of the Cascades.177 Low flow conditions

will become more severe for about 80 percent

of watersheds in Washington.178 For example,

considerable low flow impacts are projected

across most of the Olympic Peninsula, regardless

of watershed type.179

·· Future projections indicate that glacier melt

contribution to summer base flows will continue to

increase, until the glaciers disappear entirely.180

·· Warmer air temperatures will increase evaporation

and evapotranspiration by vegetation, the process

by which plants draw water out of the soil and

release it into the atmosphere. This will also

worsen summer low flows.181

Figure 7: Streamflow changes in

the Quinault River during the 20th

century. Projections for the 2040s

show a shift from two periods of

high flows to one. The 2040s curve

is shaded to represent a range

across a number of different climate

scenarios. Source: University of

Washington Climate Impacts Group

cited in USGCRP 2009.182

A Report from the Treaty Tribes in Western Washington

Taking Action: Jamestown S’Klallam Tribe’s Strategy for

Dungeness River Floodplain Protection and Restoration

The Dungeness River in the northern

Olympic Peninsula is the ancestral

river of the Jamestown S’Klallam Tribe.

Four salmon and char species in

the Dungeness River watershed are

currently listed as threatened under

the ESA: Puget Sound chinook, Hood

Canal/Strait of Juan de Fuca summer

chum, Puget Sound steelhead, and bull

trout. In the Jamestown S’Klallam Tribe’s

2013 Climate Change Vulnerability

Assessment and Adaptation Plan,

salmon were ranked as a Very High

Priority.183 Recovery of Dungeness

River salmon and char will require the

restoration of a significant amount of

floodplain that has been disconnected

from the main channel by dikes, roads,

and other infrastructure.184 Reconnecting

the floodplain to the river will also

help ameliorate the impacts of climate

change. Negative impacts to salmon

are expected as river temperatures

rise and flows increase during rearing

and egg incubation life phases. Along

with the shade provided by floodplain

forests, hydrological connectivity

with floodplains allows high flows to

spread and dissipate energy. Restoring

side-channel connectivity will provide

off-channel refugia for juvenile salmon

during winter months and may provide

access to spawning areas outside the

deepest parts of the main channel

during summer low flows, so salmon

redds are not located where they will

Figure 8: The contemporary floodplain of the lower 2.8 miles of the Dungeness River

covers 169 acres (shown in blue), whereas the pre-1963 floodplain extended over 730

acres (shown in black). Source: Jamestown S'Klallam Tribe.

be most vulnerable to scour during

high flows. Events such as a series of

damaging floods between December

2014 and February 2015 and the recordbreaking low flows of the summer of

2015 are increasing the importance and

urgency of implementing a floodplain

restoration and protection strategy.

The tribe has identified a number of

projects to reconnect 340 acres of

the 561 acres of floodplain that have

been disconnected from the river by

infrastructure since 1963 (Figure 8). The

projects focus on the removal, setback,

or reconfiguration of dikes, roads, and

undersized bridges in the floodplain.

Over the last two decades the tribe

has purchased 140 acres of floodplain

properties in the Dungeness River

corridor to protect high-quality habitat

or to restore degraded habitat for the

benefit of ESA-listed and culturally

significant salmon. The tribe also intends

to establish native riparian forests and

restore large logjams in the river. In

2015, the tribe replaced a historic

railroad bridge and approach trestle,

which had degraded Dungeness River

geomorphic function by constricting the

natural processes of channel migration.

The trestle bridge, which has important

historical, cultural, and recreational value

for the tribe, was also vulnerable to

flooding. After the trestle was damaged

by a flood in February 2015, it was

replaced with a new 750-foot structure

that spans the entire floodplain and

channel migration zone. The trestle

replacement restored salmon habitatforming processes to approximately

20 acres of floodplain, numerous

side channels, and 2,000 feet of the

Dungeness River main channel.

Climate Change and Our Natural Resources

4.6

SEDIMENT IN STREAMS

The rivers of western Washington transport sediment from a

variety of sources, such as weathering of bedrock, erosion of

soils, landslides, channel bank erosion, mudflows originating

on volcanoes, and erosion of glacially derived sediment.

Accurate and up-to-date data for the amount of sediment

transported by rivers in western Washington are incomplete

for many watersheds.185 Several member tribes have initiated

studies aimed at assessing current sediment dynamics as

well as projecting sediment dynamics with continued climate

change. For more discussion of issues related to landslides

and other forms of mass movement, please see Section 6.8:

Landslides and Mass Movement.

Sediment delivery into and transport through streams are

natural processes that build vital habitat in aquatic and coastal

systems. However, when land use, river modifications, or

changing hydrological regimes lead to excessive sediment

delivery, the results can be harmful to fish and other aquatic

organisms. Many rivers in western Washington are degraded

by excessive amounts of sediment, particularly fine-grained

sediment suspended in the water. Excessive fine sediment

loads in rivers can be caused by mass wasting and surface

erosion from managed forestlands entering streams. It can

also be caused by increased levels of bank erosion after

removal of the riparian vegetation that enhances bank stability

and traps fine sediment from upland runoff. High sediment

loads can also occur due to the disconnection of the channel

from adjacent floodplains and wetlands, where fine sediments

settle out during overbank flows. In agricultural and urban

areas, increases in fine sediment delivery can also occur

through dredging, bank erosion from livestock access, and

surface erosion of cropland, construction sites, and unlined

ditches. These legacy impacts have altered the natural habitatforming geomorphic processes and sediment dynamics in

many western Washington rivers.

Increased fine sediment in rivers can harm salmonids in

multiple ways. It reduces survival from the egg-to-fry phase

and increases juvenile salmonid mortality.186 Excess fine

sediment can cause gill trauma and disrupt internal fluid

regulation, blood chemistry, and reproduction. It reduces

insects and other invertebrates living in the substrate that are

critical for the aquatic food web.187 High turbidity can reduce

the feeding efficiency for juvenile salmonids, which are visual

predators, thereby reducing growth rates.188 It can also cause

the fish to avoid habitats or delay their migration.189

A Report from the Treaty Tribes in Western Washington

Where sediment supply exceeds sediment transport

capacity, sediment collects on the channel bed through

a process called aggradation. Aggradation of coarsegrained sediment like gravel and cobbles changes the

configuration of the channel by raising the elevation of

the channel bed. This exacerbates stranding and other

barriers to fish movement during low flows. This sediment

can also directly bury salmonid redds and can increase the

risk of flooding, especially where floodplains have been

disconnected from the channel.

Observed and Projected Changes

The USGS has estimated that about 6.5 million tons of

sediment are transported by rivers into Puget Sound

and adjacent waters.190 Estimates for each major river

system range from 330,000 tons for the Lake Washington

Ship Canal to 2,800,000 tons for the Skagit River. While

changes brought about by global warming may worsen

the impacts of sediment impairment in streams, land use

and changes to land cover continue to play a major role.

Globally, soil erosion is projected to increase about 14

percent by the 2090s relative to the 1980s. Of this amount,

9 percent is due to climate change and 5 percent to

land-use changes.191 For example, on a heavily regulated

river such as the Columbia River, the impacts of human

modification to flow far outweigh the effects of climate

change when it comes to sediment transport rates.

Projections of climate change impacts to sediment

in streams are not well documented. Nonetheless,

potential effects can be inferred from the impacts to

the temperature and hydrological regimes that drive

geomorphic processes in the PNW. For example,

the effects of climate on sediment transport rates are

expected to be greater than on streamflow because the

relationship between increasing flow and increasing

sediment discharge is not linear.192 Sediment loads

have increased in the Skagit River basin due to glacier

retreat, especially in the Sauk and Cascade rivers, and are

expected to continue to rise due to glacier loss, reduced

snowpack, and larger peak flows, especially in rivers

without dams that trap sediment such as the Sauk.193 In the

Skagit River, average annual sediment loads are projected

to increase by 149 percent and peak winter sediment

loads by 335 percent by the 2080s.194 At the local

watershed scale, land use and management practices will

also determine changes in sediment loads.

Most streams and rivers in western Washington flow

through glacial sediments that are easily eroded and

transported. As glaciers recede, they expose vast

quantities of sediment that are then readily washed down

into rivers. For example, a USGS study of the rivers arising

from the glaciated slopes of Mount Rainier found that

pronounced aggradation between 1984 and 2009 in

the Puyallup, White, and Carbon rivers had increased

the average channel bed elevations by 7.5, 6.5, and 2

feet, respectively.195 Melting glaciers leave behind oversteepened valley slopes that are susceptible to mass

failure as the protective snow cover disappears. These

rock avalanches and debris flows temporarily increase

sediment loads.196 For example, Mount Rainier received

18 inches of rain in 36 hours in November 2006, resulting

in glacial outburst floods that triggered debris flows.

The accumulation of the transported material increased

the elevation of the channel bed by 4 feet.197 Sediment

sources from the surface and inside glaciers can also

provide substantial sediment loading as glaciers melt.

The Nooksack Indian Tribe has documented conditions

in glacier-fed streams of Mount Baker using turbidity as a

surrogate for suspended sediment in the water column.

They found that the turbidity spikes during glacier melt

periods on the Sholes Glacier, which has receded over

190 feet in the last five years.198

Warmer air temperatures increase the amount of sediment

available for delivery into streams by speeding the

breakdown of soils and reducing the amount of snow

cover protecting the ground from runoff. Heavier and

more frequent rain events enhance soil erosion and

sediment loading.199 These rain events will increase

river flows and hence, sediment inputs into lakes and

streams.200 More precipitation falling as rain instead of

snow can also increase the risk of landslides. Saturated

soils are more likely to fail, potentially delivering more

sediment into streams. Increased sedimentation in

streams can also result from erosion during rainfall

after wildfires.

4.7

FRESHWATER WETLANDS

Wetlands serve many critical functions in freshwater

systems. They provide habitat for a variety of animal

and plant species, absorb floodwaters, stabilize stream

banks, and filter sediment, nutrients, and pollutants

Chinook salmon returning to the North Fork Stillaguamish River in

2015 faced record high temperatures and low flows. Photo: Kari

Neumeyer, NWIFC.

before water enters a stream. Wetland plants are a food

source for the aquatic insects and fish that are prey for larger

fish, mammals, birds, amphibians, and reptiles. Seasonal

floodplain wetlands provide rearing habitat for a variety of

fish, including salmonids.201 Juvenile salmon and steelhead

use floodplain wetlands as a refuge from high flows during

winter. One study of the floodplain wetlands of the Chehalis

River found high fish utilization, including coho, chinook,

chum, and cutthroat trout.202 Juvenile sturgeon and Pacific

lamprey may use wetlands as rearing habitat for several

years before migrating to the ocean. Adult sturgeon feed in

freshwater and brackish wetlands. Seasonal wetlands can also

provide critical habitat for non-game species such as threespine stickleback, sculpins, and the Olympic mudminnow.

The Olympic mudminnow is only found in limited areas of

Washington and is listed as a sensitive species by the state. It

is completely dependent on healthy wetland habitat for all life

phases, including spawning.203 Amphibians also use seasonal

wetlands in high numbers.204

Warmer temperatures due to climate change can hasten

drying of wetlands through direct evaporation of surface

water or through increased evapotranspiration of wetland

plants. Changes to streamflows alter the hydrological

characteristics of floodplain wetlands, affecting nutrient

availability, productivity, and species composition.

Conversely, loss of wetlands leads to loss of surface water

storage and groundwater recharge areas. As wetlands

diminish, so do habitats for wetland-dependent species and

Climate Change and Our Natural Resources

fish that use wetlands for spawning and rearing. Warmer

temperatures can also increase disease, including the fungal

and bacterial infections that can decimate fish, amphibian,

and reptile populations in wetlands.205

Observed and Projected Changes

The vulnerability of a wetland to climate change depends

on the interactions of precipitation, streamflow, snowmelt,

and groundwater. The hydrological characteristics

determine the depth and extent of a wetland, along with

the hydroperiod, or the duration, frequency, and seasonality

of inundation. Loss of snowpack and projected changes

in precipitation patterns that lead to drier summers will cause

wetlands to decline.206 Ephemeral wetlands, those that dry

out periodically, are especially vulnerable if the dry periods

last longer and occur more frequently in the future.

Wetlands at high elevations are particularly at risk because

they are dependent on snowmelt. Declining snowpack

and earlier snowmelt will reduce the extent of these

mountain wetlands.207

Wetlands that depend primarily on precipitation for their

water supply are highly vulnerable to the impacts of climate

change, while those that are dependent primarily on

groundwater flow can be less vulnerable.208 Groundwater

flows can potentially buffer these systems to changes to

surface water regimes, unless the watershed is too small

to support sufficient groundwater discharge.209 Increased

human demand for water can further decrease the amount

of surface and ground water available to maintain wetland

systems. Climate change impacts to freshwater wetland

hydrology occur in tandem with existing effects from human

activities. Wetlands that are already diminished or degraded

by pollution, water use, and habitat fragmentation will be

especially vulnerable.

Freshwater wetlands located on the coast can be vulnerable

to conversion to saltwater marshes due to sea level rise. One

study of multiple sites in Puget Sound and the Pacific coast

of Washington and Oregon estimated a loss of 13 percent of

inland freshwater marshes and 25 percent of tidal freshwater

marshes for all sites by 2100 under a moderate GHG emission

scenario.210 For more information on coastal impacts from sea

level rise, see Section 5.4: Sea Level Rise.

A Report from the Treaty Tribes in Western Washington

4.8

RESILIENCE IN FRESHWATER

ENVIRONMENTS

Resilience is the capacity of an individual or a

system to recover from significant disturbances

without major changes to its state or functions. In

relation to climate change it can be described as

the capacity to maintain biological diversity and

ecological function as the environment changes.211

Natural flow, sediment, and temperature regimes in

wetlands, floodplains, and riparian areas improve

resilience to climate change impacts such as low flows,

floods, and stream temperature for salmonid populations

and river ecosystems.

Fully functioning floodplains and riparian zones provide

resilience to a number of the impacts of climate change.

Floodplain forests and wetland complexes promote

groundwater recharge, store water during high flows, and

slowly release water during low flows. Floodplains also

allow fine sediment to settle out of flood flows before the

water returns to the main river channel. Floodplain forests

help stabilize off-channel habitat, which functions as a

refuge for salmonids during periods of high temperatures

or high flows.212

Riparian forests improve water quality through filtration

of nutrients, sediment, and chemical pollutants. Riparian

forests provide sources for large woody debris. Large

wood that falls into the river provides instream shade,

increases groundwater exchange, and promotes channel

forms like pools that can provide fish with refuge from

warm temperatures.213 Streambank vegetation adds to

bank stability, preventing excessive erosion and sediment

impairments in hydrologically modified stream systems.

Terrestrial vegetation is an important source of insects

and organic material that supports aquatic food webs

and provides food for salmonids. In addition, wildlife,

amphibians, and birds use riparian zones as habitat and

migration corridors. The loss of connectivity and diversity

of habitat in riparian zones limits the time and space that

organisms and assemblages have to adjust to changing

environmental conditions.214

A dynamic mosaic of freshwater habitats helps salmonids

cope with environmental disturbance.215 Habitat

complexity helps salmonids adapt to a warmer climate.216

For example, in the mountains of the northwestern U.S.

(including the Rocky Mountains), the rate that stream

warming is occurring is relatively lower in steep headwaters

even though air temperatures are generally warming faster at

high elevations.217 Cold-water species are finding refuge in

parts of the stream network that are cold and have low velocity

of change.218

An important feature in the resilience of salmonids is their

phenotypic plasticity—that is, they are able to shift their

physiological characteristics in response to environmental

factors without genetic changes.219 There are many instances

of salmon altering the timing of their life history phases

in order to adapt to unfavorable conditions in stream

temperature or flow.220 Nonetheless, salmonid responses to

climate change will be mixed depending on the stock and

location. For example, in a laboratory experiment two stocks

of steelhead from Hood Canal rivers only 50 miles apart

responded differently to changes in water temperature.221

Overall, populations occupying the warmest and most

degraded habitats will be at greater risk for extirpation

(local extinction).222

In some cases, evolutionary rescue, or relatively rapid

genetic change, allows population recovery in the face

of environmental disturbance that could have caused

extinction.223 One study of Columbia River sockeye found that

two-thirds of the observed shift toward earlier adult migration

is due to genetic evolution and the process of natural selection

acting against late migrants when stream temperatures become

too warm for their survival.224 The remainder of the shift is

attributed to phenotypic plasticity in response to river flows.225

The average migration of pinks into Auke Creek in Alaska is

occurring nearly two weeks earlier than it did 40 years ago,

and evidence suggests a genetic basis for the decrease in the

late-migrating individuals.226 While some species may be able

to adapt to changing conditions, our understanding of this

process is limited by uncertainty around species interactions

and climate change velocity.227

An adult coho. Photo: Debbie Preston, NWIFC.

Climate Change and Our Natural Resources

Taking Action: Nooksack Indian Tribe Climate Change Research

The salmon and trout stocks of the

Nooksack River watershed provide

sustenance and commerce for the

Nooksack Indian Tribe, along with vital

elements of traditional cultural and

spiritual identity and practices. Habitat

degradation is the leading cause of

the decline of the two Nooksack River

populations of spring chinook, which

are at 0.8 percent and 1.8 percent of

estimated historical levels. In addition,

climate change has caused and will

continue to cause impacts including an

increase in winter peak flows, reduced

area and depth of snow accumulation,

earlier snowmelt, decrease in summer

low flows, and an increase in water

temperatures that exceed salmon

tolerance or survival.

The Nooksack Indian Tribe has initiated

a comprehensive study throughout the

Nooksack River watershed to establish

baseline conditions, characterize

legacy impacts, model future impacts

of climate change on fish habitat and

survival, and develop restoration

strategies that promote resiliency

in the aquatic ecosystem. The tribe

has contracted with the University of

Washington and Western Washington

University to model historic and future

glacier behavior, stream temperature,

streamflow, and sediment dynamics

under various climate change scenarios.

Glacier Ablation: The tribe is

currently measuring glacier ablation in

terms of reduced area, melt rate, and

amount of melt water discharge.

Stream Temperature: The tribe

measures stream temperature at

66 seasonal and year-round stations

throughout the Nooksack River

watershed. Water temperatures

in the South Fork Nooksack River

frequently exceed optimal temperature

ranges and approach lethal limits for

salmonids. In partnership with the U.S.

Environmental Protection Agency’s

Office of Research and Development,

the tribe has initiated a pilot project

using the temperature total maximum

daily load (TMDL) designation.

The objective of the assessment was

to characterize climate change impacts

to salmonids and to identify and

prioritize restoration strategies to

ameliorate those impacts.

Stream Hydrology: The tribe

measures stream discharge at six

sites within the watershed. Some

of these sites are part of the NWIFC

Tribal Water Technical Group base flow

measurement project. This information,

along with three USGS gauge stations

in the basin, establish a baseline as

reference for future streamflow changes

due to climate change.

Sediment and Turbidity: The tribe

measures turbidity and suspended

sediment at 16 sites throughout the

upper Nooksack River watershed.

In addition, they collect bedload

and suspended sediment samples at

three bridges and with an automatic

suspended sediment sampler.

This network of sampling stations

allows them to determine baseline

sediment dynamics under current

conditions and to identify the major

sources of sediment in the watershed.

Adaptation: The tribe has analyzed

each reach of the South Fork Nooksack

River and prioritized adaptation actions

based on the highest level of positive

impacts expected.228 Floodplain

reconnection was identified as a

A Report from the Treaty Tribes in Western Washington

Nooksack Tribe water resources manager

Oliver Grah hikes up Sholes Glacier to

measure how much it is melting.

Photo: Kari Neumeyer, NWIFC.

high-priority action, including removal

or setback of hydromodifications

such as levees. Installation of logjams

was also identified as a means to

reconnect rivers to their floodplains.

Other priorities included riparian

revegetation, removal of invasive

vegetation, and rehabilitation of

channel modifications through

installation of engineered logjams

and narrowing of over-widened

channels. Restoration of streamflow

regimes though the reduction of water

withdrawals and the restoration of

floodplain wetlands was identified

as a priority as well. The assessment

also addresses increased sediment

delivery into streams, especially due to

landslides or forest roads. Actions focus

on monitoring sediment dynamics

over the long term, evaluating impacts

to fish habitat, and working with local

landowners and federal agencies to

limit sediment inputs to streams from

forested lands.

5. COASTALAND MARINE

ENVIRONMENTS

5.1

CHAPTER SUMMARY

Marine ecosystems provide us with food, employment,

and a host of cultural, social, and health benefits. Shellfish

(both mollusks and crustaceans) and other marine fish play

an important role in ocean ecosystems and the lifeways

of the tribes. Salmonids can spend years of their lives at

sea, depending on the species, so their survival is also

closely dependent on marine conditions. Climbing GHG

emissions are changing several key chemical and physical

properties of the ocean systems, and marine and coastal

ecosystems face challenges from the effects of

the following:

·· Warmer ocean temperatures;229

·· Rising sea levels;230

·· Flooding and coastal erosion due to greater storm

surge effects from sea level rise; and231

·· Changing ocean chemistry due to ocean

acidification and hypoxia, or low dissolved

oxygen.232

5.2

WHEN THE TIDE IS OUT,

THE TABLE IS SET

We have a traditional saying that conveys the significance

of coastal species to our people: “When the tide is out,

the table is set.” We harvest coastal species for food and

to use in tools and ornaments. Marine shorelines also

contain many archeological sites that hold great cultural

and spiritual importance to our peoples.233 Some tribes

historically expanded and actively managed shellfish beds

known as “clam gardens.”234 Today, shellfish harvests

continue to be important culturally, nutritionally, and

economically.235 Shellfish harvest provides physical activity

in a culturally and spiritually nourishing way. Shellfish

also have high levels of protein, essential fatty acids, and

nutrients needed to maintain health.

While marine fish, mollusks, and crustaceans are

important traditional foods, other types of shore species

such as dune grasses, seaweed, and kelp also are used

for food and crafts. Marine mammals such as otters, seals,

and whales have great cultural importance. Whales and

A Skokomish elder observes a chinook and pink fishery in Hood

Canal. Photo: Tiffany Royal, NWIFC.

whaling are central to the culture of the Makah Tribe. For

the Treaty of Olympia tribes (Quileute Tribe, Quinault Indian

Nation, and Hoh Tribe), gray whales, orcas, Pacific harbor

seals, and northern fur seals are among the most culturally

important marine mammals.236

5.3

OCEAN TEMPERATURES

The effects of warming ocean temperatures ripple through

the entire marine food web. Warm temperatures bring warm

water species to our region and challenge species that need

cold water to survive. Lower ocean productivity is linked to

warmer water. Warming can increase phytoplankton biomass

if enough nutrients are available, but this effect could be

reversed by a loss of nutrient supply due to seasonal vertical

stratification in the upper ocean.237 Nutrient supply into the

upper ocean is projected to decrease by over 40 percent

by 2100 relative to 1800 under a high GHG emissions

scenario.238 For example, warm ocean conditions off the

PNW coast in 2005 reduced surface phytoplankton biomass

by about 50 percent and primary productivity by about

40 percent.239

Ocean temperatures influence salmon migration

routes. The Fraser River sockeye and pink salmon that

return from the ocean to their natal streams in Canada

usually take one of two routes: either they go north

around Vancouver Island through Johnstone Strait,

Climate Change and Our Natural Resources

or they go south through the Strait of Juan de Fuca.

When these fish divert their migration to the north

and out of U.S. waters, the tribes that fish this run in

the Strait of Juan de Fuca lose their access. From 1990

to 2014 the average rate of diversion for Fraser River

sockeye to the north was 62 percent, and for pink the

average northern diversion rate since 1997 has been

56 percent. In 2015, the estimated diversion rates into

Johnstone Strait for sockeye and pink salmon were 99

percent and 91 percent, respectively.240 In the past,

northern diversion has been very strongly correlated

with warmer water off of Vancouver Island. Between

1906 and 1983, large northern diversions of Fraser

sockeye have occurred after El Niño years.241 Unusually

warm ocean conditions in 2015 may have spurred

the Fraser runs toward the north and away from our

fishing grounds.

Warm ocean waters can also affect salmon population

size, their age of return, and timing of return. When ocean

temperatures are warm, chinook are smaller in length,

weigh less for their size, and have lower return rates than in

cold ocean conditions.242 In our region, cold waters tend

to bring nutrients that feed plankton, which are eaten by

forage fish, which are in turn eaten by salmonids, birds, and

marine mammals. For example, cold-water conditions favor

certain species of copepods, a type of plankton. The coldwater copepods are rich in lipids (such as fatty acids) that are

beneficial to marine fish growth and survival. Warm-water

copepod species are smaller and have fewer lipids, so when

warm-water conditions dominate, the marine fish that salmon

eat carry less fat and the salmon have a lower probability of

marine survival.243

Temperature-related patterns have also been observed

with chinook and coho salmon returning to Oregon rivers.

High returns of chinook and coho corresponded with the

cool phase of the Pacific Decadal Oscillation (PDO) from

1947 to 1976. When PDO switched to a warm phase from

1977 to 1998, salmon returns below the average were more

common.244 Chinook salmon that entered the ocean along

the Oregon and Washington coast during warm conditions

due to the PDO were smaller and weighed less for their

size.245 The coho runs of 2015 in western Washington were

less than half of what was expected in most areas and most

of the fish that did return were 20 to 30 percent smaller than

normal.246 This has been attributed to poor ocean conditions

A Report from the Treaty Tribes in Western Washington

such as warm waters in the Pacific, compounded by the

ongoing loss of high-quality habitat in the freshwater

environment. The consequences will be low production

in these coho populations for years to come.

The marine food web could experience negative effects if

changes in the distribution and timing of plankton growth

causes a lack of synchrony, or a mismatch in timing, with

the many species that graze upon them.247 This could

change the distribution of marine species, including but

not limited to Pacific salmonids.248 An illustrative example

occurred along the West Coast in 2005, when a delayed

onset of the upwelling season caused major plankton

productivity to occur three to four months later than usual.

This produced a cascade of negative consequences on

plankton-dependent fish, seabirds, and marine mammals.

That year saw recruitment failure of many species of

rockfish, low chinook and coho survival rates, nesting

failure for Cassin’s auklet, and mortality of common

murres, sooty shearwaters, and other seabirds.249

Warmer waters cause marine species to shift their ranges

toward the poles in search of colder water. The average

rates of northward migration in 28 marine fish in the

northeast Pacific Ocean are projected to be about 18

miles (30 km) per decade under a high GHG emissions

scenario.250 At the same time, warm-water species will

become more common, bringing substantial changes to

ecological and economic systems by 2050.251 Population

shifts can lead to mismatches between species that have

evolved together and that depend on each other. It can

also lead to fishing grounds shifting away from historical

or established locations. Some species may become

extirpated, or locally extinct, in areas where the tribes

have traditionally fished for them, but we will not be able

to follow the fish. These projected patterns will have a

significant impact on treaty rights, resources, and cultural

practices for tribes, especially when considering Pacific

salmonid species.

Warmer water temperatures also have negative impacts

on shellfish harvest. Warm water may increase the

incidence of the harmful algal blooms that produce

toxins in shellfish. Although individual species respond

differently to environmental conditions, blooms of

one dinoflagellate responsible for paralytic toxins in

Puget Sound shellfish increase with warmer air and

water temperatures in Puget Sound.252 Projected future

conditions indicate that harmful algal blooms in Puget

Sound will become more frequent and will last longer.253

The largest and most toxic bloom ever recorded of

Pseudo-nitzschia, the marine algae that produces domoic

acid poisoning in shellfish and crabs, covered the West

Coast in the summer of 2015.254 Domoic acid can be

harmful or even fatal to humans if consumed. Levels

exceeded health safety standards, prompting closure of

shellfish harvests in Washington, Oregon, and California.

This was the largest closure of razor clam harvest and of

the multi-million-dollar crab fishery in Washington state

history. The toxin bioaccumulates in fish such as sardines

and anchovy that eat the algae and other plankton. This

in turn can poison other fish, birds, and marine mammals

such as sea lions. These blooms typically last only a

few weeks, but this one lasted from April through early

October and stretched from Santa Barbara, California, to

Alaska. The dinoflagellates that produce Paralytic Shellfish

Poisoning were also detected in some places in a rare

co-occurrence with domoic acid. A combination of warm

water and the availability of nutrients enabled the bloom.

Generally these two conditions do not occur together,

since the upwelling of cold, deep water is usually the

source for nutrients in the California Current Ecosystem,

which flows along the west coast of North America from

British Columbia to Baja California.

An analogy of the effect on marine life of warmer ocean

temperatures can be seen in an unusually long-lived and

exceptionally warm expanse of water that appeared

across the Gulf of Alaska in autumn 2013. By 2015, it

spanned the North Pacific from Alaska to Japan with water

temperatures at the sea surface as much as 7°F (3.9°C)

higher than average for months at a time. Several theories

have been proposed to explain this phenomenon,

nicknamed “the blob.” In the Gulf of Alaska it is related

to a persistent ridge of high atmospheric pressure that

reduced westerly winds in the autumn and winter of

2013 to 2014.255 This meant fewer and weaker storms in

the PNW and less mixing and cooling of surface ocean

waters. By January 2016, the warm blob had weakened,

due to strong winds from the north and cooler ocean

temperatures brought about by El Niño conditions in the

Pacific Ocean.256 However, temperature anomalies persist

down to a depth of about 980 feet (300 m), so impacts

to marine ecosystems and weather could continue for

some time.257

The warm-water blob is a phenomenon not seen before, and

while it may not be linked to climate change, it does provide

a life-size laboratory of the ecological effects of warm surface

water. The changes in wind patterns reduced the primary

production of the marine food web as phytoplankton biomass

plummeted in the winter of 2013–2014.258 The decrease in krill

and other plankton resulted in the starvation and death of sea

birds like Cassin’s auklets from California to British Columbia

between October 2014 and February 2015. Warm-water

species like sunfish, sardines, and certain types of jellyfish

appeared in uncharacteristic places. Salmon returns to Puget

Sound were particularly low in 2015 due to a combination

of warm ocean conditions and hydrological drought in the

region’s streams. Projections for 2016 were low enough to

prompt closure of many salmon fisheries.259

Observed and Projected Changes

The upper 2,300 feet (700 meters) of the global oceans

have been warming, with the greatest amount of warming

occurring in the upper 250 feet (75 meters). Since 1971 this

uppermost 250 feet has warmed about 1°F on average.

Records before that time are sparse, but it is likely that

warming was occurring during the first half of the 20th century

as well.260 Because the ocean has so much mass, and water

has a high heat capacity, the ocean can store vast amounts of

energy. Of all the heat absorbed by air, sea, and land since

1971, about 93 percent has been stored in the ocean. The

high heat capacity and slow circulation of the world’s oceans

means that while the surface ocean takes about a decade to

adjust to warming from GHG emissions, the deep ocean will

continue to warm for centuries or millennia.261

Average annual sea surface temperatures in the California

Current System warmed during the 20th century by about 1 to

2°F (0.6 to 1.0°C).262 In Puget Sound, long-term temperature

data is limited. Water temperature records from Hood Canal,

Admiralty Inlet, and Point Jefferson show an increase of 0.8 to

1.6°F from 1950 to 2009.263 At the Race Rocks Lighthouse in

the Strait of Juan de Fuca, the waters warmed by 1.7°F (0.9°C)

between 1921 and 2005.264

Oceans are projected to continue to warm, and this heat

will penetrate into the deeper oceans. The waters off the

Washington Pacific coast are projected to increase by

another 2°F by the 2040s under a moderate GHG emissions

scenario.265 Natural variability in our region from climate

phenomena like El Niño and the PDO will continue to play

a role, but how these short-term cycles will be affected is

Climate Change and Our Natural Resources

Sea level rise of the Pacific Ocean off the coast of Washington state is a significant concern of the

tribes. Photo: Debbie Preston, NWIFC.

not well known.266 In addition, the amount of warming in

any specific location may depend on circulation patterns

or topography. For example, shallow areas with minimal

circulation such as Lynch Cove in Hood Canal can be

susceptible to greater warming.267

5.4

SEA LEVEL RISE

The elevation of the sea surface varies geographically and

over time. It is controlled by a number of factors including

water density; the amount of water locked up globally in ice

caps, ice sheets, and glaciers; and changes in land surface

elevation. Warming oceans actually take up more space in

a process called thermal expansion, one of the main drivers

of sea level rise. Another global source of sea level rise is

the water released by the melting of the great ice sheets of

Antarctica and Greenland and of glaciers on land.

Thermal expansion and ice melt contribute to absolute

sea level rise, but relative sea level includes the effects of

vertical land movement. Upward land movement can occur

due to sediment accretion or plate tectonics causing uplift.

Downward land movement can also occur due to plate

tectonics or from subsidence due to sediment compaction,

organic material decomposition, or groundwater

withdrawal.268 Because these local conditions vary, the

amount of relative sea level rise is not consistent throughout

Washington. Vertical land movement in western Washington

is dominated by tectonic forces. The general trend along the

Pacific coast is tectonic uplift that increases toward the north,

and Puget Sound exhibits subsidence that increases to the

south, but these rates vary over time and location.269

Sea level rise changes coastal habitat types, which changes

the abundance and distribution of coastal species that have

A Report from the Treaty Tribes in Western Washington

specific tolerances for depth, frequency, and duration of

inundation.270 The number and types of invertebrates,

including but not limited to shellfish, can change. In just

one example, the Swinomish Indian Tribal Community

found that at least 27 percent of the shellfish harvest

area at Lone Tree Point is vulnerable to the effects of sea

level rise due to inundation of habitat.271 As more tribes

conduct sea level rise assessments, other tribal shellfish

harvest sites will be found to be vulnerable to sea level rise

as well. Sea level rise can also accelerate coastal erosion.

While the erosion of shorelines is a natural process that

plays a role in the formation and maintenance of many

types of shore forms, excess coastal erosion can change

the distribution and viability of biological communities in

the nearshore.

Many organisms spend the early part of their life in the

nearshore, including the larvae or juveniles of species

that have commercial and cultural importance to tribes,

such as salmon, Pacific herring, and Dungeness crab. The

nearshore encompasses the shoreline from the top of the

upland bank or bluff on the landward side down to the

depth of water that light can penetrate and where plants

can photosynthesize, called the photic zone. Marine

water, fresh water, and terrestrial landscapes interact

in a complex mosaic of habitats and processes in the

nearshore. For juvenile salmon, estuaries provide cover

from predators, sources of prey, places to wait out the

low tide, and opportunities for the physiological transition

that occurs in migration between freshwater and marine

environments.272 This is especially true for chinook, whose

overall survival rates decrease without estuary access,273

and for chum, whose estuarine rearing phase is a major

factor in the size of the adult population.274 The nearshore

is also critical for forage fish—the small, schooling fish that

act as a link in the marine food web between plankton

and the larger fish, birds, marine mammals, and squid that

prey upon them.

Impacts to the coastal environments of Washington occur in

the context of development and modification of shoreline

habitats over the past 150 years. These modifications

have disrupted natural habitat-forming processes with

destructive effects on ecological function and structure

in all segments of the nearshore. When the rate of sea

level rise is not too fast, nearshore ecosystems can adapt

by migrating upland to maintain the same amount of

tidal inundation, as long as the substrate is suitable.

Shoreline development prevents the landward migration

of nearshore habitat. This is known as coastal squeeze—

coastal habitats are hemmed in by rising water levels on

one side and hardened shorelines on the other. Habitat

is lost for birds, fish, shellfish, and plants. The narrowing

and loss of surf smelt habitat will probably be among the

first negative effects of climate change to the Puget Sound

nearshore.275 Coastal squeeze will also destroy marsh

habitat necessary for juvenile chinook and chum as they

migrate through estuaries. In modified shorelines, sea level

rise and storm surge can also expose sources of pollutants

that then enter the water and destabilize infrastructure such as

freshwater and sewer pipes, power transmission, and roads.

Saltwater intrusion associated with sea level rise can also cause

contamination of shoreline freshwater aquifers and can escalate

on-site septic system issues.

Observed and Projected Changes

Global mean sea level rise is estimated at 7.3 inches

(0.19 m ± 0.02 m) for the period between 1901 and 2010.276

Off the Washington coast, observations from satellite altimetry

and tide gauges indicate a long-term increase in sea level rise

with large seasonal and decadal variability.277 Estimates of

relative sea level rise based on analysis of tide gauge records

average 0.8 mm per year in Friday Harbor and 2.3 mm

per year in Seattle. In the northwest corner of the Olympic

Peninsula, upward vertical land movement outpaces sea level

rise, so relative sea levels are actually decreasing slightly in

the area (Table 1).278

Table 1: Observed relative mean sea level (MSL) trends in Washington. Since tide gauge measurements are made with respect to a local

fixed reference level on land, these measurements record relative MSL trends that combine the rates of global sea level rise and local

vertical land motion. Source: NOAA (2013)279 and Craig (1993, for Olympia).280

Location

Mean Sea Level

Historical Trend (mm/year)

100-Year Change Equivalent

(inches per 100 years)

Olympia

2.4

9.6

Seattle

1.99 +/- 0.16

7.8

Port Townsend

1.69 +/- 0.84

6.6

Port Angeles

-0.06 +/- 1.0

-0.2

Neah Bay

-1.76 +/- 0.31

-7.0

Toke Point (Willapa Bay)

0.35 +/- 1.01

1.3

Sea level is also influenced by storms and atmospheric

conditions. When large storms at sea move inland, a

storm surge can occur, especially when high astronomical

tides combine with a wind direction perpendicular to

the shore.281 Extreme ocean levels brought about by a

combination of storm surge, high tides, or El Niño events

occur regularly on the west coast of the United States.

El Niño storms commonly raise water levels 20 to 30 inches

(50 to 70 centimeters), and one extreme storm in March

1999 raised the tide almost 6 feet (1.75 meters) above the

predicted level.282 Rising sea levels can increase the effects

of storm surge, high tides, and high flows in rivers, leading

to extreme flooding.

Climate Change and Our Natural Resources

In the next decade, sea level rise will continue along the West

Coast but the amount varies among sources depending

on the type of analysis conducted. In addition, vertical land

motion is difficult to predict since it varies spatially and is not

necessarily consistent over time. Studies that combine low

rates of sea level rise with high rates of vertical uplift show that

some areas could see a decline in sea level.283 Other studies

indicate that sea levels in Washington state could increase by

a range of 4 inches to 4.6 feet by 2100.284

Projections of future sea levels also vary depending on the

level of GHG emissions and different estimates of the future

contribution of melting ice sheets. The rate of ice sheet melt

could vary depending on how quickly melting accelerates

as temperatures warm and what happens when substantial

parts of the ice sheets collapse. Recent studies have

concluded that the West Antarctica Ice Sheet has begun

to disintegrate and that there is enough water held

just in that section of ice to ultimately raise global sea

levels by 16 feet in the next few centuries.285 The future

behavior of the Antarctic Ice Sheet is not well known,

but temperatures in Antarctica are rising more quickly

than predicted and the topography of the seabed below

the ice, the presence of warm ocean currents, and the

configuration of the ice sheet all could contribute to

catastrophic and irreversible collapse. In addition, a

glacier that covers 16 percent of the Greenland Ice Sheet

has been receding three times faster since 2012, with an

additional 410 feet (125 meters) of retreat every year.286

Table 2: Comparison of sea level rise projections for Washington state relative to 2000.

2030 Sea Level Rise

Projection (inches)

2050 Sea Level Rise

Projection (inches)

2100 Sea Level Rise

Projection (inches)

Puget Sounda

(Mote et al. 2008)

+13

Seattleb

(USACE 2015)

+4.7

+8.3

+21.2

NW Olympic Peninsulaa

(Mote et al. 2008)

Port Townsendc

(Petersen et al. 2015)

+2.4

+4.8

+12

Port Angelesc

(Petersen et al. 2015)

+1.2

Neah Bay and Clallam Bay-Sekiuc

(Petersen et al. 2015)

-1.2

-2.4

-1.2

Central and South Pacific Coast of Washingtona

(Mote et al. 2008)

+11

Pacific Coast of Washingtond

(NRC 2012)

+2.6

+6.5

+24.3

Region

Puget Sound:

Olympic Peninsula:

Pacific Coast of Washington:

Medium sea level rise estimates relative to the end of the 20th century. No values for 2030 given.

High sea level rise scenario relative to 1992 levels.

Projections relative to 2000 for a high GHG emissions scenario at the 99% confidence limits using the probabilistic approach to sea level

rise developed by Kopp et al. (2014).287

Mean values at the latitude of Seattle relative to 2000 based on a high sea level rise scenario.

A Report from the Treaty Tribes in Western Washington

Taking Action: Storm Surge at the Quinault Indian

Nation Village of Taholah

The village of Taholah on the Pacific

coast of the Olympic Peninsula is

home to the Quinault Indian Nation’s

school, courthouse, police station,

and the homes of 700 tribal members.

The 2,000-foot-long sea wall built to

protect the village was breached by

storm waves in March 2014, causing

flooding, erosion, and property

damage. The tribe declared a state of

emergency and the sea wall was rebuilt

by the U.S. Army Corps of Engineers.

Taholah is still vulnerable; the wall

has been breached before and such

flood events are expected to increase

in frequency and severity. The village

of Taholah was partially evacuated in

December 2015 due to the possibility

of another sea wall collapse.288 In

response, the tribe has a plan to move

the entire village to upland property.

The move is estimated to cost $350

million and the tribe is exploring a

collaborative approach to funding.

Moves such as this can be difficult

because tribal culture and identity are

place-based and because of the painful

history of the forced relocation of

Native Americans. David Underwood,

a Quinault tribal member, told KUOW

Earthfix News in Seattle, “This place,

right here, where we are, is where my

people have lived for thousands of

years and each and every member of

this tribe, we’re all proud Quinault tribal

members, proud Native Americans. I

don’t ever want to leave this place, but

if the ocean keeps rising we’re going to

have to.”289

Quinault tribal member Sonny Curley canoes through Sea Breeze Field on the Quinault Reservation.

Photo: Larry Workman, Quinault Indian Nation.

Climate Change and Our Natural Resources

5.5

OCEAN ACIDIFICATION

Changing ocean chemistry has the potential to alter the range

and distribution of marine species along the Pacific coast.

The world’s oceans have absorbed about 30 percent of the

atmospheric CO2 emitted by humans.290 When CO2 dissolves

in seawater, it causes a sequence of chemical reactions that

leads to ocean acidification. The acidity of a substance is

measured by the concentration of hydrogen ions, or pH.

The lower the pH, the more acidic the substance. Because

pH is a logarithmic scale, each whole number increment

represents a tenfold difference. Ocean pH can vary widely

in time and space due to local factors. In Hood Canal, pH as

low as 7.39 has been measured.291 Where aquatic vegetation

is present, pH can fluctuate as plants take up CO2 during

photosynthesis during the day and release CO2 during

respiration at night. Besides pH, ocean acidification can also

be measured through the total dissolved inorganic carbon

in seawater and by the partial pressure of CO2, which is the

amount of CO2 dissolved in seawater.

The chemical processes that cause ocean pH to decrease

also reduce the saturation state of the minerals aragonite and

calcite, two forms of calcium carbonate that marine species

such as crabs, clams, oysters, and certain types of plankton

use to build their shells and skeletons. The saturation state is

a measure of the likelihood that a mineral will form or dissolve

in seawater. Low saturation states interfere with the ability of

organisms to form shells and dramatically lower their survival

rates. A meta-analysis of studies that measured biological

response to the projected changes in global mean surface

ocean pH by 2100, found that mollusk survival was reduced

by 34 percent, calcification by 40 percent, growth by 17

percent, and development by 25 percent.292

Tribal clam and oyster harvest areas are replenished by natural

recruitment of larvae or locally produced seed. If reproduction

of these species is hampered by ocean acidification, we

may have to explore other ways of keeping shellfish beds

viable. However, solutions such as obtaining seed from

hatcheries located in other regions might not be feasible for

some species such as crab. In addition, the shellfish that we

rely upon may not be available due to domoic acid, a toxin

that is harmful to humans and wildlife and that has caused

widespread shellfish closures on Washington beaches.

Laboratory experiments with the Pseudo-nitzschia diatoms

that produce domoic acid found that higher levels of CO2 in

the water resulted in greater growth rates and increased toxin

production in the diatoms.293

A Report from the Treaty Tribes in Western Washington

Each level of the marine food web, from plankton to fish

to mammals, is susceptible to changes in reproduction,

growth, and species distribution from changing ocean

chemistry. Phytoplankton response to increased ocean

acidification will vary, with some species spurred to grow

faster, while others will grow more slowly or die out.294

As calcifying species decline, they could be replaced

by non-calcareous species, changing the structure of

the marine food web. By 2100, the plankton species

distribution could be very different in response to

ocean acidification in combination with warmer ocean

temperatures.295 One type of calcifying zooplankton that

is already showing the impacts of ocean acidification

are the pteropods, tiny swimming snails that are a food

source for salmon, herring, and other fish. A 2011 study

of waters off the coasts of Washington, Oregon, and

California showed severe shell dissolution in 53 percent of

onshore pteropods and in 24 percent of those offshore.296

The authors estimate that the amount of severe shell

dissolution of pteropod shells in the region has doubled

since pre-industrial times due to ocean acidification.

Crustaceans such as Dungeness crab and spot prawns

are most vulnerable to ocean acidification as larvae and

juveniles because it can slow their growth. Laboratory

tests of Dungeness crab found that larvae took longer to

hatch and develop under pH 7.1, the projected future

condition during upwelling events.297 Under the low-pH

conditions, crab larval survival was reduced by more than

half relative to the open ocean pH of 8.0.298 Crab larvae

are important forage for marine finfish and a decline

in larvae could have ramifications through the marine

food web. Since crustaceans like crab use chitin along

with calcium carbonate for their shells, some species

may be buffered against the corrosive effects of ocean

acidification.299 This depends on species type, life history

strategy, the type of habitat they are accustomed to, and

the exact chemical composition of their exoskeletons. 300

Rockfish and flatfish could experience impacts due to

the decline of some of the echinoderms that they prey

upon.301 Larval fish show behavioral changes, such

as less effective predator detection and avoidance.302

As abundance of pteropods decline, the fish that

normally feed on them may turn to juvenile fish such as

salmon instead.303 Orcas are sensitive to changing ocean

conditions such as temperature, pH, DO, and shifts in

food web structure.304

Observed and Projected Changes

Before the industrial revolution, ocean pH averaged

8.2; today ocean pH is 8.1.305 The 0.1-unit drop in

pH represents a 26 percent increase in hydrogen ion

concentration.306 Our region is experiencing accelerated

rates of ocean acidification due to natural factors such as

cold water (which can absorb more CO2) and upwelling

ocean currents that bring deeper high CO2/low DO

waters to the surface. In addition, human activities can

increase local acidification through nutrient pollution from

agricultural runoff carried by rivers, failing septic systems,

and wastewater treatment plants. Nutrients stimulate

phytoplankton growth and when those organisms

die, their decomposition by bacteria lowers dissolved

oxygen, pH, and aragonite saturation state. The rate of

decomposition is accelerated by increased sea surface

and air temperatures.

The pH of surface waters in Puget Sound and the Pacific

coast has decreased between 0.05 to 0.15 units since the

dawn of the Industrial Age.307 Overall in Puget Sound, 24

percent of the pH decrease in the summer and 49 percent

of the decrease in the winter can be attributed to ocean

acidification.308 The amount of undersaturated water

in the top 328 feet (100 meters) of the ocean off the coasts

of Washington, Oregon, and California has increased by 6

times since the pre-industrial era (Figure 9).309 Marine waters

entering Puget Sound were above saturation for aragonite in

pre-industrial times, but today they are undersaturated. 310

Models indicate that the surface of the global oceans will

continue to acidify as atmospheric CO2 continues to rise.

Water at depth will also acidify as CO2 in surface waters

penetrates deeper into the ocean. By the end of the 21st

century, the global mean surface ocean pH is projected to

decrease by 0.31 to 0.5 units for high emissions scenarios.311

Seasonal cycles of the ocean’s dissolved inorganic carbon

and pH in seawater are projected to cause large-scale

undersaturation of aragonite if atmospheric CO2 reaches

496 ppm above the North Pacific and 511 ppm above the

Southern Ocean.312 In Washington, seasonal upwelling

and upland sources of nutrients and organic carbon will

continue to promote more acidification of coastal waters.

The combination of ocean acidification and warmer ocean

temperatures creates a stronger response together in

biological factors such as calcification, photosynthesis,

reproduction, and survival.313

Figure 9: Percent of the upper 100 m of the water column

off the U.S. Pacific coast estimated to be undersaturated

with aragonite (a form of calcium carbonate used by marine

organisms to form shells): during pre-industrial times (left)

and from August to September 2011 (right). Numbers in

the squares denote pteropod monitoring stations. Source:

modified from Bendaršek et al. 2014.314

Climate Change and Our Natural Resources

Taking Action: Makah Tribe Ocean Acidification Research

The Makah Tribe is using a novel

approach to an established scientific

method to detect the effects of ocean

acidification in Neah Bay. The analysis

of stable carbon and oxygen isotopes

in fish otoliths (or ear bones) has been

used to track the fish’s life histories and

their environmental conditions. At the

Makah Tribe, analysis of carbon isotope

ratios (13C/12C or δ13C) in bivalve

shells is helping the tribe to make

informed decisions about shellfish

resource protection and economic

development. Previous research

based on eight years of observation

of pH at Tatoosh Island in Neah Bay

concluded that the pH decline is

proceeding 10 times more quickly

than expected and that the decline has

ecological consequences for nearshore

ecosystems.315 However, people living

on the Makah Reservation have noticed

that modern mussels are different in

size and shape between Neah Bay,

Makah Bay, and Tatoosh Island

(Figure 10). Because these locations

are within five miles of one another and

share similar water characteristics, it is

possible that the different growth rates

of California mussels in Neah Bay may

come from the different food sources

or supplies. Along with samples of

California mussels from Neah Bay,

Makah Bay, and Tatoosh Island, the

tribe conducts water quality monitoring

for temperature, salinity, pH, dissolved

oxygen concentration, and the isotope

ratios of dissolved inorganic carbon

and oxygen.

Figure 10: California mussel samples were collected from three locations: (1) Wa’adah Island; (2) Tatoosh Island; and (3) Strawberry

Rock. These locations represent the different environmental conditions where mussels grow in Neah Bay. Source: Makah Tribe.

A Report from the Treaty Tribes in Western Washington

5.6

COASTAL HYPOXIA

Ocean acidification is occurring alongside warmer ocean

temperatures and lower levels of dissolved oxygen.

All three of these stressors on marine organisms are

expected to increase as the climate changes.316 As in

fresh water, warmer salt water can hold less dissolved

oxygen. Hypoxia (low dissolved oxygen) and anoxia

(the lack of dissolved oxygen) in marine waters can have

a profound effect on ecological processes and fisheries.

Fish and shellfish need oxygen and will change their

behavior when levels decrease. Mobile species will leave

a hypoxic area in search of more oxygenated waters,

but if mobility is low or when levels drop too low or too

quickly, “fish kills” can occur. Lower dissolved oxygen also

reduces growth, reproduction, and availability of prey

and habitat.317 Low oxygen supply can lower the tolerance

of some species to high temperatures and their defense

against disease.318

The amount of dissolved oxygen in the marine waters of

the PNW naturally varies throughout the day, seasonally,

and annually. Hypoxic conditions regularly occur in some

locations in Puget Sound, particularly in Hood Canal and

the southern inlets.319 This is often primarily due to natural

factors, such as circulation patterns that result in slow

flushing rates in some areas. On the Pacific coast, strong

winds from the north can push surface waters offshore

causing upwelling of deeper, low-oxygen ocean water.

Human sources of nutrients also lower dissolved oxygen

levels and increase ocean acidification. The combination

of hypoxia and ocean acidification can be highly stressful

to organisms.

While some marine species are adapted to periodic

hypoxia, other species cannot tolerate such conditions.

A number of fish kills have occurred in Hood Canal in the

last 15 years, predominantly affecting copper rockfish and

lingcod.320 In 2006, an exceptionally large and longlasting hypoxic event struck the Pacific coast of Oregon

and much of Washington, stretching across about 1,160

square miles (3,000 km2), encompassing 80 percent of

the water column in shallow shelf waters and persisting

from June to October.321 Surveys conducted that August

in Oregon waters found that the rocky reefs that normally

support diverse species of rockfish were completely

devoid of fish.322

Observed and Projected Changes

Oxygen levels in global oceans are decreasing. This is due in

part to warming ocean temperatures. Warmer waters hold less

oxygen and also increase stratification, where ocean layers

mix less and oxygen in surface waters does not descend into

deeper waters. Warm water also encourages the growth of

phytoplankton, which depletes dissolved oxygen at depth

during decomposition.

The frequency and severity of hypoxic events are increasing

in the California Current Ecosystem due to changes in the

oxygen levels in upwelling water, the intensity of winds that

cause upwelling, and increases in productivity and respiration

of marine plants and phytoplankton.323 This is placing added

pressure on fish populations that are already stressed by loss

of habitat, pollution, warmer oceans, and ocean acidification.

One study of the relative influence of ocean acidification,

hypoxia, and temperature in global ocean ecosystems

found that the variation in species diversity is most strongly

explained by oxygen levels.324

By 2030, the climate change signal will be evident in hypoxia

around the world’s oceans.325 The dissolved oxygen levels in

the North Pacific have been decreasing for the last 50 years.

The continuation of this trend combined with increased

nutrients from human sources, warming ocean temperatures,

and changes to the timing and amount of freshwater inputs

will cause widespread decreases in dissolved oxygen levels in

Puget Sound and the Strait of Juan de Fuca.326 Low dissolved

oxygen will cause habitat fragmentation and reduction in

habitat for some species.327

5.7

RESILIENCE IN COASTALAND

MARINE ENVIRONMENTS

The resilience of coastal environments to sea level rise and

storm surge is greatly enhanced by the presence of salt

marshes and coastal wetlands. Natural shorelines improve

coastal resilience by allowing landward migration of habitats

and by maintaining the geomorphic processes that build

and sustain nearshore ecological function. The natural

topographical and hydrological variability in coastal wetlands

also improves ecosystem function.328

Human modifications that alter natural geomorphic and

hydrological function can reduce the resilience of nearshore

environments. The presence of shoreline armoring structures

such as bulkheads can limit the natural ability of the beach to

Climate Change and Our Natural Resources

Eelgrass and kelp are vital to the coastal ecosystem as habitat and food for marine species. Photo: Tiffany Royal, NWIFC.

adjust to changes in sea level, increase wave energy scour,

and block the delivery of sediment from upland sources.

Levees and revetments in river systems can also detract from

nearshore geomorphic function. For example, the levees that

currently constrain the lower Skagit River concentrate flows

enough to push a substantial amount of the sediment carried

by the river past the delta into the deeper waters offshore.

The presence of distributary channels on the Skagit River delta

would allow river flows to spread sediment across the delta

where it can build up the ground surface as sea levels rise.329

Eelgrass meadows and kelp beds play an important role

in the coastal ecosystem as habitat and food for marine

species and they may be able to enhance the resilience

of coastal species to ocean acidification at the site scale.

As they photosynthesize, they decrease the amount

of CO2 dissolved in seawater locally. The presence of

eelgrass and kelp could provide refuge from corrosive

waters for coastal species. Eelgrass and salt marshes also

provide carbon sequestration—that is, they store carbon

in their leaves and in the substrate.

Although ocean acidification is a global process, local

conditions can vary greatly. Spatial variability along with

individual species characteristics may buffer some locations

from the corrosive effects of ocean acidification.330 Because

high-CO2, low-DO conditions occur regularly in our region,

some species are naturally resilient to a limited amount of

exposure to these conditions. However the combination

of ocean acidification, warmer ocean temperatures, and

decreasing levels of dissolved oxygen will work together to

reduce resilience of species, particularly those that are not

mobile and cannot move away from adverse conditions.

Changing marine food webs will have variable effects

on marine mammals. Generalist species such as gray

whales, Pacific harbor seals, and California sea lions may

be able to adapt to new or different food sources and

changing habitat.331 Other species are more vulnerable,

such as the northern fur seal populations, which are

declining in part due to changing climate.332 The ESAlisted southern resident orca populations that spend

spring, summer, and autumn in the Salish Sea are also

vulnerable to decreases in the availability of Pacific

salmon, their major food source.333

A Report from the Treaty Tribes in Western Washington

Taking Action: Lummi Nation Wetland and Habitat Mitigation Bank

The coastal wetlands of the Lummi

Indian Reservation form where rivers

and streams meet the sea. They

provide vital ecosystem goods,

functions, and services, including

stormwater attenuation, floodwater

storage, water quality enhancement,

fish habitat, wildlife habitat, and plants

with traditional cultural importance.

Protecting and enhancing coastal

wetlands and the functions they

provide has become increasingly

important in the face of global climate

change—particularly accelerated sea

level rise. The tribe has developed the

Lummi Nation Wetland and Habitat

Mitigation Bank to protect and improve

function on large tracts of estuarine

and floodplain wetlands of the Lummi

and Nooksack rivers. In 2009, the

Lummi Nation approved an acquisition

and land use plan for approximately

2,770 acres of wetland habitat on

the reservation’s riverine and coastal

floodplains for mitigation banking and

restoration purposes. These areas will

be protected into perpetuity through

conservation easements.

The mitigation bank will be developed

in phases. The first phase, which

encompasses most of the Nooksack

River estuary, became operational

in 2012. Enhancement activities

underway in this area include removing

invasive species and planting native

species (e.g. willows, conifers). At

the Lummi River estuary sites, where

acquisition of properties is ongoing,

rehabilitation will focus largely on

restoring direct tidal input to areas that

have been isolated from tidal hydrology

by shoreline dikes. Restoration at

these sites will include removing

existing tide gates or replacing

them with self-regulating tide gates,

removing portions of existing dikes,

and opening remnant sloughs and

distributary channels—actions which

will facilitate shoreward migration and

help to prevent coastal squeeze. By

implementing this extensive wetland

protection and enhancement project,

the Lummi Nation has taken an

important step to guard against coastal

wetland losses due to climate change.

Lummi tribal technicians plant conifers

in the Nooksack delta where the tribe is

enhancing habitat for a wetland mitigation

bank. Photo: Kari Neumeyer, NWIFC.

Climate Change and Our Natural Resources

6. TERRESTRIALAND

UPLAND ENVIRONMENTS

6.1

CHAPTER SUMMARY

Terrestrial environments provide us with an abundant array

of wild game, greens, roots, nuts, berries, and other fruit.

Terrestrial plants and animals are also used for medicine,

ceremony, and artistic expression. Terrestrial ecosystems

are responding to warmer air temperatures, less snowpack,

higher snowlines, more frequent and severe flooding, shifts

in precipitation patterns, and drier summers. These changes

occur within the context of human land and water use that

already have diminished the quantity, connectivity, and

ecological integrity of vital habitat for terrestrial animal and

plant species.

The impacts of climate change to terrestrial ecosystems

include:

·· Changes to species ranges as they migrate to higher

elevations and latitudes;334

·· Decreased productivity due to temperature or drought

stress;335

·· Changes to the timing of key life cycle events tied to

temperature or other climate variables and subsequent

changes in species interactions;336

·· Increased frequency and size of wildfires;337

·· Escalating disease, parasite loads, pest populations,

and invasive species; and338

·· Greater probability of disturbance from landslides.339

6.2

THE TREE OF LIFE

Many plants have foundational importance to tribes.

For example, the western red cedar has been called the

Tree of Life because of its contributions to all areas of tribal

life.340 Along with its commercial value, western red cedar

is used in making regalia items, baskets, canoes, paddles,

rattles, vests, hats, drums, masks, and totem poles.341

The cedar is regarded as sacred and is used for ceremony,

prayer, and healing. Because of its importance and potential

vulnerability to climate change, western red cedar has been

identified as a key concern for the Jamestown S’Klallam Tribe

in their Climate Vulnerability Assessment and Adaptation

Plan.342 Yellow cedar, although rare on the western Olympic

Peninsula, is highly valued by the Treaty of Olympia tribes for

commercial use and for carving canoe paddles and masks.343

A Report from the Treaty Tribes in Western Washington

Every type of vegetation found in the terrestrial

environment has a traditional use: trees, flowering

plants, ferns, fern allies (horsetails and clubmosses),

mosses, liverworts, lichens, and fungi. Working

collaboratively, the Tulalip Tribes, the Muckleshoot

Indian Tribe, the Suquamish Indian Tribe, King County,

and the Burke Museum of Natural History and Culture

at the University of Washington have been researching

the nutritional value of traditional foods. Archaeological

excavations of 130 sites in King, Kitsap, and Snohomish

counties have found over 280 kinds of plants and

animals that were used as far back as 5,000 years ago.

Unfortunately, many of these species are difficult to obtain

today as the environment has become urbanized. At

the community roundtable discussion for the Traditional

Foods of Puget Sound Project in 2009, one family

recounted that one of the most abundant prairie areas

for camas bulb harvest had been paved over for a

housing development.344

“In the Squaxin Island Tribe of the Medicine

Creek Nation it was common for our people

to live beyond 100 years old. Tribal elders

attribute this longevity to knowledge about

traditional foods and medicines that was

passed down from generation to generation.

Their powerful traditional science included

understanding techniques for gathering,

knowing when was the most potent time to

harvest, how food was processed for everyday

use and how plants were used for ceremonial

purposes. This knowledge was highly

regarded as a sacred gift that contributed to

living a long and fulfilling life.”

– Charlene Krise, Tribal Council Secretary, Squaxin

Island Tribe345

Foods such as roots, greens, and berries provide vital

nutrients recognized for their antioxidant and immune

system supporting roles. Big huckleberry formed a

major part of traditional diets for many PNW tribes due

to its high yield, sweetness, and nutritional content.

Berry gathering was one of the main reasons for extended

trips into the mountains in the summer. Berries were

smoked or dried in the sun and preserved for use all year.

Specific berry grounds belonged to women or their

families and a network of trails connected the fields.346

Students in the Chief Kitsap

Academy’s Lushootseed

Language and Culture class learn

how to weave traditional hats and

baskets using dried cedar strips

harvested by tribal members.

Photo: Tiffany Royal, NWIFC.

Today, most of the huckleberry habitat is on public,

federally owned lands, which can sometimes limit access,

despite treaty-protected rights to gather. In the past

century, management practices like fire suppression have

caused huckleberry meadows to decline or disappear.

Wild game includes deer, elk, mountain goat, black

bear, rabbit, waterfowl, wild turkey, mink, beaver, and

river otter. Tribal hunting practices have strong spiritual

underpinnings. Deer and elk are essential foods at

potlatches, funerals, and naming ceremonies. Their

hooves and antlers are used for ceremonial tools and

clothing, as is the wool of mountain goats. Wildlife

provides a stable source of high-quality protein on

reservations where unemployment rates are high and

some tribal members struggle to feed their families.

The importance of traditional foods to our health and

well-being underscores the central role of protecting

and restoring ecosystem health.

We have always actively managed our terrestrial hunting

and gathering grounds. Our forebears maintained highly

valued gathering areas through controlled burns, planting

seeds, transplanting bulbs and plants, pruning, harvest

rotation, and redirecting water pathways.347 Prairies were

intentionally preserved from forest incursion for plants like

camas, notably in the south Puget Sound region,348

but also on the Olympic Peninsula on the Quillayute Prairie.349

Controlled burns maintained biodiversity and helped create

a mosaic of habitat types.350 The fires were carefully managed

to prevent them from spreading beyond the targeted area.

The fire practitioners were skilled at understanding and

predicting weather conditions and finding the optimal time

for burning.351 Fire was used to enhance big huckleberry

harvest, since it sprouts well after fire and produces more fruit

when the tree canopy is not completely closed.352 Burning

was also used to enhance the quality and quantity of basketry

materials like bear grass, beaked hazelnut, and willow.

Keeping meadows and clearings open also promoted forage

for deer and elk.

In the PNW, commercial timber production on tribal lands

began in the late 1800s and continues to this day. Douglas

fir and western hemlock are dominant species for timber

harvest. Following a period of Bureau of Indian Affairs

controlled forestry on reservation lands, the 1975 Indian

Self-Determination and Education Assistance Act enabled

tribes to establish our own natural resources departments

and independent forestry programs.353

Climate Change and Our Natural Resources

6.3

SHIFTS IN VEGETATION RANGES

Many terrestrial plants and animals are shifting their

geographic distributions to higher latitudes or higher

elevations due to climate change. At the same time, plants

and animals may be unable to migrate if their rate of dispersal

cannot keep pace with the rate of change in environmental

conditions or if their distribution is limited by other factors,

such as light.354 The impacts to tribes could be enormous

if traditional resources die off or move out of established

gathering areas and become inaccessible to tribal members.

Traditional practices built around certain plants and animals

may not be easily transferred to the species of the new

ecosystems that arise in a changing environment.

Forests play an important role in tribal life and in Washington

state overall. Forests comprise 52 percent of the total area of

Washington, with 56 percent publicly owned by federal and

state agencies and the rest under tribal, private, and corporate

ownership. Conifer species dominate the forest ecosystems,

but hardwood species are abundant in riparian areas and in

disturbed sites after avalanches or logging.355 Along with

these species, forest ecosystems include understory species—

an array of woody shrubs, herbaceous plants, ferns, mosses,

lichens, and fungi.

Observed and Projected Changes

In the long term, the composition of plant species present

in forest ecosystems depends on the topography, soil type,

moisture availability, type of precipitation (snow or rain),

temperature, and length of the growing season. As snow

cover declines and melts earlier, high elevations will be

snow-free for longer periods. Some species may be able to

expand into those areas. For example, trees may be able to

encroach into existing meadows, especially wet mountain

meadows, where temperature, snow cover, and moisture will

no longer limit tree establishment.356

While vegetation models for the forests west of the Cascade

Mountains show that the forest type will shift from conifer

to mixed conifer-deciduous, responses to changing

environmental conditions vary among species and locations.357

The moist maritime forests of the west side North Cascades

are projected to shift to the dry temperate forest types seen on

the east side of the mountains, but not all tree species will be

able to make the transition and areas suitable for lodgepole

pine will decrease.358 In models with increased temperatures

and changing precipitation, the high elevation ecosystems of

A Report from the Treaty Tribes in Western Washington

the Olympic Peninsula do not respond uniformly because

of local variations in topography and the rain-shadow

effect of the mountains. In the wet southwest region of the

peninsula, the models show forest communities shifting

toward higher elevations, but in the dry northeast the same

future conditions result in an entirely new combination of

tree species.359

Shifts in plant species take time and depend on the ability

of each species to disperse their seeds. In the rainforests

of British Columbia, tree species such as Sitka spruce and

western hemlock that are widespread and genetically

diverse are better able to colonize new habitats, while

other species like cedars and many understory plants may

not be able migrate as quickly.360 Dispersal ability plays

an important role in the sensitivity of a number of tree

species to climate change. An assessment of tree species

that are important to the Treaty of Olympia tribes on the

Pacific coast (Quinault Indian Nation, Quileute Tribe, and

Hoh Tribe) classified western white pine, western red

cedar, Douglas fir, Pacific yew, and lodgepole pine as

moderately sensitive to the impacts of climate change.361

Although Sitka spruce was found to be able to colonize

new habitats in B.C., the Treaty of Olympia assessment

rated its sensitivity to climate change as moderately high.

Sitka spruce is restricted to coastal areas that have cool,

foggy summers and it is sensitive to disturbances and

changes in temperature and precipitation patterns. In the

southern parts of its range, even small decreases in fog

and air moisture in the summer could have severe effects

on survival and reproduction, especially in combination

with pest outbreaks and disturbances such as wildfire and

windstorms.

These changes can bring about cascading effects through

ecosystems as species relationships shift, and they can

create new communities, called novel ecosystems.

Douglas fir is a widespread and economically important

species. Conditions projected for 2060 indicate that

about 32 percent of current Douglas fir habitat would

be lost, mainly due to low elevation water shortfalls

(Figure 11).362 However, Douglas fir may be able to

spread into high elevation areas made accessible by

warmer temperatures and less snow, so the overall

amount of area covered would not change greatly,

provided there is enough water.363

Figure 11: Change in areas of Washington

where the climate will be suitable for

Douglas fir by the 2060s. The map colors

indicate the percentage of statistical models

that suggest the climate will support

Douglas fir, so orange areas are at greatest

risk while dark green areas are at the lowest

risk. Note that the decline is centered

at lower elevations and that in western

Washington decline is most widespread

in the south Puget Sound region a

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