Ecosystem-Based Management for the Oceansby Karen McLeod
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Conventional management approaches cannot meet the challenges faced by ocean and coastal ecosystems today. Consequently, national and international bodies have called for a shift toward more comprehensive ecosystem-based marine management. Synthesizing a vast amount of current knowledge, Ecosystem-Based Management for the Oceans is a comprehensive guide to utilizing this promising new approach.
At its core, ecosystem-based management (EBM) is about acknowledging connections. Instead of focusing on the impacts of single activities on the delivery of individual ecosystem services, EBM focuses on the array of services that we receive from marine systems, the interactive and cumulative effects of multiple human activities on these coupled ecological and social systems, and the importance of working towards common goals across sectors. Ecosystem-Based Management for the Oceans provides a conceptual framework for students and professionals who want to understand and utilize this powerful approach. And it employs case studies that draw on the experiences of EBM practitioners to demonstrate how EBM principles can be applied to real-world problems.
The book emphasizes the importance of understanding the factors that contribute to social and ecological resilience —the extent to which a system can maintain its structure, function, and identity in the face of disturbance. Utilizing the resilience framework, professionals can better predict how systems will respond to a variety of disturbances, as well as to a range of management alternatives. Ecosystem-Based Management for the Oceans presents the latest science of resilience, while it provides tools for the design and implementation of responsive EBM solutions.
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Ecosystem-Based Management for the Oceans
By Karen McLeod, Heather Leslie
ISLAND PRESSCopyright © 2009 Island Press
All rights reserved.
Why Ecosystem-Based Management?
Karen L. McLeod and Heather M. Leslie
As illustrated by the preceding stories of ice bears and Puget Sound, ocean and coastal ecosystems around the globe are in trouble. Both the severity and scale of impacts to these systems—including those from climate change, biodiversity loss, overfishing, pollution, coastal development, habitat loss, and fragmentation—are increasing (MA 2005a, b), with no corner of the globe untouched (Halpern et al. 2008a). Acting in concert, these impacts decrease the ability of marine ecosystems to deliver vital ecosystem services to humankind, such as abundant seafood, clean water, renewable energy, and the protection of coastal areas from storm damage.
The unprecedented environmental challenges facing the oceans require us as scientists, practitioners, and citizens to embrace a broader vision than ever before of what we want to achieve through coastal and ocean management (UNEP 2006). This vision must encompass not only the long-term health of coasts and oceans, but also human well-being. Sustaining the long-term capacity of systems to deliver ecosystem services is the core goal of ecosystem-based management (EBM) for the oceans (Rosenberg and McLeod 2005). Moving forward with EBM requires synthesizing and applying knowledge from across the social and natural sciences as well as the humanities (Leslie and McLeod 2007) and raises numerous questions:
How can we better account for the interactive and cumulative effects of the growing number of human activities affecting marine ecosystems?
How well do we understand feedbacks between the social and ecological components of systems, and what are the broader implications of these linkages?
In an increasingly dynamic world, how can management institutions respond more rapidly to changing, and often surprising, conditions?
How can small-scale management decisions make a difference in light of large-scale change (especially climate change)?
How can we better recognize that systems are approaching critical thresholds? In other words, how do we know how likely they are to shift to a fundamentally different state (e.g., from coral to algal dominance on tropical reefs) that will produce a radically different set of services?
To what extent are these shifts reversible (especially over the scale of a human lifetime)? How can we identify and bolster attributes that decrease vulnerability to such shifts?
We tackle these and related questions in this book through synthesis of the science, policy, and practice of ecosystem-based management.
What Is Ecosystem-Based Management for the Oceans?
EBM is a new approach to managing the range of human activities that affect marine ecosystems, as called for by numerous national and international bodies (WSSD 2002; POC 2003; USCOP 2004). In 2005, more than two hundred academic scientists and policy experts from US institutions agreed by consensus on the following definition of EBM for the oceans: "Ecosystem-based management is an integrated approach to management that considers the entire ecosystem, including humans. The goal of ecosystem-based management is to maintain an ecosystem in a healthy, productive and resilient condition so that it can provide the services humans want and need. Ecosystem- based management differs from current approaches that usually focus on a single species, sector, activity or concern; it considers the cumulative impacts of different sectors" (McLeod et al. 2005). The following key elements are based on that definition:
1. Connections At its core, EBM is about acknowledging connections (Guerry 2005; Leslie and McLeod 2007), including first and foremost, the inextricable linkages between marine ecosystems and social systems. Human well-being is intimately connected to ecosystems through the delivery of ecosystem services across a range of scales. Cultures, economies, and institutions form and evolve in response to their local or regional ecosystem contexts. Human behavior, including the extent, intensity, and type of activity, affects natural systems. Humans interact with coasts and oceans as individuals (consumers, surfers, or fishers), as organizations (local fish markets or canneries), and as institutions (trade organizations, fishery management councils, or conservation organizations), each within a particular cultural context. These dynamic, linked systems of humans and nature are called "coupled social–ecological systems" (fig. 1.1).
EBM is fundamentally a place-based approach, and coupled systems occur across a range of spatial scales from a local ecosystem, such as an individual estuary, to an entire large marine ecosystem, such as the California Current off the US west coast. Thus, there is no single "correct" scale at which to do EBM. Instead, it is an approach to be implemented over a range of scales, acknowledging the connections and leaky boundaries among scales.
2. Cumulative impacts EBM focuses on how individual actions affect the ecosystem services that flow from these coupled systems. In other words, what are the cumulative impacts of multiple activities, both within and among sectors, on the delivery of ecosystem services? Accounting for cumulative impacts also involves recognition of interactions with drivers of change that operate over smaller or larger scales than the scale of management (see Guichard and Peterson, chap. 5 of this volume, for more on cross-scale interactions). Inevitably, a comprehensive accounting of cumulative impacts requires that sectors ultimately work toward a common goal (as expanded upon by Rosenberg and Sandifer in chap. 2 of this volume).
3. Multiple objectives EBM focuses on the range of benefits that we receive from marine systems, rather than single ecosystem services. In a particular place, people want and expect to receive multiple services, which may include vibrant commercial and recreational fisheries, biodiversity conservation, renewable energy from wind or waves, coastal protection, diving, and sea kayaking. In order to fully implement EBM, we need to understand the connections among these services and the suite of factors affecting their production and delivery. This will allow us to make informed choices about trade-offs among the multiple objectives that are fundamental to a more comprehensive approach. Being explicit about trade-offs among multiple objectives (which often correspond to services) is a critical component of EBM. Importantly, decisions about trade-offs among services or sectors certainly occur under current management, but they are most often made implicitly, rather than explicitly (see Rosenberg and Sandifer, chap. 2 of this volume, for a detailed treatment of this topic).
Finally, it is important to note that the concept of ecosystem-based management is grounded in the idea that ultimately we are managing people's influences on ecosystems, not ecosystems themselves. Thus, this volume brings together knowledge of scientists, managers, and practitioners to advance ecosystem-based management of the human activities that affect these systems, rather than ecosystem management, which implies that we are managing systems, rather than people.
Conservation of Ecosystem Services
Although elements of an EBM approach have been applied for decades both on land and in the sea, what is innovative about the current EBM movement is its focus on conservation of the long-term potential of systems to sustain the delivery of a broad suite of ecosystem services (McLeod et al. 2005; Rosenberg and McLeod 2005). Thus, each sector of human activity (fisheries, coastal development, tourism, etc.) must consider how it affects ecosystem structure, functioning, and key processes, and all sectors must collectively work toward the common goal of maintaining these components of ecosystem health. This sharply contrasts with current management practices that tend to focus on the short-term provision of single services and under which individual sectors are often working at cross-purposes (POC 2003; USCOP 2004).
The Millennium Ecosystem Assessment assessed the status of the world's ecosystems, the services they produce, and how changes in the global environment are affecting human well-being, concluding that 60% of ecosystem services globally are degraded (MA 2005b). Supporting services, or the fundamental ecological processes that sustain ecosystem functioning (e.g., nutrient cycling and photosynthesis), underlie all other services that are directly used by people. Remaining services are categorized as (1) provisioning services, such as food or fiber; (2) regulating services, such as climate regulation or coastal protection; or (3) cultural services, or the nonmaterial benefits that are important to our well-being (table 1.1). Individual services may fall into multiple categories; the specific labels that we attach to them are less important than acknowledging the breadth of services that affect our well-being. In particular, we have historically focused management on maintaining the flow of provisioning services, to the detriment of regulating, cultural, and supporting services.
Importantly, the focus on ecosystem services, rather than ecosystem functioning per se, explicitly acknowledges social–ecological connections (see fig. 1.1). Specifically, it requires accounting for the social, ecological, and physical factors affecting the production of services, as well as those that affect their delivery. For example, the provision of local, healthy, wild salmon for food depends upon (1) salmonid populations that are robust to fishing pressure; (2) suitable habitat; (3) other ecosystem components such as availability of prey or nursery habitat; (4) water quality; (5) local fleet access, including harbors; and (6) local markets and restaurants (Halpern et al. 2008b).
The ecosystem service focus is not without its limitations, and it raises key moral and ethical questions. For one, this perspective is fundamentally anthropocentric, reflecting human values and experience. In many ways this is appropriate, given that EBM is focused on managing human behavior. Intrinsic values of ecosystems ("existence values") are captured as cultural services to humans, although these are arguably the most challenging to value from an economic perspective (see Wainger and Boyd, chap. 6 of this volume). Ultimately, the ecosystem services perspective privileges human well-being over the well-being of other species, which is at odds with an ecological worldview that does not grant special status to humans. Thus, the evolution of management practices may call for a coevolution of ethics, as discussed in detail by Moore and Russell (chap. 18 of this volume).
Building on the Legacy of EBM on Land
Management of human activities that influence coastal and marine ecosystems lags behind management of terrestrial areas for several reasons. First, our awareness and knowledge of the terrestrial realm is greater than that of the sea—it is our home, and consequently, more scientific and technical resources have been devoted to understanding the dynamics and drivers of change to terrestrial ecosystems as compared with marine systems. Moreover, the watery medium that dominates coastal and ocean ecosystems creates technical challenges to understanding ecosystem dynamics and how these dynamics influence the provision of ecosystem services. Finally, the institutions governing allocation and use of marine resources are quite different from those governing terrestrial resources; private property is much less common in the sea, and common pool or open access institutions are more the norm. For all of these reasons, we need to think about managing marine systems differently from their terrestrial counterparts. This means building on the experience of managers and conservation practitioners on land but not necessarily trying to duplicate their approaches or aims.
That being said, decades of ecosystem-based approaches to land conservation and management (particularly in forests) provide some critical insights regarding the challenges and opportunities of marine EBM. Many, if not most, of the 428,000 km2 of publicly held lands in the United States (almost 1/3 of the US land area) are managed for multiple objectives, including timber harvest, consumptive and nonconsumptive recreation, energy development, and wildlife conservation. Scientists and practitioners face a similar set of challenges in the sea, which requires considering the cumulative and potentially synergistic impacts of multiple activities, and developing ways to effectively communicate and integrate this information in a policy environment. Many regulatory tools developed to aid terrestrial ecosystem-based approaches (e.g., zoning and protected areas, market-based incentives) also apply to coastal and marine systems. Moreover, the legal mechanisms that guide land management decisions, such as the National Environmental Policy Act and the Endangered Species Act, are often invoked in marine settings as well (see Searles Jones and Ganey, chap. 10 of this volume, for further discussion).
Resilience Science as a Conceptual Backbone for EBM
Another key feature of EBM is the ability to embrace change, both in the increasingly dynamic world around us and in ourselves. The world's people are more connected than ever before; the flow of information, commerce, and people themselves is unprecedented. These connections bring opportunities as well as challenges. Embracing change requires us to better understand what influences the responses of systems, both human and natural, to a range of disturbances. Will a system resist disturbance, rebound quickly, slowly degrade, or shift to a completely new state? Once a threshold is crossed, is it possible for a system to return to a preexisting state; in other words, is the change reversible? Thus, understanding resilience—the extent to which a system can maintain its structure, function, and identity in the face of disturbance—can enable us to better predict how systems will respond not only to a growing array of perturbations, but also to a spectrum of management alternatives.
Importantly, resilience is not always a positive attribute. In other words, our aim will not always be to maintain or enhance the resilience of an existing state. As Boesch and Goldman (chap. 15 of this volume) describe, poor water quality, depleted fisheries, and the considerable inputs of nutrients and sediments from upland areas of the watershed characterize the current state of the Chesapeake Bay system, one that stakeholders from throughout the region are working to change. Restoration of sea grass beds, oyster reefs, and other bay habitats, and changes in farming, waste management, and development practices, are among the strategies being used to "erode" the resilience of the current state of the system and to help shift it to a more desirable one characterized by abundant fisheries, clean water, and vibrant habitats.
Key characteristics of resilience science include recognizing (1) the close coupling between social and ecological systems, (2) the existence of multiple possible states and abrupt changes among them, and (3) the contributions to system resilience of diversity and interactions across scales of space, time, and organization (Leslie and Kinzig, chap. 4 of this volume). A central contribution of resilience science to EBM is recognition that systems are constantly changing in ways that cannot be fully predicted or controlled. Consequently, an adaptive management framework is recommended (Anderies et al. 2006; Leslie and Kinzig, chap. 4 of this volume; Guichard and Peterson, chap. 5 of this volume). Learning to sustain and enhance the ability of systems to cope with uncertainty and surprise is in sharp contrast with conventional management approaches that tend to focus on maximizing production of particular services by reducing variability and controlling changes in systems that are assumed to be stable (e.g., maximum sustainable yield of fisheries; see Anderies et al. 2006 for further discussion). Resilience science also includes a strong multiscale perspective that emphasizes interactions and cooperation across scales, rather than centralization or decentralization (Adger et al. 2005; Kinzig et al. 2006). Such an approach is critical to the effective implementation of EBM, which requires both bottom-up and top-down approaches (see McLeod and Leslie, chap. 17 of this volume). As discussed above, there is no correct spatial scale at which EBM should be implemented. Thus, efforts that range from local-scale, community-based efforts like that in Port Orford, Oregon (Wedell et al. 2005), to national-level mandates such as Canada's Oceans Act (see Rosenberg et al., chap. 16 of this volume) are critical to advancing EBM. The challenge lies in determining how to create bridges for meaningful connections across scales. Despite increasing application of resilience frameworks to management in terrestrial and freshwater systems (Walker et al. 2006), the use of these concepts in the marine realm is in its infancy (but see Nyström et al. 2000; Hughes et al. 2003; Bellwood et al. 2004; Hughes et al. 2005).
Excerpted from Ecosystem-Based Management for the Oceans by Karen McLeod, Heather Leslie. Copyright © 2009 Island Press. Excerpted by permission of ISLAND PRESS.
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Meet the Author
Karen L. McLeod is the Director of Science for the Communication Partnership for Science and the Sea (COMPASS) at Oregon State University.
Heather M. Leslie is the Peggy and Henry D. Sharpe Assistant Professor of Environmental Studies and Biology at Brown University.
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