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Declining yields in many fisheries and the decay of treasured marine habitats such as coral reefs have heightened interest in establishing a comprehensive system of marine protected areas (MPAs) in the United States. MPAs, areas designated for special protection to enhance the management of marine resources, show promise as components of an ecosystem-based approach for conserving the ocean's living assets. However, MPA proposals often raise significant controversy, especially the provisions for marine reserves—zones within an MPA where removal or disturbance of resources is prohibited, sometimes referred to as closed or “no-take” areas. Some of the opposition to MPAs lies in resistance to “fencing the sea,” reflecting a long tradition of open access. This opposition continues despite compelling empirical evidence and strong theoretical arguments indicating the value of using reserves as a tool to improve fisheries management, to preserve habitat and biodiversity, and to enhance the esthetic and recreational value of marine areas. The controversy persists because we lack a scientific consensus on the optimal design and use of reserves and we have only limited experience in determining the costs and benefits relative to more conventional management approaches. The current decline in the health of the ocean's living resources, an indication of the inadequacy of conventional approaches, and the increasing level of threat have made it more urgent to evaluate how MPAs and reserves can be employed in the United States to solve some of the pressing problems in marine management.
RECOGNIZING THE LIMITS
The ocean inspires awe; its vast expanse of water spans most of the earth's surface and fills the deep basins between continents. From the surface, the ocean appears uniform and limitless, seemingly too immense to feel the impacts of human activities. These perceptions led to the philosophy expressed by Hugo Grotius, a Dutchman in the 1600s, that the seas could not be harmed by human deeds and therefore needed no protection. His thinking established the principle of “freedom of the seas,” a concept that continues to influence ocean policy despite clear evidence that human impacts such as overfishing, habitat destruction, drainage of wetlands, and pollution disrupt marine ecosystems and threaten the long-term productivity of the seas.
The flaw in the reasoning expressed by Grotius has been uncovered by research on the biology, chemistry, geology, and physics of the ocean. The sea is not a uniform, limitless expanse, but a patchwork of habitats and water masses occurring at scales that render them vulnerable to disturbance and depletion. The patchiness of the ocean is well known by fishers who do not cast their nets randomly but seek out areas where fish are abundant. There has been an increase in technology and fishing capacity that has led to a corresponding increase in the number of overfished stocks. Destruction of fish habitat as the result of dredging, wetland drainage, pollution, and ocean mining also contributes to the depletion of valuable marine species. As human populations continue to grow, so too does the pressure on all natural resources, making it not only more difficult, but also more critical to achieve sustainability in the use of living marine resources. These concerns have stimulated interest in and debate about the value and utility of approaches to marine resource management that provide more spatially defined methods for protecting vulnerable ocean habitats and conserving marine species, especially marine reserves and protected areas. Based on evidence from existing marine area closures in both temperate and tropical regions, marine reserves and protected areas will be effective tools for addressing conservation needs as part of integrated coastal and marine area management.
MANAGING MARINE RESOURCES
Management of living marine resources presents numerous challenges. The conventional approach typically involves management on a species-by-species basis with efforts focused on understanding population-level dynamics. For example, most fisheries target one or a few species; hence, managers and researchers have concentrated their efforts on understanding the population dynamics and effects of fishing on a species-by-species basis. Although this approach seems less complex, it does not resolve the difficulties of either managing multiple stocks or accurately assessing the status of marine species. This is compounded by the relative inaccessibility of many ocean habitats, the prohibi-
tive expense of comprehensive surveys, and the complex dynamics and spatial heterogeneity of marine ecosystems. In addition, the species-specific approach may fail to address changes that affect productivity throughout the ecosystem. These changes may include natural fluctuations in ocean conditions (such as water temperature), nutrient over-enrichment from agricultural run-off and other types of pollution, habitat loss from coastal development and destructive fishing practices, bycatch of non-target species, and changes in the composition of biological communities after removal of either a predator or a prey species.
In addition to challenges presented by nature, management challenges arise from social, economic, and institutional structures. Regulatory agencies are charged with the difficult but important task of balancing the needs of current users with those of future users of the resource as well as the long-term interests of the general public. Regulatory actions intended to maintain productivity often affect the livelihoods of the users and the stability of coastal communities, generating pressure to continue unsustainable levels of resource use to avoid short-term economic dislocation. Finally, responsibility for regulating activities in marine areas, extending from estuarine watersheds to the deep ocean, is fragmented among a daunting number of local, state, federal, and international entities. This complexity in jurisdictional responsibility often places a major barrier to developing coordinated policies for managing ocean resources across political boundaries. Although the protected area concept, with its emphasis on management of spaces rather than species, is not new and has been used frequently on land, until recently there have been less support and few interagency efforts to institute protected areas as a major marine management measure. MPA-based approaches will shift the focus from agency-specific problem management to interagency cooperation for implementing marine policies that recognize the spatial heterogeneity of marine habitats and the need to preserve the structure of marine ecosystems.
To address these issues, the National Oceanic and Atmospheric Administration (NOAA), National Park Service, and Fish and Wildlife Service requested that the National Research Council's Ocean Studies Board assemble a committee of experts to examine the utility of marine reserves and protected areas for conserving marine resources, including fisheries, habitat, and biological diversity. Although there are other, equally important goals, for MPAs, including recreation, tourism, education, and scientific inquiry, examination of these objectives was not part of this committee's specified statement of task and hence receives less emphasis in this report. The committee was directed to compare the benefits and costs of MPAs to more conventional management tools, explore the feasibility of implementation, and assess the scientific basis and adequacy of techniques for designing marine reserves and protected areas. This report presents the findings of the study and provides recommendations for the application of marine reserves and protected areas as a tool in marine area management.
CONCLUSIONS AND RECOMMENDATIONS
Effective implementation of marine reserves and protected areas depends on participation by the community of stakeholders in developing the management plan. Federal and state agencies will need to provide resources, expertise, and coordination to integrate individual MPAs into the frame-works for coastal and marine resource management in order to meet goals established at the state, regional, national, or international level. The lead agency will need to first identify all stakeholders, both on- and off-site, and then utilize methods of communication appropriate for various user groups. Additionally, the needs and concerns of affected communities must be evaluated and considered when choosing sites for marine reserves and protected areas. Stakeholders should be encouraged to participate in the process by employing their expertise as well as considering their concerns. Systematic social and economic studies will be required to recognize stakeholder groups, to assess the potential economic impacts of the MPA, and to determine community attitudes and goals.
The task of designing MPAs should follow four sequential steps: (1) evaluate conservation needs at both local and regional levels, (2) define the objectives and goals for establishing MPAs, (3) describe the key biological and oceanic features of the region, and (4) identify and choose site(s) that have the highest potential for implementation.
1. Conservation Needs. Local and regional conservation needs depend on the types of resources, the intensity and nature of human uses, and the physical and biological characteristics of the habitats. Consequently, the first step in planning an MPA is the identification and mapping of habitat types and living marine resources.
2. Objectives and Goals. The second step is the establishment of specific management goals for the proposed MPA. In most cases, the MPA will have multiple objectives such as protection of representative habitats, conservation of rare species, fish stock restoration or enhancement, or safeguarding of historical sites, among others. Ranking and prioritizing these objectives may be guided by local conservation needs and/or regional goals for establishing a network of MPAs. Conflicting objectives may require negotiation, trade-offs, and consideration of social and economic impacts.
There are multiple goals for establishing MPAs, such as conserving biodiversity, improving fishery management, protecting ecosystem integrity, preserving cultural heritage, providing educational and recreational opportunities, and establishing sites for scientific research. However, the focus of this report is on conserving biodiversity and improving fishery management through the use of
MPAs and marine reserves. To promote biodiversity, the siting criteria for an MPA or reserve may include habitat representation and heterogeneity, species diversity, biogeographic representation, presence of vulnerable habitats or threatened species, and ecosystem functioning. To improve fishery management, site choice may depend on the locale of stocks that are overfished to provide insurance against stock collapse or to protect spawning and nursery habitat. Alternatively, a site may be selected to reduce bycatch of nontarget species or juveniles of exploited species.
3. Biological and Oceanic Features. Evaluating the suitability of potential sites under these criteria requires the collection and integration of information on the life histories of exploited or threatened species (e.g., location of spawning and nursery sites, dispersal patterns) and the oceanic features of the region. The latter may include water current and circulation patterns, identification of upwelling zones and other features associated with enhanced productivity, water quality (nutrient inputs, pollution, sedimentation, harmful algal blooms), and habitat maps.
4. Site Identification. Distilling the desired properties of an MPA into a zoning plan that specifies size and location of reserves requires matching the biological and oceanic properties to meet the specified objectives. Guidelines and general principles that can be applied to this task are described below.
Choice of sites for MPAs should be integrated into an overall plan for marine area management that optimizes the level of protection afforded to the marine ecosystem as a whole because the success of MPAs depends on the quality of management in the surrounding waters. In coastal areas specifically, MPAs will be most effective if sites are chosen in the broader context of coastal zone management, with MPAs serving as critical components of an overall conservation strategy. Management should emphasize spatially oriented conservation strategies that consider the heterogeneous distribution of resources and habitats. This may include selecting MPA sites based on the location of terrestrial protected areas. For example, locating an MPA adjacent to a national park may provide complementary protections for water quality, restoration of nursery habitat, and recovery of exploited species. Often a single MPA will be insufficient to meet the multiple needs of a region and it will be necessary to establish a network of MPAs and reserves, an array of sites chosen for their complementarity and ability to support each other based on connectivity. Connectivity refers to the capacity for one site to “seed” another location through the dispersal of either adults or larvae to ensure the persistence and maintenance of genetic diversity for the resident protected species.
Sites that meet the ecological and oceanographic criteria must also be evaluated with respect to the patterns of stakeholder use in those areas. Site identifi-
cation should maximize potential benefits, minimize socioeconomic conflicts to the extent practicable, and exclude areas where pollution or commercial development have caused problems so severe that they would override any protective benefit from the reserve and so intractable that the situation is unlikely to improve.
The optimal size of marine reserves and protected areas should be determined for each location by evaluating the conservation needs and goals, quality and amount of critical habitat, levels of resource use, efficacy of other management tools, and characteristics of the species or biological communities requiring protection. The boundaries of many MPAs, such as those in the National Marine Sanctuary Program, have been drawn based on specific topographic features, but deciding on the size of marine reserves (i.e., no-take zones) requires greater consideration of the biological features to meet specific management goals. In many cases, specific attributes of the locale (saltmarsh habitat, spawning and nursery grounds, special features such as coral reefs, seamounts, or hydrothermal vents) will determine the size of an effective reserve. In other cases, the dispersal patterns of species targeted for protection, as well as the level of exploitation, should be considered in deciding how much area to enclose within a reserve. Achieving the various marine management goals out-lined in this report will require establishing reserves in a much greater fraction of U.S. territorial waters than the current level of less than 1%. Proposals to designate 20% of the ocean as marine reserves have focused debate on how much closed area will be needed to conserve living marine resources. The 20% figure was originally derived, in part, from the value fishery managers once recommended for conservation of a fish stock's reproductive potential (i.e., the target spawning potential ratio). For sedentary species, protecting 20% of the population in reserves will help conserve the stock's reproductive capacity and may roughly correlate with 20% of that species' habitat. However, the optimal amount of reserve area required to meet a given management goal may be higher or lower depending on the characteristics of the location and its resident species, as described in Chapter 6 and summarized in Table 6.3 of this report. Size optimization generally will require adjustments to the original management plan based on reserve performance, as determined through research and monitoring. Hence, the first priority for implementing reserve sites should be to include valuable and vulnerable areas rather than to achieve a percentage goal for any given region.
Designating Zones and Designing Networks
Zoning should be used as a mechanism for designating sites within an MPA to provide the level of protection appropriate for each management
goal. In many instances, multiple management goals will be included in an MPA plan and zoning can be used to accomplish some of these goals. These zones may include “ecological reserves” to protect biodiversity and provide un-disturbed areas for research, “fishery reserves” to restore and protect fish stocks, and “habitat restoration areas” to facilitate recovery of damaged seabeds. Frequently, an MPA is established initially to protect a site from threats associated with large-scale activities such as gravel mining, oil drilling, and dredge spoil disposal. Under these MPA-wide restrictions, there is an opportunity to resolve other conflicting uses of marine resources through zoning of areas within the MPA. Networking to provide connectivity (see section “Identifying Locations”) should be considered in both zoning and siting of MPAs to ensure long-term stability of the resident populations.
Monitoring and Research Needs
The performance of marine reserves should be evaluated through regular monitoring and periodic assessments to measure progress toward management goals and to facilitate refinements in the design and implementation of reserves. Marine reserves should be planned such that boundaries and regulations can be adapted to improve performance and meet changes in management goals. There are three tasks that should be included in a well-designed monitoring program: (1) assess management effectiveness; (2) measure long-term trends in ecosystem properties; and (3) evaluate economic impacts, community attitudes and involvement, and compliance.
Monitoring programs should track ecological and socioeconomic indicators for inputs to and outputs from the reserve at regular time intervals. Inputs might include water quality, sedimentation, immigration of adults and larvae of key species, number of visitors, and volunteer activities. Outputs might include emigration of adults and larvae of key species, changes in economic activity, and educational programs and materials. Within the reserve, monitoring efforts should assess habitat recovery and changes in species composition and abundance.
Research in marine reserves is required to further our understanding of how closed areas can be most effectively used in fisheries and marine resource management. Reserves present unique opportunities for research on the structure, functioning, and variability of marine ecosystems that will provide valuable information for improving the management of marine resources. Whenever possible, management actions should be planned to facilitate rigorous ex-
amination of the hypotheses concerning marine reserve design and implementation. Research in reserves could provide estimates for important parameters in fishery models such as natural mortality rates and dispersal properties of larval, juvenile, and adult fish. Other research programs could test marine reserve design principles such as connectivity or the effect of reserve size on recovery of exploited species. Modeling studies are needed both to generate hypotheses and to analyze outcomes for different reserve designs and applications.
Integration of management across the array of federal and state agencies will be needed to develop a national system of MPAs that effectively and efficiently conserves marine resources and provides equitable representation for the diversity of groups with interests in the sea. The recent executive order issued by the White House on May 26, 2000, initiates this process through its directive to NOAA (Department of Commerce) to establish a Marine Protected Area Center in cooperation with the Department of the Interior. The goal of the MPA Center shall be “to develop a framework for a national system of MPAs, and to provide Federal, State, territorial, tribal, and local governments with the information, technologies, and strategies to support the system.” Establishment of a national system of MPAs presents an opportunity
to improve regional coordination among marine management agencies;
to develop an inventory of existing MPA sites; and
to ensure adequate regulatory authority and funds for enforcement, research, and monitoring.
Effective enforcement of MPAs will be necessary to obtain cooperation from affected user groups and to realize the potential economic and ecological benefits. Also, coordination among agencies with different jurisdictions will improve the representation of on-site and off-site user groups so that the general public's cultural and conservation values, as well as commercial and recreational activities, receive consideration. Under current management approaches, these interests are often addressed by different agencies independently of each other and may result in short-term policies that are inconsistent with the nation's long-term goals.
What are the consequences of not developing a national system of marine reserves and protected areas? Are conventional management strategies sufficient to ensure that our descendents will enjoy the benefits of the diversity and abundance of ocean life? One purpose of this report is to compare conventional
management of marine resources with proposals to augment these management strategies with a system of protected areas. Although it may seem less disruptive to rely on the familiar, conventional management tools, there are costs associated with maintaining a status quo that does not meet conservation goals. Hence, our relative inexperience in using marine reserves to manage living resources should not serve as an argument against their use. Rather, it argues that implementation of reserves should be incremental and adaptive, through the design of areas that will not only conserve marine resources, but also will help us learn how to manage marine species more effectively. The dual realities that the earth's resources are limited and that demands made on marine resources are increasing, will require some compromise among users to secure greater benefits for the community as a whole. Properly designed and managed marine reserves and protected areas offer the potential for minimizing short-term sacrifice by current users of the sea and maximizing the long-term health and productivity of the marine environment.