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Transcript
Marine Ecosystem-based Management in Practice: Scientific and Governance
Challenges
Author(s): MARY RUCKELSHAUS, TERRIE KLINGER, NANCY KNOWLTON, and DOUGLAS P.
DeMASTER
Source: BioScience, 58(1):53-63. 2008.
Published By: American Institute of Biological Sciences
DOI: http://dx.doi.org/10.1641/B580110
URL: http://www.bioone.org/doi/full/10.1641/B580110
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Articles
Marine Ecosystem-based
Management in Practice:
Scientific and Governance
Challenges
MARY RUCKELSHAUS, TERRIE KLINGER, NANCY KNOWLTON, AND DOUGLAS P. D E MASTER
Ecosystem-based management (EBM) in the ocean is a relatively new approach, and existing applications are evolving from more traditional
management of portions of ecosystems. Because comprehensive examples of EBM in the marine environment do not yet exist, we first summarize
EBM principles that emerge from the fisheries and marine social and ecological literature. We then apply those principles to four cases in which large
parts of marine ecosystems are being managed, and ask how including additional components of an EBM approach might improve the prospects for
those ecosystems. The case studies provide examples of how additional elements of EBM approaches, if applied, could improve ecosystem function.
In particular, two promising next steps for applying EBM are to identify management objectives for the ecosystem, including natural and human
goals, and to ensure that the governance structure matches with the scale over which ecosystem elements are measured and managed.
Keywords: fisheries, marine food webs, marine ecosystem-based management, marine ecosystems, ocean zoning
M
arine ecosystems are complex adaptive systems
linked across multiple scales by flow of water and
species movements (Levin and Lubchenco 2008). Despite
their adaptive character and often redundant linkages, marine
ecosystems are vulnerable to rapid changes in diversity and
function (Palumbi et al. 2008). Observable, widespread
declines in the status of species, habitats, and ecosystem function in the marine environment have led to calls for ecosystembased management (EBM) as a solution for what ails the
oceans (POC 2003, USCOP 2004). The argument that EBM
could maintain ecosystem structure—thus allowing the
ecosystem to maintain redundancies and resilience to environmental change—is appealing, yet not well tested. Why is
there growing consensus that EBM is a promising approach
for managing oceans? In short, marine ecosystems are in
trouble, indicating that many previous attempts to manage
individual threats in the absence of a system-wide approach
have not worked.
Dramatic declines in some marine species caused by overfishing provide striking examples of failed management practices and ineffective governance in the face of imperfect
scientific knowledge (Lotze et al. 2006, Hilborn 2007). These
high-profile failures in single-species fisheries management
led, in the mid-1990s, to efforts by the US Congress to
mandate improvements in governance and a broader, more
ecological approach. For example, Congress required that
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Fishery Management Plans identify habitat essential for the
productivity of a species or stock (i.e., “essential fish habitat”).
Essential fish habitat and other habitat-based approaches
have the potential to offer protection for more than just a
focal species, but their ancillary benefits to nontarget species
are not well understood.
In the late 1990s, academic scientists, natural resource
agencies, and nongovernmental organizations began to
promote the use of networks of marine protected areas
(MPAs) as a management tool to help address the problem
of uncoordinated, piecemeal approaches to protecting marine
species and habitats (US White House 2000, Lubchenco et al.
2003). The objectives of MPA networks include the enhancement of fisheries yields and protection of marine species
and communities. Within their boundaries, effective MPA
networks incorporate linkages among habitats that meet the
Mary Ruckelshaus (e-mail: [email protected]) is with the NOAA
(National Oceanic and Atmospheric Administration) Northwest Fisheries
Science Center in Seattle, Washington. Terrie Klinger is with the School of
Marine Affairs at the University of Washington in Seattle. Nancy Knowlton
is with the Center for Marine Biodiversity and Conservation at Scripps
Institution of Oceanography in La Jolla, California. Douglas P. DeMaster is
with the NOAA Fisheries–Alaska Fisheries Science Center in Seattle. © 2008
American Institute of Biological Sciences.
January 2008 / Vol. 58 No. 1 • BioScience 53
Articles
biological requirements of multiple species throughout their
life-history stages (e.g., Sala et al. 2002); such networks may
increase the resilience of systems to large-scale threats. Consequently, MPA networks can contribute as one tool within
an ecosystem-based approach to ocean management, but
they are not appropriate management tools for all species (e.g.,
highly migratory species) or all potential factors contributing to species declines (e.g., nonindigenous species, pollution,
social phenomena; Hilborn et al. 2004). Finally, MPAs may not
be effective in restoring the abundance of target species in the
face of global threats such as climate warming and disease
(Jones et al. 2004).
Two national panels recently reviewed the status of US
oceans and concluded that marine resources should be managed with a comprehensive, ecosystem-based strategy (POC
2003, USCOP 2004). The panels suggested that such a strategy should balance the interests of diverse stakeholder groups,
consider the status of both target and nontarget species, incorporate networks of MPAs to protect habitats and their
associated biota, and adopt an overarching system of ocean
zoning to coordinate regulation of human activities in particular areas at particular times. At the core of most descriptions of EBM approaches is the fundamental importance of
considering factors that drive human behavior and the choices
we make regarding our use of and interactions with marine
resources (USCOP 2004, Rosenberg and McLeod 2005).
The EBM concept has received a good deal of attention in
theory (NRC 1996, 2006), and has been adopted in principle
by some entities charged with managing ocean resources
(e.g., NMFS 1999). However, examples of comprehensive
approaches to marine EBM are rare. The dearth of cases
most likely reflects incomplete scientific information and
the difficulties inherent in implementing large-scale management strategies within the complex natural and socioeconomic systems characteristic of ocean governance.
If EBM applications in the oceans are rare, estimates of success, or feedback on what approaches are likely to succeed in
achieving ecosystem objectives, are rarer still. Although implementation of the full complement of EBM principles in the
ocean is in its infancy, there are regional cases that essentially
are “learning by doing” through management of portions of
ecosystems towards a subset of ecosystem objectives. This
growing number of management applications can help us see
the way forward. In this article, we illustrate how a few guiding principles borrowed from marine ecological, fisheries, and
socioeconomic theory can be combined with case studies to
develop a fuller application of EBM in marine environments.
Guiding principles for putting marine
EBM into practice: Case examples
Implementing an EBM approach in the ocean requires us to
think broadly. Broadening the scope of any EBM plan for the
oceans will require considering food-web interactions, drivers
of ecosystem function, and how human activities interact
with species and ecosystem services. On the basis of existing
guidance from national and international fisheries manage54 BioScience • January 2008 / Vol. 58 No. 1
ment organizations (NMFS 1999, FAO 2003), a combination
of ecological and socioeconomic theory, and lessons from existing test cases in marine environments, we summarize six
basic principles that characterize EBM approaches in the
oceans (box 1; POC 2003, USCOP 2004). Our objective here
is to illustrate how some of these general principles are being
used in partially developed EBM approaches in four specific
marine and coastal areas around the world. The examples
we offer illustrate how ecological principles have been
combined with considerations of human use patterns to design improved management approaches that constitute the beginnings of a comprehensive EBM strategy for marine species
and habitats. In each setting, we specify additional EBM principles that might be included to achieve broader ecosystem
objectives.
The waters of the Southern Ocean
surrounding Antarctica
Ecosystem-based fishery management has been practiced in
the waters surrounding Antarctica since the early 1980s, but
management in the region currently lacks comprehensive
ecosystem objectives, indicators, and management strategies
to incorporate the full ecosystem consequences of the fisheries
into a broader context (box 2). The Southern Ocean waters
are highly productive, and fisheries for marine mammals, fish,
and invertebrates have been in operation there for about two
centuries. Since 1982, management of Antarctic marine resources has been regulated by the Commission for the Conservation of Antarctic Marine Living Resources (CCAMLR),
whose membership consists of representatives of Antarctic
Treaty nations, and whose mandate is to conserve the Antarctic marine ecosystem. The CCAMLR has pioneered an ecosystem approach to fisheries management. The goal of this
approach is to avoid significant adverse impacts both on target species and on nontarget ecosystem components that are
dependent on fished species or affected by fisheries in other
ways, for example, through trophic interactions or bycatch
(Kock 2000, Constable 2001). The primary species groups
included in the Antarctic marine ecosystem are krill and
other zooplankton, squid, finfish, wide-ranging seabirds such
as petrels and albatrosses, penguins, and marine mammals
such as seals and toothed and baleen whales (figure 1). All of
these species groups either have been directly commercially
harvested or have suffered incidental mortality due to fishing
activities (Constable 2004). The CCAMLR’s mandate is to
coordinate the management of all marine species in the
Southern Ocean ecosystem, except for seals south of 60°S
and whales, which are covered under different management
agreements (CCAMLR 2006).
The krill fishery illustrates the CCAMLR’s approach to
ecosystem-based management. Krill (Euphausia superba) is
an important forage species for Antarctic predators, and also
has become an important commercial species. In response to
concern over high harvest rates, the CCAMLR developed
and used models to determine sustainable rates of krill
removal. These rates were then modified to account for the
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Box 1. Six basic principles for using an ecosystem-based management
framework to manage marine resources.
1. Define the spatial boundaries of the marine ecosystem to be managed.
The spatial extent of the ecosystem determines which species, other ecosystem attributes, and human activities are the focus of
management. So-called large marine ecosystems already have been delineated on the basis of large-scale biological, geomorphological,
and hydrological features (see the figure below; Sherman 1995). The US Commission on Ocean Policy further recommends including
watersheds that affect nearshore ecosystems within their boundaries (USCOP 2004). Because sociopolitical feedbacks and variation in
ecosystem responses to environmental conditions may occur at smaller spatial scales than those over which large-scale ecological
processes operate (Hutton and Leader-Williams 2003, Adger et al. 2005), nesting several ecosystem management efforts within larger
ecosystems may be advisable.
2. Develop a clear statement of the objectives of ecosystem-based management (EBM).
What biological and social values are desired from an ecosystem? For example, one aim of EBM could be to maximize overall ecosystem
yield and benefits to society of total fishery harvests (Hilborn 2007). Alternatively, the objective of EBM could be to reach target levels of
ecosystem services such as nutrient cycling or toxics filtering and ecosystem properties such as resilience in ecosystem dynamics,
biodiversity, redundancy, and modularity (e.g., Rosenberg and McLeod 2005, Levin and Lubchenco 2008, Palumbi et al. 2008). Working
through a deliberative political process to get broad agreement on the objectives helps tremendously in subsequent discussions about
how to achieve ecosystem goals.
3. Include humans in characterizations of marine ecosystem attributes and indicators of their response to change.
There is growing consensus among biologists and policymakers that including human uses of and interactions with natural resources in
EBM approaches improves the likelihood of achieving desired ecosystem outcomes (POC 2003, USCOP 2004, Hennessey and Sutinen
2005, Hilborn 2007). It is important to be clear in articulating what natural- and human-system attributes of the ecosystem best indicate
the status of the desired objectives so that progress can be tracked over time and adjustments in strategies can be made as needed (e.g.,
Adger et al. 2005, Livingston et al. 2005).
Large Marine Ecosystems of the World
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January 2008 / Vol. 58 No. 1 • BioScience 55
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Box 1. (continued)
4. Use a variety of strategies to hedge against uncertainty in the ecosystem response to EBM approaches.
Unanticipated effects of EBM on ecosystems can come from inherent variability and complexity in food-web dynamics, their interaction
with complex socioeconomic systems, and the uncertainty in the effects of alternative management approaches themselves. Regardless
of the state of models or analysis used to characterize a system, adopting a management approach that becomes relatively more
prescriptive over time as information (and thus certainty in outcomes) increases is one way to explicitly build in learning to strategy
development (e.g., Kaufman et al. 2004). Another prudent approach that can be implemented without extensive knowledge of a system
is including a diversity of regulation, reward, and other incentive systems for human behaviors that are consistent with EBM objectives
(Hutton and Leader-Williams 2003, Hilborn 2007). Where information allows, exploring and modifying alternative approaches through
scenario modeling and experimentation, monitoring, and adaptive management also can improve contingency planning (Butterworth
and Punt 1999).
5. Use spatial organizing frameworks such as zoning for coordinating multiple management sectors and approaches in EBM.
Marine EBM will require multiple approaches to managing competing uses and authorities in the ocean, such as fisheries, recreation,
research, conservation, and shipping. Such activities can be coordinated spatially and temporally through ocean zoning or other spatially
specific management approaches (NMFS 1999, POC 2003, USCOP 2004, Young et al. 2007).
6. Link the governance structure with the scale of the ecosystem elements to be managed under an EBM approach.
Management decisions that are matched to the spatial scale of the ecosystem, to the programs for monitoring all desired ecosystem
attributes, and to the relevant management authorities are likely to be more successful in achieving ecosystem objectives (Sissenwine
and Mace 2003, Rosenberg and McLeod 2005, USGAO 2005). Coordination and decision feedbacks among the governing authorities
are a crucial part of successful EBM.
Figure 1. Simplified food-web diagram of the Southern Ocean (redrawn from CCAMLR’s Management of the
Antarctic, available at www.ccamlr.org/pu/E/e_pubs/am/man-ant/toc.htm).
56 BioScience • January 2008 / Vol. 58 No. 1
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importance of krill to predators, with the result that the recommended rates of removal are 25% lower than if predators
were not considered (CCAMLR 2006).
A second example of the ecosystem-based fishery approach is evident in the CCAMLR’s management of fisheries bycatch. Limits on the incidental mortality of nontarget
species have been established, and once these limits are met,
the target fishery can be closed, even if the quota for the target species has not been harvested. The CCAMLR’s approach
to EBM is iterative, taking into account new information as
it becomes available. However, the character of this environment makes data collection and fisheries observation expensive and logistically challenging. If ecosystem metrics
were adopted and monitored, information that is missing for
specific species would not necessarily mean that they would
be removed from management focus. In this way, food-web
and ecosystem metrics could themselves become the targets
of management (in addition to single-species metrics), and
consequently help drive management decisions and feedbacks.
High-latitude environments such as the Southern Ocean
may be especially susceptible to the impacts of multiple stressors such as those associated with climate change and with
multiple commercial fisheries (e.g., Atkinson et al. 2004).
Consequently, the effectiveness of the ecosystem approach currently is limited by insufficient data to understand the biological effects of fishery regulations on food-web elements,
potential lack of compliance with fishery regulations, and unknown effects of interactions of fishery management approaches with environmental change. For example, there is
no clear mechanism for linking the CCAMLR’s management
recommendations regarding catch limits with those developed
to manage the seal and whale fisheries. If management objectives, indicators, and strategies for diverse sectors were
better coordinated, potential trade-offs would likely become
more apparent. Because of the remote and large geographic
area covered by the CCAMLR, a mix of regulatory and
incentive-based approaches is likely to increase the chances
that ecosystem goals will be achievable.
Finally, the strength of the CCAMLR is in the organization
and scope of scientific research underpinning EBM for the
Southern Ocean. What is missing is a rigorous link between
the scientific recommendations emerging from this process
and policies that explicitly incorporate risk management in
setting acceptable catch limits for the species harvested in the
Southern Ocean. Tighter linkages between governance decisions and scientific information will increase the likelihood
of achieving overall ecosystem objectives.
The Bering Sea–Aleutian Islands ecosystem
The fisheries within the Bering Sea–Aleutian Islands (BSAI)
ecosystem are managed under a sophisticated multispecies
framework that is based on extensive monitoring by both fishers and managers. Similar to the management approach under the CCAMLR, the approach in the BSAI ecosystem can
be characterized as an ecosystem-based fishery management
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approach that is evolving to incorporate broader ecosystem
management elements more fully (box 2). Groundfish fisheries in the BSAI ecosystem are among the largest fisheries in
the world. They serve as an illustration for the way in which
conservative single-species management of multiple species
can contribute to an ecosystem approach to fisheries management. About 80 stocks of groundfish are recognized and
managed in the BSAI ecosystem (NPFMC 2006); chief among
these are stocks of walleye pollock, Pacific cod, and Atka
mackerel (box 3). Despite intensive commercial fishing, none
of the groundfish stocks is currently overfished according to
the technical definition under the regulations (Lauth 2007).
Removal levels and biomass of the primary commercial target species, walleye pollock, have been stable for more than
two decades, and the average trophic level of the catch (an indicator of sustainable fishing practices) has been stable for at
least 15 years (Boldt 2006), which represents approximately
one generation for most species involved.
In the BSAI groundfish fisheries, single-species management
is implemented by establishing annual or seasonal fishing quotas that are lower than the estimated maximum sustainable
yield, which is considered an upper limit on fishing effort
rather than a target. Quotas become more conservative as uncertainty about the status of the stock increases. Removals are
further restricted by limitations on the total catch of all
groundfish species combined. This combined quota is lower
than the sum of the individual quotas, thereby providing an
extra measure of precaution in management of this system.
Additional limits are established for the incidental catch of
nontarget and protected species; once these limits are reached,
the fishery is closed, even if catch quotas of target species have
not been reached. It is common in the BSAI groundfish fisheries for caps on the mortality of protected species to limit fishing on target species in a given area and season (NPFMC
2006).
The simultaneous application of quotas at the level of individual stock, combined total catch, incidental take of nontarget species, and incidental take of protected species
substantially reduces the likelihood of long-term impairment of the ecosystem by fishing. Setting such quotas requires
an extensive data collection and management system. Data
collection includes fishery-independent survey data (i.e.,
both bottom trawl and acoustic surveys for groundfish and
surface trawls for forage fish) that supplement the fisherydependent data provided by the fishers and observers on
commercial fishery vessels (e.g., catch per unit effort, biological
samples, bycatch monitoring, etc.). The annual cost of the
fishery-independent data currently is on the order of $20
million to $30 million a year, an investment that has been
acceptable to the federal government and the fishing industry, given the approximately $1 billion annual value of the
fishery (NPFMC 2006).
Other fishery management methods are applied in the
BSAI groundfish fisheries to account for some predator-prey
interactions and habitat protection (NMFS 2003, NPFMC
2006). Large areas have been closed to fishing, depending on
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Box 2. Summary of current and potential ecosystem-based management strategies
for selected marine and coastal management areas.
Antarctic/Southern Ocean
Current strategies: Spatial boundaries are defined by international agreement through the Commission for the Conservation of
Antarctic Marine Living Resources. Clear statements of objectives are defined for fisheries, but not for marine mammals and for only
some birds. Human activities (commercial fisheries) are explicitly considered. A zoning framework is applied (as a sectoral framework).
The governance structure allows for the ecosystem-based management (EBM) approach, but monitoring and enforcement are difficult.
Additional components for a comprehensive EBM approach: Develop indicators of ecosystem status and function (current
management relies on the status and trends in some individual species). Diversify approaches and tools to hedge against uncertainty in
food-web dynamics, future climate, and so on. Develop spatial strategies for each sector at smaller, ecologically relevant scales using a
mix of regulatory and incentive-based approaches. Link the governance structure fully to scientific processes and adaptive management.
Bering Sea/Aleutian Islands
Current strategies: Spatial boundaries are defined as large marine ecosystems on the basis on hydrographic, bathymetric, and
biogeographic criteria. Fishery-based management objectives are based on allowable catch for targeted and nontargeted species caught
as bycatch. Indicators for fished part of food web and some habitats are well monitored. Quotas for nontarget species reduce risk for the
overall food web, some food-web experiments are being conducted, and uncertainty is explicitly included in stock assessments for
pollock, a primary fished species. Spatially explicit fishery regulations are used. Governance is relatively simple because few management
sectors are relevant (i.e., federal and state governments, the fishing community).
Additional components for a comprehensive EBM approach: Identify ecologically and politically relevant subregions of the ecosystem
for more targeted management. Adopt broader ecosystem objectives, taking into account socially valued habitats and species in higher
and lower trophic levels. Include indicators for larger marine mammals, climate-mediated processes for better predictions of ecosystem
responses to management. Incorporate future scenarios of climate change into fishery and habitat management strategies to increase the
certainty of ecosystem response. Broaden governance to include other managed parts of the ecosystem (e.g., marine mammals,
watershed influences).
Great Barrier Reef Marine Park
Current strategies: The boundary of the managed area is defined by the extent of the Great Barrier Reef (GBR) and adjacent waters.
The objectives adopted by a broad group of users explicitly include ecological sustainability, through protection of natural resources and
human use and enjoyment of the Great Barrier Reef. There is monitoring of biophysical and some socioeconomic attributes of the GBR
Marine Park and no single report card for reef “health.” A 25-year strategic plan outlines eight broad strategy areas; education of the
public is key. Clear zoning maps specify the uses of the GBR Marine Park (e.g., commercial uses, tourism, recreation, traditional uses,
research) and the degree of protection (“general use” or “preservation,” e.g.). The GBR Marine Park Authority has an explicitly stated
relationship with Commonwealth and Queensland governmental organizations, roles are spelled out in governance documents, and
Australia’s 1998 oceans policy provides a framework for EBM in marine waters.
Additional components for a comprehensive EBM approach: Advance work on performance indicators and identify clear paths for
monitoring feedback into strategies. Emphasize social and economic aspects of research and adaptive management, in addition to the
biophysical aspect. Develop a plan for dealing with external factors affecting the quality of resources within the GBR Marine Park, such
as water quality, climate change, coastal development, and fisheries. Education about the 2004 zoning plan, and enforcement of it, are
critical. Improve coordination between commonwealth and state laws in managing the GBR Marine Park.
California coast
Current strategies: Spatial boundaries are defined by state statute. The marine protected area and general coastal ocean management
objectives are stated. Human activities (e.g., commercial fisheries) are explicitly considered. A zoning framework is applied (within the
context of marine protected area networks).
Additional components for a comprehensive EBM approach: Adopt specific objectives for multiple natural and human ecosystem
components. Identify a set of natural and human system indicators for tracking progress. Identify and get commitments for the role of
different management sectors in contributing to ecosystem objectives. Link the governance structure to management and scientific
processes.
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gear type and season, for the protection of habitat and important prey species. For example, areas around Steller sea lion
rookeries are closed to some types of fishing when pups are
present, in order to preserve the prey items required for pup
survival and growth. Experiments to determine how fishing
levels affect the prey field for Steller sea lions are testing these
impacts explicitly (Wilson et al. 2003).
In 2006, the Regional Fishery Management Council responsible for developing recommendations to the federal
government on acceptable catch levels created an ecosystem
committee for the purpose of developing a fishery ecosystem
plan for the Aleutian Islands region. This ecosystem plan
will be an overarching guide for the implementation of EBM
of fisheries in this area, which is a subregion of the BSAI
ecosystem. This work is considered a pilot effort and its
effectiveness will be evaluated as it is implemented. Whether
other subregions of the BSAI ecosystem should be managed
more precisely will depend in part on the distinctness of
ecosystem responses in different parts of the system. For example, Ciannelli and colleagues (2004) used food-web energetic models and information on species’ dispersal distances
to define the spatial scales over which there are predator and
prey feedbacks for some of the species in the Pribilof Islands
portion of the BSAI ecosystem.
Although parts of the BSAI ecosystem are subject to an
ecosystem-based fishery approach, unknown effects of other
factors within the ecosystem reduce the certainty of predicting future states. Some drivers in the system are poorly studied, such as food-web interactions and relationships between
habitat quality and productivity of target and nontarget
species. For example, the implications of potential food-web
interactions among whales, pinnipeds, sea otters, urchins,
and kelp forests (Springer et al. 2003, DeMaster et al. 2006)
for fishery management are not well understood. In addition,
the impacts on the ecosystem of rising water temperatures,
loss of sea ice, and changes in pH and carbonate saturation
are just beginning to be examined. A five-year, $30-million
research program, which will begin in 2008, is designed to
provide an initial understanding of some of these key processes
and interactions associated with increasing concentrations of
greenhouse gases.
An improved understanding of all elements of the ecosystem within a management strategy evaluation framework
(e.g., Butterworth and Punt 1999) will better allow commercial and subsistence hunters and fishers in the region to
prepare for likely changes in the Bering Sea over the next 20
to 50 years. Including management objectives for a broader
scope of species or habitat types within the ecosystem will require the difficult work of engaging representatives from
more sectors (e.g., Alaska native subsistence whaling interests).
The relatively low density of the human population in the
BSAI ecosystem makes such governance challenges relatively
minor, compared with systems such as California’s coast,
where many more stakeholders are involved.
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Box 3. Types of species in the fishery
management plan for the Bering Sea–Aleutian
Island ecosystem.
Prohibited species
Prohibited species are those species and species groups that
when caught must be returned to the sea with a minimum
of injury, except when their retention is authorized by other
applicable law. Foreign fisheries must maintain catch
records for each of these species. All bycatch of marine
mammals must be reported to the appropriate agency.
Examples of prohibited species include Pacific halibut,
Pacific herring, salmonids, king crab, and tanner crab.
Target species
Target species are commercially important and generally
targeted upon by the groundfish fishery. Sufficient data
exist to specify total allowable catch (TAC) and to manage
each species or species group separately. Catch records must
be kept for each of these species. Target species, or species
groups, may be combined or split by regulatory
amendment. Examples of target species defined in the
regulations include atka mackerel, arrowtooth flounder,
flathead sole, Greenland turbot, Pacific cod, Pacific Ocean
perch, rock sole, sablefish, squid, walleye pollock, and
yellowfin sole.
Other species
Other species have little economic value and are not usually
targeted, but they may be significant components of the
ecosystem or have economic potential. A single TAC applies
to this category as a whole. Catch records must be kept for
each of these species. Other species include sculpin,
eulachon, capelin, shark, skates, smelt, and octopus.
Nonspecified species
Nonspecified species are those species and species groups of
no current economic value taken as incidental catch in the
target fisheries. Virtually no data exist that would allow
population assessments. No record of catch is necessary. No
TAC is established for this category; the allowable catch is
the amount that is taken incidentally during fishing for
target and other species, whether retained or discarded.
Nonspecified species include numerous fish and
invertebrates such as grenadiers, eelpouts, sea urchins,
and mussels.
The Great Barrier Reef Marine Park, Australia
The Great Barrier Reef (GBR) ecosystem boasts a system-wide
spatial management approach that is arguably the world’s most
sophisticated and extensively implemented example of
marine zoning. Stretching more than 2300 kilometers along
the northeastern coast of Australia and comprising 70 bioregions, the GBR is the largest and most famous reef system
January 2008 / Vol. 58 No. 1 • BioScience 59
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however, other threats were recognized, and
comprehensive management of this reef system has now evolved to the point where multiple uses and protection of marine biodiversity
are addressed directly. The GBRMPA management philosophy explicitly emphasizes management at the ecosystem level, conservation
and reasonable use, public participation and
community involvement, and monitoring and
performance evaluation.
Protection recently took an enormous step
forward with the establishment of a new zoning
plan on 1 July 2004. As a consequence, the proportion of no-take zones increased from less
than 5% to more than 33% of the total area of
the park (figure 2). These no-take zones protect
representative examples of each of the broad
habitat types in the GBR and represent the
world’s largest such network in operation today.
Although increasing the protection of biodiversity was a top priority, a further aim was to
minimize impacts on the existing users of the
GBR Marine Park, including commercial and
recreational fishers. Both these aims were
achieved by a comprehensive program of both
scientific input and community involvement; the
participatory planning was the largest such exercise for any environmental issue in Australia’s
history. The rationales for the decisions made are
summarized in a series of biophysical operational principles and in a set of social, economic,
cultural, and management feasibility operational principles (Fernandes et al. 2005). Managing for resilience is explicitly mentioned in
GBRMPA documents.
There is also a clear awareness that no-take
areas in isolation cannot achieve all conservation
aims, and management of land use is therefore
Figure 2. Green zones (no-take areas) in the Great Barrier Reef before and
considered a critical component of successful reef
after enactment of the 2004 zoning plan.
management. This is facilitated by legislation that
in the world and the largest World Heritage Area. Coral reefs
allows regulation of activities outside the GBR that could
in general are both the most diverse of all marine ecosystems
have adverse impacts (Day 2002) and by prioritizing marine
and among the most threatened (Pandolfi et al. 2003). Threats
areas that lie adjacent to protected land (Fernandes et al.
include not only the loss of intensively harvested species (in2005); the Reef Water Quality Protection Plan of 2003 is an
cluding elimination through fishing of spawning aggregation
example of this approach. Global temperature rise and acidsites) but also the loss of the coral reef framework itself
ification cannot, of course, be managed directly on a local scale,
because of destructive fishing practices, coral disease, coral
but some evidence exists that reducing local impacts imbleaching, algal overgrowth, and now ocean acidification.
proves reef resilience to global stressors (Hughes et al. 2007).
Although the GBR often is assumed to be in relatively
Thus, although the ecosystem outcomes remain to be docugood condition, recent analyses indicate that it too has sufmented, the GBRMPA is arguably the best example we have
fered substantial degradation (Pandolfi et al. 2003, Bellwood
of EBM in place today.
et al. 2004). Fortunately, the GBR has the benefit of being
A thorough review of the management of the GBR Marine
almost entirely within the jurisdiction of the Great Barrier Reef
Park was completed in 2006 (DEH 2006), and the recomMarine Park Authority (GBRMPA; www.gbrmpa.gov.au/) of
mendations include a sophisticated list of the next issues to
Australia. The GBRMPA was established in 1975, and concerns
address. Relatively speaking, the management of the GBR area
about oil drilling drove its early development. Over the years,
is mature enough that detailed implementation of many
60 BioScience • January 2008 / Vol. 58 No. 1
www.biosciencemag.org
Articles
EBM principles already is under way. The review highlighted
the need for greater attention to social and economic issues
in research, reporting, and governance, and pointed out that
relatively more attention has been focused on understanding
and managing the biophysical aspects of the ecosystem. For
example, there has been no assessment of cumulative regional, social, and economic impacts of the 2004 zoning plan
on the viability of businesses. Management of the park’s resources also would benefit from careful consideration of external factors affecting the status of the ecosystem—such as
impacts from climate change, land-based inputs of sediments and nutrients from development, and the way in which
fishery management on highly migratory species affects the
ecosystem’s functioning. Finally, better coordination among
many state and commonwealth laws (e.g., there are six laws
regulating fisheries alone) will help to protect the environmental and cultural values that are part of the GBRMPA’s
ecosystem objectives.
Ecosystem-based management
approaches in coastal California
California is a leader in promoting marine EBM approaches
through legislation. California’s Marine Life Management
Act (MLMA) became law in early 1999, and it represents an
ecosystem-based approach to managing all marine wildlife in
the state’s waters (CDFG 2007). The goals of the MLMA include conservation of nonconsumptive values of marine resources, sustainability of fisheries and reduction in bycatch,
habitat conservation and restoration, and consideration of
socioeconomic benefits to fishing communities from changes
in management of marine resources. The fishery management
plans included under the law’s umbrella must be linked in a
master plan, which defines the ecosystem-based management principles, prioritizes fisheries for plan development, and
incorporates interactions among management plans for individual fisheries. The 29 species included in the prioritized
list are diverse taxonomically, including surfperches, sharks
and rays, sea basses, halibut, sea urchins, lobster, sea cucumbers, subtidal snails, intertidal invertebrates, and two species
of kelp.
One of the key fishery management plans for California is
the nearshore fishery management plan, which must contain
fishery management objectives for 19 species of finfish while
also meeting the ecosystem and nonconsumptive use provisions of the MLMA. A unique feature of the nearshore fishery management plan is its inclusion of an adaptive
management framework for setting biological objectives that
explicitly adjusts for the quality of information over time
(Kaufman et al. 2004). A so-called control rule in the plan
guides the establishment of total catch limits for each species,
and the rule is designed to evolve over time as data availability
increases on the ecosystem effects of harvest. The design of
the control rule encourages data collection and analysis as the
EBM approaches to setting harvest levels are implemented,
and acknowledges that such approaches are likely to be
experimental in the early stages. As more information is
www.biosciencemag.org
gathered over time, the precautionary approach to setting harvest limits can be moderated and replaced by more informed
catch limits that incorporate knowledge of ecosystem relationships and interactions among species.
The MLMA also requires that a plan for a network of
marine protected areas be developed as a means to achieve the
objectives of the act. The Marine Life Protection Act Initiative is designed to use scientific, policy, and public input to
identify networks of MPAs along the California coast. After
a thorough two-year science-stakeholder-policy process, the
first of the regional networks—along the central coast—was
approved in April 2007 by the California Fish and Game
Commission (CDFG 2007). The science-policy process will
begin anew for adopting an MPA network along the northcentral California coastal region. Previous to the MLMA enactment, a network of marine reserves in the Channel Islands
in southern California waters was developing, and after a
rigorous science-policy process to identify scenarios of protected areas, the network currently contains 453 square kilometers of state-managed reserves within the existing federal
Channel Islands National Marine Sanctuary (Airame et al.
2003; www.dfg.ca.gov/mrd/channel_islands/index.html).
More recently, the California state legislature passed the
California Ocean Protection Act, which creates a state Ocean
Protection Council (OPC) composed of the state agencies that
have responsibility for ocean issues. The California Ocean Protection Act also establishes a $10 million Ocean Protection
Trust Fund, which is designed to reduce threats to marine
ecosystems through incentives for sustainable fisheries, improved management, and monitoring. As part of implementing the new act, the OPC created a five-year strategic plan
that identifies goals for the California marine ecosystem and
outlines measurable outcomes and key actions for achieving
these goals (COPC 2006). The goals laid out in the plan discuss explicitly that an EBM approach is needed to maintain
ocean and coastal ecosystems, including coordinating governing bodies; learning about the system through monitoring and research; maintaining water quality, physical processes,
habitat structure, and wildlife; and conducting education
and outreach.
A more comprehensive EBM approach in California’s
coastal region, at the scale of the entire California coast,
could be achieved through application of many of the EBM
principles that already have been implemented at local scales
for more focused issues (e.g., Channel Islands and Central
Coast MPA network processes). In particular, using public participatory processes to adopt specific objectives for multiple
natural and human ecosystem components for coastal California would help greatly in coordinating ongoing and
future work across many sectors. Such work could guide
actions affecting the ecosystem beyond establishing MPA
networks or setting fishery catch limits, such as land- and
water-use regulations, shipping practices, and oil and gas
development. Once the ecosystem objectives are broadly
agreed upon, different management sectors can identify acJanuary 2008 / Vol. 58 No. 1 • BioScience 61
Articles
tions (and expected ecosystem responses) to which they will
contribute under an accountability system.
Conclusions
The case examples we highlight in this article illustrate the
current, relatively young state of marine EBM in practice. Evaluating the success of something as complex as EBM will take
diligent monitoring and evaluation of strategies and desired
ecosystem components—such data are just beginning to
emerge. In the meantime, strategies in each case are evolving
as managers slowly expand the components of the ecosystem
included within their evaluations and the EBM principles they
include in management approaches. The examples we highlight differ in the particular aspects of EBM that have been
applied, yet each suggests several promising next steps that
could advance EBM approaches and improve ecosystem
prospects.
Fishery-based ecosystem management approaches in the
Antarctic and BSAI ecosystems provide good examples of how
explicit adoption of objectives and monitoring of indicators
can drive management decisions through governance bodies
charged with meeting those objectives. The multispecies fisheries objectives in those two regions are mostly being met
through evolving management approaches, but components
of those ecosystems that are peripheral to the managed portions are not getting the same level of attention as target
species. More work to expand ecosystem objectives and management sectors beyond fishing interests could bolster fisheries and support broader ecosystem functions, such as
persistence of migratory marine mammals, sea birds, and
habitats, in both of these regions. Both of these ecosystembased fishery management examples also would benefit from
broadening their strategies to include a combination of regulatory and socioeconomic incentives as a way to meet more
comprehensive ecosystem objectives.
The GBRMPA is the current gold standard for EBM in the
oceans, and its success thus far in applying EBM principles is
in large part because of its equal attention to both the human
and natural systems parts of ecosystem management.
Tracing the evolution of management of the GBR from one
largely driven by concerns about oil extraction to one guided
by full ecosystem objectives and management of multiple
threats is instructive for the younger regional EBM
efforts. Managers in the GBRMPA clearly recognize the
potentially significant ecosystem benefits that arise from
involving stakeholders in identifying and adopting strategies to achieve ecosystem goals. The ecosystem work through
the GBRMPA benefits from clearly identified entry points for
all elements (natural, social, political) of the decision framework. How such an approach ultimately will succeed in
achieving the biodiversity and socioeconomic objectives to
which they aspire will become clearer over time.
Finally, the sort of adaptive approach adopted in California, which will require many years for ecosystem-dynamic
properties to emerge, will very likely be fruitful in most
approaches to EBM. EBM is in the early stages of imple62 BioScience • January 2008 / Vol. 58 No. 1
mentation and evaluation. Debate about how best to implement EBM in the ocean will be informed by tests designed to
guide the establishment and monitoring of scientifically
based thresholds, to determine the impact of decisions triggered when such thresholds are reached, and to elucidate
decision implementation and feedback mechanisms within
specific governance structures. Such first steps will improve
our ability to identify opportunities for new and coordinated
actions that have the greatest likelihood of improving ecosystem function. These steps recognize that EBM per se is
not our objective, and instead place the emphasis where it
belongs—on improving ecosystem resilience and function.
Acknowledgments
We thank Heather Leslie, Mike Ford, Jeff Hard, Phil Levin, Rick
Methot, Enric Sala, and Steve Palumbi and his lab group for
comments on an earlier version of this manuscript. Comments
from three anonymous reviewers greatly improved the practical nature of the messages in this article. Kimberly Toal and
Jeremy Davies improved the figures. Discussions with Andy
Rosenberg and Will Stelle at the “Managing for Resilience:
An Integrated Approach to Coastal Marine Science and Conservation” symposium at the University of Washington’s
Friday Harbor Laboratories helped us better understand the
challenges and opportunities associated with implementing
EBM in the oceans. We also thank the director and staff of
Friday Harbor Laboratories, the David and Lucile Packard
Foundation, and the Andrew W. Mellon Foundation for supporting the symposium, its diverse participants, and stimulating discussion of the ideas contained in this manuscript.
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