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Title:
Top 10 Principles for Designing Healthy Coastal Ecosystems Like the Salish Sea
Author:
Gaydos, Joseph K.; Dierauf, Leslie; Kirby, Grant; Brosnan, Deborah; Gilardi, Kirsten; Davis, Gary
E.
Publication Date:
2008
Publication Info:
Postprints, UC Davis
Permalink:
http://escholarship.org/uc/item/8df9m840
DOI:
10.1007/s10393-009-0209-1
Abstract:
Like other coastal zones around the world, the inland sea ecosystem of Washington (USA)
and British Columbia (Canada), an area known as the Salish Sea, is changing under pressure
from a growing human population, conversion of native forest and shoreline habitat to urban
development, toxic contamination of sediments and species, and overharvest of resources. While
billions of dollars have been spent trying to restore other coastal ecosystems around the world,
there still is no successful model for restoring estuarine or marine ecosystems like the Salish Sea.
Despite the lack of a guiding model, major ecological principles do exist that should be applied
as people work to design the Salish Sea and other large marine ecosystems for the future. We
suggest that the following 10 ecological principles serve as a foundation for educating the public
and for designing a healthy Salish Sea and other coastal ecosystems for future generations: (1)
Think ecosystem: political boundaries are arbitrary; (2) Account for ecosystem connectivity; (3)
Understand the food web; (4) Avoid fragmentation; (5) Respect ecosystem integrity; (6) Support
nature’s resilience; (7) Value nature: it’s money in your pocket; (8) Watch wildlife health; (9) Plan
for extremes; and (10) Share the knowledge.
Top 10 Principles for Designing Healthy Coastal Ecosystems
Like the Salish Sea
Joseph K. Gaydos,
1
Leslie Dierauf,
2
Grant Kirby,
3
Deborah Brosnan,
4
Kirsten Gilardi,
5
and Gary E. Davis
6
1
The SeaDoc Society, UC Davis Wildlife Health Center, Orcas Island Office, 942 Deer Harbor Road, Eastsound, WA 98245
2
Regional Executive for the Northwest Area, United States Geological Survey, 909 First Avenue, Suite #800, Seattle, WA 98104
3
Northwest Indian Fisheries Commission, 224 Stewart Road, Suite 175, Mt. Vernon, WA 98273
4
Sustainable Ecosystems Institute, P.O. Box 80605, Portland, OR 97280
5
The SeaDoc Society, UC Davis Wildlife Health Center, School of Veterinary Medicine, 1 Shields Avenue, Davis, CA, 95616
6
GE Davis & Associates, 204 Los Padres Drive, Westlake Village, CA 91361
Abstract: Like other coastal zones around the world, the inland sea ecosystem of Washington (USA) and
British Columbia (Canada), an area known as the Salish Sea, is changing under pressure from a growing human
population, conversion of native forest and shoreline habitat to urban development, toxic contamination of
sediments and species, and overharvest of resources. While billions of dollars have been spent trying to restore
other coastal ecosystems around the world, there still is no successful model for restoring estuarine or marine
ecosystems like the Salish Sea. Despite the lack of a guiding model, major ecological principles do exist that
should be applied as people work to design the Salish Sea and other large marine ecosystems for the future. We
suggest that the following 10 ecological principles serve as a foundation for educating the public and for
designing a healthy Salish Sea and other coastal ecosystems for future generations: (1) Think ecosystem:
political boundaries are arbitrary; (2) Account for ecosystem connectivity; (3) Understand the food web;
(4) Avoid fragmentation; (5) Respect ecosystem integrity; (6) Support nature’s resilience; (7) Value nature: it’s
money in your pocket; (8) Watch wildlife health; (9) Plan for extremes; and (10) Share the knowledge.
Keywords: coastal ecosystem health, Georgia Basin, marine, Puget Sound, restoration, Salish Sea
INTRODUCTION
The inland sea of Washington State (USA) and British
Columbia (Canada) is recognized as an international
treasure (Fraser et al. 2006). Corresponding to the ancestral
home of the Coast Salish people and often referred to as the
Salish Sea (Fraser et al. 2006), the ecosystem stretches from
Olympia in the south to Campbell River in the north and
extends from the crest of the surrounding mountain ranges
(Olympic, Cascade, Vancouver Island, and Coast Range) to
the deepest part of the marine waters (Figure 1). The area
south of the international border is called the Puget Sound
Basin, and to the north, the Georgia Basin (Figure 1).
Thousands of streams and rivers drain 7470 km of coastline
into 16,925 square kilometers of marine water (1:250,000
scale World vector Shoreline and TEOPO2 topographic/
bathymetric GIS grid). In addition to nearly 7 million
people, the region is home to over 200 species of marine
Published online: March 4, 2009
Correspondence to: Joseph K. Gaydos, e-mail: jkgaydos@ucdavis.edu
EcoHealth 5, 460–471, 2008
DOI: 10.1007/s10393-009-0209-1
Original Contribution
2009 The Author(s). This article is published with open access at Springerlink.com
and anadromous fish, over 100 species of marine birds, 26
species of mammals, and thousands of invertebrate species
(Puget Sound Partnership 2006; Brown and Gaydos 2007;
Puget Sound Action Team 2007). Like other coastal zones
around the world, the Salish Sea has been dramatically
altered under pressure from a growing human population,
conversion of native forest and shoreline habitat to urban
development, toxic contamination of sediments and spe-
cies, and overharvesting of resources (Thom and Levings
1994; Puget Sound Action Team 2007).
Washington State Governor Christine Gregoire
recently initiated a statewide effort to restore the Puget
Sound portion of this ecosystem by the year 2020 (Puget
Sound Partnership 2006). Similar efforts have been
undertaken in other estuarine and coastal regions of the
United States and around the world. However, despite
billions of dollars spent on ecosystems such as the
Chesapeake Bay or Florida Everglades, their restoration
remains a distant goal (Finkl and Charlier 2003; Powledge
2005).
Figure 1. Map outlining the
boundaries of the Salish Sea (solid
black line), from the mountain
tops to the marine water, showing
terrestrial topography, marine
bathymetry, and the ‘‘arbitrary’’
international border (white-gray
dotted line) separating the Puget
Sound Basin (United States) to
the south and the Georgia Basin
(Canada) to the north.
Designing a Healthy Salish Sea 461
Efforts at ecosystem restoration generally look back-
ward in time, attempting to reconstruct complex, dynamic,
self-organizing systems of living and non-living elements.
The challenge is that conditions that existed prior to the
present might never reoccur or could be impossible to
recreate as species are extirpated, invasive species are
introduced, and atmospheric and oceanic conditions
change. We suggest that it is more appropriate to talk about
designing future ecosystems that reflect current societal
values and use what we know of ecological principles to
guide the design process.
The concept of health provides a flexible, overarching
framework for designing ecosystems. We agree with the
definition proposed by the Puget Sound Partnership (2006)
that defined a healthy ecosystem as a place where:
•Fish and shellfish are plentiful and safe to eat, air is
healthy to breathe, and water and beaches are clean for
swimming and fishing;
•People are able to use and enjoy the lands and waters of
the region, tribal cultures are sustained, natural resource-
dependent industries such as agriculture, tourism, and
fisheries thrive, and the region is economically prosper-
ous; and
•The rich diversity of species flourish and are supported
by plentiful, productive habitat, as well as clean and
abundant water.
Rebuilding a healthy Puget Sound and Salish Sea is an
exercise in place-based ecosystem management. Place-
based conservation strategies require that stewards know
and understand the ecosystem, restore impaired resources,
protect the ecosystem, and connect people wholeheartedly
to the place (Davis 2005). Educating local citizens, scien-
tists, businesses, and policymakers to ‘‘know, protect, and
connect’’ to the Salish Sea will require a comprehensive
strategy built on sound ecological principles that can serve
as a foundation for the process. Using well-accepted eco-
logical principles to educate society improves upon efforts
of other ecosystem restoration educational efforts that
provide citizens with lists of things to do without educating
them on a guiding ecological rationale.
We propose 10 fundamental ecological principles to
serve as a guiding framework for designing a healthy coastal
ecosystem like the Salish Sea. These imperatives are
designed to form a basis for educating and energizing
policymakers and citizens in the concepts of place-based
management. While this article is focused on the Salish Sea,
the ecological principles are applicable to other ecosystem-
based restoration efforts around the world.
THE 10 PRINCIPLES
Think Ecosystem: Political Boundaries
Are Arbitrary
Although there is a major statewide effort to restore Puget
Sound by the year 2020 (Puget Sound Partnership 2006),
the Puget Sound basin is only one half of a large and
unified ecosystem, the Salish Sea (Fraser et al. 2006). Efforts
to restore Puget Sound will fail if they do not incorporate
and integrate similar efforts on the Canadian side of the
border. The international political boundary separating the
Puget Sound and Georgia Basin is invisible to marine fish
and wildlife; species listed as threatened or endangered
under the US Endangered Species Act (ESA) or the Cana-
dian Species at Risk Act, including Southern Resident killer
whales (Orcinus orca), marbled murrelets (Brachyramphus
marmoratus), and some ecologically significant units or
species of Pacific salmon (Onchorynchus spp.), traverse the
boundary daily (Brown and Gaydos 2007). Oceanographic
processes such as freshwater inflows and wind-driven sur-
face currents exchange biota, sediments, and nutrients
throughout the larger ecosystem. For example, the less
saline, more buoyant Fraser River plume can be observed
by satellite imagery flowing across the international
boundary throughout the year (Wilson et al. 1994), and
tidal oscillations move huge volumes of water across the
border four times daily (Thomson 1981).
International, state, provincial, or tribal, political
boundaries impede ecosystem restoration. Management of
the iconic Pacific salmon is a striking example of the un-
ique challenges created when ecosystem and political
boundaries do not align. The migration patterns of the five
species of Pacific salmon in this ecosystem create trans-
boundary fishery regimes containing mixed stocks from
numerous river systems of origin (some from the USA and
others from Canada). In 1945, the United States and
Canada implemented the first bilateral Pacific salmon-
sharing agreement, followed by the 1985 Pacific Salmon
Treaty. However by 1997, as salmon stocks were declining,
accusations from both sides about the interception and
harvest of fish destined for the other country became so
heated that the USA and Canada independently shifted
their fishery regimes, foregoing all concerns about stock
462 Joseph K. Gaydos et al.
declines. These ‘‘salmon wars’’ ultimately culminated in
a renewed salmon harvest agreement signed in 1999
(Ruckelshaus et al. 2002).
While the governments of Washington State and
British Columbia signed an Environmental Cooperative
Agreement in 1992 to work together on marine issues in the
Salish Sea (British Columbia/Washington Marine Science
Panel 1994) the agreement is hampered by internal con-
straints imposed by tribal and federal laws. For instance, a
1974 court decision reaffirmed the treaties between the U.S.
Federal Government and 19 tribes in Washington signed in
1885, and ruled that 17 tribes with usual and accustom
fishing areas in Puget Sound have the right to 50% of the
harvestable fish and shellfish resources (Boldt decision 384
F. Supp. 312; 1974 U.S. Dist. LEXIS 12291). By contrast, in
Canada, the Federal Government regulates all tribal harvest.
‘‘Thinking ecosystem’’ requires focusing restoration
efforts from the start on all sides of the political border and
finding mutually agreeable solutions among all levels of
government. The principle worked in the design of the
Mount Elgon Regional Ecosystem Conservation Program, a
transboundary natural resource management program
involving the republics of Kenya and Uganda (Muhweezi
et al. 2007), and will work for multi-national coastal eco-
systems as well. Focus on the ecosystem as its own legiti-
mate entity can help prevent the past experiences where
agreements made when resources were abundant quickly
unraveled as those resources declined.
Account for Ecosystem Connectivity
Ecosystems are more interconnected than most people
appreciate. Citizens, scientists, managers, and policymakers
filter out these connections in order to focus on specific
areas or species of interest, using compartmentalization to
simplify the daunting challenges of managing complex
systems.
Understanding the connectivity and linkages between
seemingly unrelated species and ecosystems is key to suc-
cessful restoration. Like most ecosystems, the factors
determining the fate of the Salish Sea extend hundreds of
kilometers from the sea to the crest of the mountains that
surround these waters (Figure 1). For example, the amount
and configuration of impervious surfaces (e.g., concrete
parking lots, roads) and harvested forests impact the biotic
integrity of streams feeding into the Salish Sea (Alberti et al.
2007), which, in turn, affects the health of the entire
ecosystem. Forest health impacts the abundance of the
marbled murrelet, an endangered seabird that nests up to
50 miles inland in old growth forests, but spends the
remaining 11.5 months of the year feeding at sea (Raphael
2006). Intricate food webs can connect species across eco-
systems. For example, gray whale (Eschrichtius robustus)
abundance is linked to productivity in the Bering Sea
(Calambokidis et al. 2002); the abundance of migrating
gray whales feeding in the Salish Sea could be important for
the recovery of declining surf scoter (Melanitta perspicilla-
ta) populations (Anderson and Lovvorn 2008).
Commerce and transportation are powerful non-bio-
logical forces that link the biota of Puget Sound to other
ecosystems. For instance, in 2006–2007 Washington State
and tribal fishermen harvested over 225 metric tons of sea
cucumbers (Parastichopus californicus), the majority of
which were exported to Asian markets [M. Ulrich,
Washington Department of Fish and Wildlife, personal
communication]. Increasing non-local demand for fisheries
can potentially drive unsustainable harvests and hinder
restoration. The robust shipping industry that links the
Salish Sea to most of the world also is a source of invasive
species that can threaten the integrity of biological com-
munities (Ruiz et al. 2000).
Connectivity contributes to ecosystem functions, and
understanding these intricacies is important for designing
healthy ecosystems. For example, recent modeling suggests
that the mangrove-based ontogenetic migrations of par-
rotfish could, through a trophic cascade on macroalgae,
enhance the recovery rate of midshelf Caribbean coral reefs
from hurricanes (Mumby and Hastings 2008). Conse-
quently, preserving or replanting mangroves will improve
Caribbean coral resiliency in the face of predicted increased
hurricane frequency and intensity (Knutson et al. 2001).
While it is tempting to filter out the apparent ‘‘noise’’ from
other species and ecosystems, acknowledging and identi-
fying key cross-species and cross-habitat connections are
essential to understanding changes in the system and
measuring performance.
Understand the Food Web
Food webs represent complex trophic interactions among
species; they can change seasonally and geographically
(Paine 1980). Although often simplified for communica-
tion purposes, food web linkages are complex, subtle, and
interactive; they play a major role in ecosystem connec-
tivity, as well as in ecosystem resiliency and capacity for
renewal.
Designing a Healthy Salish Sea 463
A working food web model is a powerful tool for
managing ecosystems. Around the world, traditional har-
vest management tools, such as maximum sustainable yield
models, focus on how many individuals can be harvested
sustainably by humans. However, the models fail to take
into account the full range of trophic interactions and
trophic needs (Struhsaker 1998; Walters et al. 2005). For
example, an acceptable salmon harvest level is designed to
ensure that sufficient individuals are left to spawn in order
to maintain viability of the salmon run into the future.
What it fails to account for are the needs of other species
dependent on the same salmon run, i.e., those species that
prey on salmon (e.g., whales) or those species that are
salmon prey. Determining the impact of human-harvested
salmon on killer whales, eagles, or any of the other 136
vertebrate species that rely on salmon or salmon carcasses
(Cederholm et al. 2000) has proved elusive. Yet it has
important biological and policy consequences. For
instance, an important factor in listing Southern Resident
killer whales as threatened under the ESA was the decline in
its primary prey, salmon (Brosnan 2006).
Food webs can be used to identify priority or key species
in biological communities. Measures taken to protect them
and their habitats benefit the entire ecosystem. For instance,
Pacific sand lance (Ammodytes hexapterus) and surf smelt
(Hypomesus pretiosus) are key forage fish for some Puget
Sound birds and mammals (Davoren and Burger 1999;
Robards et al. 1999; Lance and Thompson 2005). Locating
and protecting their intertidal gravel-sand spawning beaches
and associated upland riparian habitats assures food sup-
plies for many species. Human alteration of the shoreline
can change environmental conditions of these beaches and
halve egg survival (Rice 2006), resulting in ‘‘bottom up’’
impacts on the ecosystem through the food web.
Knowledge of food web dynamics allows managers to
monitor movement of contaminants in the ecosystem
(Ross et al. 2004) and the effects of the toxins on species
composition, abundance, diversity, and ultimately, the food
web itself. Bioaccumulation of toxins has been shown to
impact multiple species in many ways, from the immu-
nologic health of harbor seals (Ross et al. 1996) to the
density and species richness of Phoxocephalid amphipods
(Swartz et al. 1982).
Avoid Fragmentation
Human activities that break otherwise contiguous habitat
(land and seascapes) into smaller pieces fragment ecosys-
tems, reduce their ecological integrity, and threaten their
capacity to renew themselves (Soule
´and Lease 1995;
Vitousek et al. 1997). Habitat is the place where species
interact and form complex communities. Habitat size is
directly linked to population size and the nature of species
interactions. All species require a minimum number and
density of individuals to persist (Shaffer 1981), thus they
also require a minimum amount of suitable habitat. For
most species, habitat configuration is also important
(Hovel 2003). When habitats are fragmented, and shrink
below the size required to support a minimum viable
population or are significantly modified or disturbed, a
sequence of events begins that can end with species
extinction. At low densities (associated with small habitats),
individuals may be unable to find mates (the Allee effect).
For example, this is particularly critical for benthic animals
with little mobility such as abalone and some rockfish
species (Davis et al. 1998; Yoklavich 1998). Small popula-
tions are more susceptible to extinction by extreme natural
events and are more likely to lack the genetic diversity
needed to adapt to changing physical and biological con-
ditions (Tilman and Downing 1994), such as climate
change or competition from invasive species.
Unlike the terrestrial environment, where habitat size
is visible and easily monitored, fragmentation in the marine
environment is notoriously hard to study. Thus, it has
received far less attention. Steneck et al. (2002) point to
several ways in which people inadvertently fragment marine
habitats. For instance, seafloor trawling can have devas-
tating effects on the seafloor and result in isolated ‘‘islands’’
of unaltered submarine habitats too small to maintain
viable populations. Pelagic species and large mammals can
experience habitat fragmentation through fisheries and
reserve policies. For instance, reserve areas may be too
small to contain the necessary food resources to sustain
populations of marine mammals.
Where the land meets the ocean, anthropogenic
shoreline alterations can fragment the nearshore marine
habitat and reduce productivity. For example, terrestrial
insects falling into nearshore marine water are an important
food source for migrating juvenile salmonids; the removal
of overhanging shoreline vegetation reduces this important
food source (Brennan and Culverwell 2004). Additionally,
removal of overhanging shoreline vegetation can alter the
microclimate of beaches and reduce their suitability for
incubating eggs of intertidal spawning fish (Rice 2006).
Some tools used to address ecosystem fragmentation in
terrestrial ecosystems also could be used to address eco-
464 Joseph K. Gaydos et al.
system fragmentation in coastal ecosystems. Fragmentation
through land subdivision and the loss of large-scale
dynamic processes such as wildlife migrations and fire was
identified as the major threat to the world’s grassland
ecosystems (Curtin and Western 2008). Cultural exchange
between Masai pastoralists from Kenya and ranchers from
the United States helped address these fragmentation
threats by speeding up understanding and adaptation
(Curtin and Western 2008).
Respect Ecosystem Integrity
Intact ecosystems are more than the sum of their parts.
Processes and forces that bind the parts into a system
produce synergies and properties that the individual parts
do not possess when simply collected together. Ecological
integrity, in which a system has all its parts and no ‘‘extra’’
ones, is a hallmark of environmental health (Leopold
1949). An intact ecosystem has a complete suite of species,
and a full range of size and age classes of each component
species.
Ignoring the ecological integrity and the power of
biological interdependence in marine systems has been
catastrophic. Historically, fishery practices targeted preda-
tors and preferentially removed old, large organisms (those
with the greatest reproductive capacities; Berkeley et al.
2004), while relying on smaller, rapidly growing and barely
reproducing younger animals for replenishment (Pauly
et al. 1998). As a consequence, fishery collapses became
widespread. But the ecosystem-wide impacts were just as
disastrous. Because predators mediate competition among
prey species (Paine 1969) and help assure that a few, fit
individuals of all kinds survive to produce another gener-
ation, such single-species management strategies not only
doomed targeted populations to death spirals, but also
triggered trophic cascades with ecological effects that per-
sisted for decades and involved hundreds of species (Day-
ton et al. 1995; Jackson et al. 2001).
Adding, or introducing, invasive species, toxic mate-
rials, and pathogens also reduces ecological integrity. In the
Salish Sea, non-native species like the purple varnish clam
(Nuttallia obscurata) likely were introduced in ballast water
(Dudas 2005). Other species, like the Japanese seaweed
Sargassum muticum, likely were introduced with the
intentionally introduced Pacific oyster (Crassostrea gigas),
and now compete with native kelp, impacting benthic
subtidal communities (Britton-Simmons 2004). The ocean,
a historical out-of-sight–out-of-mind dumping ground for
industrial waste, now bears the burden of tonnes of orga-
nochlorines and other persistent organic pollutants that
have bioaccumulated in the food chain and impacted the
health of top predators (Moss et al. 2006). The Salish Sea’s
resident and transient killer whales are considered some of
the most contaminated cetaceans in the world (Ross et al.
2000).
Support Nature’s Resilience
A resilient ecosystem can rebound after a disturbance.
Resilience is a measure of health and indicates how much
stress a system can absorb before it permanently changes
into an alternative state or collapses (Holling 1973,1986;
Gunderson 2000). While resilience is essential in a healthy
ecosystem, it is frequently ignored in conservation plan-
ning. This is because it is hard to measure, and often only
recognized once the system is on the verge of collapse.
Biological communities have several natural attributes
that make them resilient in the face of change and distur-
bance. For example, the presence of a keystone species
determines persistence and stability (Paine 1969; Estes et al.
1989; Walker 1995; Walker et al. 1999), and in the Salish
Sea’s rocky intertidal zone, the sea star Pisaster ochraeus is
essential to maintaining a highly diverse and stable com-
munity. In their absence, a monoculture of mussels
(Mytilus spp.) occurs (Paine 1969). Other communities
lacking a keystone species rely on a suite of interacting
organisms to build resilience (e.g., Tilman and Downing
1994; Walker 1995; Carpenter and Cottingham 1997;
Walker et al. 1997,1999; Gunderson 2000). Genetic
diversity has also been shown to increase ecosystem resil-
ience in seagrass (Zostera marina) communities stressed by
elevated temperatures (Reusch et al. 2005).
Human actions can inadvertently disrupt the factors
that allow ecosystems to respond and persist in the face of
change. Removal of a keystone species can lead to ecosystem
collapse (e.g., Estes et al. 1989). Overfishing can have a
detrimental impact on resilience: 20 years of data from
reserve versus fished sites showed that reserves maintained a
greater complement of species, and were consistently able to
withstand and rebound from extreme, but not unusual,
environmental conditions such as El Nin
˜o years. Fished
(non-reserve) sites had fewer species and communities and
habitats within the fished sites (e.g., kelp forests) frequently
collapsed during El Nin
˜o events (Lafferty and Behrens 2005).
The principle of building ecosystem resilience is gain-
ing ground. Hughes et al. (2005) highlight the international
Designing a Healthy Salish Sea 465
emergence of a complex systems approach for sustaining
and repairing marine ecosystems, linking ecological resil-
ience to governance structures, economics, and society.
Previously, several authors (e.g., Hughes et al. 2003) noted
that corals in the Indo-Pacific and elsewhere are showing
signs of resilience in their ability to adapt to climate change
and called for international integration of management
strategies that support reef resilience. Since then, toolkits
on effective ways to build reef resilience as an integral part
of designing healthy marine ecosystems have been devel-
oped and are being applied worldwide on reefs from India
to Africa, the Caribbean, and the Americas (see http://www.
reefresilience.org).
Value Nature: It’s Money in Your Pocket
Economics is the allocation of limited resources among
alternative, competing ends; it is about what people want,
and what they are willing to give up in exchange (Daly and
Farley 2004). Human well-being is derived from access to,
and often the marketing of, essential ecological goods and
services provided by ecosystems. These include fossil fuels,
minerals, wood, fish, meat, edible plants, watchable wild-
life, biofiltration of contaminants, and a multitude of other
ecological ‘‘inputs.’’ While higher values of waterfront
properties are considered luxuries, most ecological goods
and services are considered basic needs for human survival.
Despite the complexities of economic globalization,
healthy ecosystems support economic prosperity and well-
being (Srinivasana et al. 2008). The Salish Sea provides the
people who live in the region with abundant natural capital
which contributes substantially to the financial prosperity
of the region. In Washington alone, marine fish and
invertebrates support commercial fisheries worth $3.2 bil-
lion a year; the ports of Seattle and Tacoma enable over $70
billion in international trade; and water activities such as
sailing, kayaking, whale-watching, and SCUBA diving
generate 80% of all dollars spent on tourism and recreation
in the state every year (Puget Sound Partnership, unpub-
lished data).
Healthy ecosystems support economic prosperity.
Unhealthy systems cost money to repair and in lost
opportunity to benefit from the natural capital. Overhar-
vesting, pollution, and loss of wild habitat reduce the
quality and quantity of ecosystem services and, ultimately,
the economic potential of a region (Clausen and York
2007). Fecal coliform contamination of nearshore waters
closed a third of Washington’s $97 million shellfish beds to
harvest in 1 year alone (Puget Sound Action Team 2007;
Pacific Coast Shellfish Growers Association 2008). In the
Salish Sea, ecosystem services provided by higher trophic
species like salmon and killer whales, which generally dis-
appear before those provided by species lower in the food
chain (Dobson et al. 2006), are decreasing. The cumulative
economic and ecosystem services losses associated with the
depletion of these higher trophic species is incalculable, but
likely astronomical.
When appropriately balanced, ecosystem services can
be used to simultaneously advance conservation and
human needs, as has been shown with projects like Quito,
Ecuador’s Water Fund, China’s Sloping Lands Program,
Kenya’s Il’Ngwesi Ecolodge, and Namibia’s Conservancy
Program (Tallis et al. 2008). A healthy Salish Sea that
provides services such as plentiful and safe fish and shell-
fish, clean water, natural resource-dependent industries, is
money in our pockets. Ecosystem services provide revenue
from the marine-based industries that are the lifeblood of
the region’s economy, and mean less spent on major repairs
to reverse ecological damage. Decision-makers and citizens
working to restore ecosystems around the world need to
grasp nature’s economic benefits or they will grossly
underestimate the full benefits of a restored ecosystem
while overestimating the relative costs of restoring it.
Watch Wildlife Health
Disease in marine wildlife can serve as a sentinel for human
health. Animals, particularly wildlife, are thought to be the
source of over 70% of all emerging infections (Chomel et al.
2007). A burgeoning human population, increased travel
opportunities, booming commerce, frequent animal relo-
cations, and expanding aquaculture increase human expo-
sure to zoonotic diseases from marine wildlife (Friend 2006).
Blooms of the phytoplankton Pseudo-nitzschia have
caused closures of recreational, commercial, and tribal
subsistence shellfish harvest in the Salish Sea (Trainer et al.
2006). These organisms produce domoic acid, a biotoxin
known to cause seizures and death in marine mammals and
amnesic shellfish disease in humans (Van Dolah et al.
2001). Marine mammals are exposed by eating fish that
have consumed domoic acid (Lefebvre et al. 2002). Exposed
animals often will strand on beaches and can serve as an
early warning indicator for potential exposure of humans
through shellfish consumption (Van Dolah et al. 2001),
thereby allowing managers to close shellfish harvesting
areas to protect human health.
466 Joseph K. Gaydos et al.
Discovering that the feline parasite Toxoplasma gondii
infected marine wildlife alerted people to the fact that raw
shellfish consumption also could be a route of exposure for
humans. If a pregnant woman becomes infected with this
parasite, the parasite can infect the fetus, leading to mental
retardation, seizures, blindness, and death in children
(Alvarado-Esquivel et al. 2006). Interestingly, this cat par-
asite has been discovered to infect marine wildlife, such as
sea otters (Enhydra lutris; Conrad et al. 2005), marine-
foraging river otters (Lontra canadensis; Gaydos et al. 2007),
and harbor seals (Phoca vitulina; Lambourn et al. 2001). It
is believed that marine wildlife are exposed to T. gondii
when cats shed the infective stage (oocyst) in feces, which is
then transported by freshwater run-off into the marine
ecosystem (Miller et al. 2002). Increased numbers of
domestic and feral cats and their associated feces (Dabritz
et al. 2006), as well as modifications in freshwater run-off
(Miller et al. 2002), have probably increased marine
mammal exposure to this parasite. Because shellfish can
concentrate the infective T. gondii oocysts (Arkush et al.
2003), humans, like marine mammals, also are at risk for
exposure by eating uncooked shellfish.
Human, wildlife, and ecosystem health are intimately
connected. Understanding and monitoring diseases in both
groups will help to identify where and when a stressed
ecosystem is contributing to increased disease in people
and wildlife, and how the ecosystem can be redesigned. In
the Salish Sea region, high-quality public health programs
exist, but efforts to monitor and understand marine wildlife
health in both countries are limited and not well linked to
human health networks. In many less-developed parts of
the world, both human and wildlife health need to be better
studied and incorporated into designing healthy ecosys-
tems.
Plan for Extremes
Knowing that the daily average temperature is 71F has
little meaning if the daily temperature ranges from 115F
during the day and 27F at night. We all know the perils of
walking across a river with an ‘‘average depth of 4 feet.’’
Planning for the extremes, and not just the average, is
prudent.
High variation and diversity are key characteristics of
living systems, and averages can mislead people seeking to
understand and manage nature. For instance, fisheries
management based on ‘‘average abundance’’ will fail to
account for poor years, and is likely to drive the species
extinct. Yet resource users often will prefer to manage for
the average.
A major discovery of environmental science in the 20th
Century was the ecological significance of ‘‘natural extreme
events.’’ Many people still view these kinds of events only as
disasters that wreak havoc on society and cause humani-
tarian tragedies (Kumar et al. 2005). The emergence of
disturbance ecology (e.g., Connell 1978; Paine and Levin
1981) illustrated the critical roles that rare extreme events
like wildfires, hurricanes, droughts, floods, and El Nin
˜o
Southern Oscillation events have played in sustaining bio-
diversity and ecological integrity in oceans (Dayton and
Tegner 1984). As citizens, scientists, and decision-makers
begin to envision a restored Salish Sea, that vision must
include policies, laws, and management actions that ac-
count for extreme but natural events.
Share the Knowledge
Humans are integral parts of ecosystems. Citizens who
understand that their own physical, mental, and economic
well-being is intimately connected to the health of the
ecosystem are more likely to support and engage in eco-
system restoration. While the people of the Salish Sea are
believed to value their ecosystem, in reality there currently
seems to be little support for restoring it. Despite over-
whelming scientific evidence about declines in the health of
Puget Sound, a 2006 poll found that only 8% of respon-
dents felt the condition of the environment was the most
important problem facing people in the Puget Sound
region (Puget Sound Partnership, unpublished data).
Widespread public education about the issues and what is
at stake could build a connection to the ecosystem and rally
support for its restoration.
But public support alone will not restore the Salish Sea.
Political leadership and funding are equally essential. In the
Florida Everglades, citizens have expressed their desire for
ecosystem restoration to their political representatives, and
the representatives themselves are charged with providing
the long-term support and funding required for restoration
(Kiker et al. 2001). Only an educated and dedicated polit-
ical leadership, demonstrating vision and stamina, will keep
a long-term focus on restoring ecosystems in the face of
numerous short-term competing interests.
Marine resources of the Salish Sea are managed by
multiple local, state, federal, tribal, and national govern-
ments. The common bonds among these myriad of gov-
ernance agencies is the human community they serve and
Designing a Healthy Salish Sea 467
the ecosystem they seek to sustain as healthy and produc-
tive. Scientists play a unique role in linking citizens, poli-
ticians, and nature. By sharing knowledge, they can help
inform citizens and decision-makers so that actions are
science-based and take account of the key factors that will
help ensure success.
MOVING FORWARD
The issues people face in designing a healthy Salish Sea are
not unique. Human communities worldwide gather in ever
increasing numbers at the coast, adding pressure on the
ecosystem’s goods and services. Human use threatens the
sustainability of the natural, social, and economic values
that attracted them to the coast in the first place (Martı
´nez
et al. 2007). Ocean and aquatic systems generate more than
60% of the world’s ecosystem services (Costanza et al.
1997). Human communities ignore or degrade these ser-
vices and their value at their own peril.
These 10 ecological principles can guide people in
designing local actions that will have persistent global im-
pacts on environmental quality and human health and well-
being. These science-based principles will be most effective
in informing political processes if they are communicated to
citizens and policymakers in ways that are both tangible and
memorable (Figure 2). Societies around the world that have
cultural, religious, and economic differences are working to
design healthy ecosystems. Expressing ecological principles
in ways that might capture the attention and interest of local
communities (e.g., Figure 2) will benefit place-based edu-
cation and conservation efforts.
In summary, issues at political boundaries can be
resolved with cooperation, while nature’s boundaries are
immutable, dynamic connections that cannot be negotiated
or changed by policy; think ecosystem. Great thinkers and
philosophers from Henry David Thoreau to Edward O.
Wilson have espoused the global interdependence of people
and other parts of nature that is inescapable in designing
sustainable communities; account for ecosystem connec-
tivity. Knowing how plants and animals are related to each
other by their diets is a practical way to visualize connec-
tivity, interdependence, and system integrity and helps
predict how nature will respond to stresses; understand
your food web. Habitats of adequate size and quality to
support high levels of biodiversity are critical characteristics
of healthy ecosystems; avoid fragmentation. Loss of integ-
rity threatens nature’s stability, beauty, and capacity for
self-renewal, but integrity can be rebuilt and sustained by
design; respect ecosystem integrity. While healthy ecosys-
tems have tremendous capacity for self-renewal, resilience
can be overwhelmed by collective human activities. Again,
resilience can be restored by people, by design. Healthy
ecosystems are money in your pocket because they save on
Figure 2. Top 10 ecological prin-
ciples translated into a format
intended to capture the attention
of, and be meaningful to, people
living in and around the Salish
Sea.
468 Joseph K. Gaydos et al.
repair costs and deliver essential goods and services; value
nature. Diseases in marine animals are closely linked to
human health and can provide early warnings as sentinels
of ecosystem stress; watch wildlife health. Nature is variable
and rarely average, and remember, extreme natural events
test fitness, mediate competition, and assure diverse
opportunities; plan for extremes. Finally, people matter
from grassroots to government, and little will happen
without educating and incorporating humans at every level
into designing a healthy ecosystem for the future; share the
knowledge.
ACKNOWLEDGMENTS
This manuscript was prepared thanks to the private
donations that support the SeaDoc Society (http://www.
seadocsociety.org), a program of the Wildlife Health Cen-
ter; the Wildlife Health Center is a center of excellence at
the UC Davis School of Veterinary Medicine. The United
States Geological Survey, the Northwest Indian Fisheries
Commission, the Sustainable Ecosystem Institute, and GE
Davis & Associates provided in-kind contributions of time.
We thank Norm Maher for creating the map of the Salish
Sea, Miguel Arboleda for his design of the cartoon figure,
‘‘The Ten Commandments of Coastal Ecosystem Design,’’
Alison Kent for graphics assistance, and two anonymous
reviewers for providing helpful comments that improved
the quality of the manuscript.
OPEN ACCESS
This article is distributed under the terms of the Creative
Commons Attribution Noncommercial License which
permits any noncommercial use, distribution, and repro-
duction in any medium, provided the original author(s)
and source are credited.
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