Conclusions and Recommendations
~ enlarge ~
Conservation of Marine Resources Requires New Approaches
Globally, there has been a surge of interest in designating areas of the seas as marine reserves and protected areas to maintain and conserve marine species and habitats threatened by human activities. There is a growing consensus that living marine resources require more stringent protections. Crises facing many marine ecosystems are increasing and attracting more public attention. Among these are the recent collapse of the Newfoundland cod fishery, the near-collapse of the groundfish fishery in New England, and the loss of coral reef communities to disease and overfishing. Hence, there is widespread concern among policy-makers, scientists, and the public at large about the current status and uncertain future of marine ecosystems. Better approaches for utilizing and protecting living marine resources are needed; however, choosing the best methods to maintain or restore the health of marine ecosystems is a difficult task for resource managers and a source of disagreement among user groups, scientists, and the conservation community.
One does find general agreement, however, on the shortcomings of most current management policies. For example, conventional fishery management commonly focuses on single species and is concerned with species-specific issues such as maximum sustainable yields, appropriate fishing mortality rates, effects of seasonal closures of certain fishing grounds, and appropriate size lim-
its to protect juveniles and the spawning potential of the stock. Whether or not these single-species management strategies achieve their specific goals, their practice often neglects other important and pervasive problems. Furthermore, regulations designed for one fishery may negatively influence other species on the same fishing grounds through gear conflicts, bycatch, habitat destruction, or subtle but important shifts in predator-prey relationships.
Shortcomings in marine resource management also derive from inadequate coordination among agencies charged with these responsibilities. Frustration rises when conventional approaches fragment management into a myriad of regulations from multiple state and federal agencies, each addressing only one component of the problem. The deficiencies in fishery management and ecosystem protection cannot be overcome by continuation of ocean management on a multijurisdictional basis, in which different species are managed separately, agencies may apply regulations independently of each others, and state and federal policies are not fully coordinated. When this piecemeal approach is followed, the interests of various stakeholders are developed in parallel, some stakeholders receive no representation at all, and instead of integrated management, competing regulations may develop that fail to meet objectives of conservation and sustainable use. Also, this narrowly focused approach to management tends to underrepresent the values of the general public and disproportionately represent organized user groups, whether they are commercial fishers, recreational fishing groups, or dive tour operators.
It is clear that despite good intentions and dedicated effort on the part of resource managers at federal, state, and local levels, most existing strategies to regulate fishing or other removals of living marine resources have neither prevented the decline of these resources nor slowed the destruction of habitat. Increasingly, methods are being sought that preserve ecosystem components essential for the health of marine resources, especially when such overarching factors as genetic diversity, species diversity, spawning biomass, and ecosystem stability require protection. Thus, new approaches are necessary to allow a more integrated and comprehensive attack on problems that transcend the concerns of single-species management.
Marine Reserves and Protected Areas Provide a Strategy for Ecosystem-Based Management
A growing body of literature documents the effectiveness of marine reserves for conserving habitats, fostering the recovery of overexploited species, and maintaining marine communities. There is a rising demand for ecosystem-based approaches to marine management that consider the system as a whole rather than as separable pieces of an interlocking puzzle. Congress recognized this in the 1996 reauthorization of the Magnuson-Stevens Fishery Conservation and Management Act (NOAA, 1996a) and requested that the National
Marine Fisheries Service undertake a study of what such management would entail from a fishery management perspective. The study produced a list of key policy objectives “to change the burden of proof, apply the precautionary approach, purchase insurance against unforeseen adverse ecosystem impacts, learn from management experiences, make local incentives compatible with global goals, and promote participation, fairness, and equity in policy and management.” The report recommends that fishery management councils “use a zone-based management approach to designate geographic areas for prescribed uses. Such zones could include marine protected areas (MPAs), areas particularly sensitive to gear impacts, and areas where fishing is known to negatively affect the trophic food web” (NMFS, 1999).
Networks of marine reserves, where the goal is to protect all components of the ecosystem through spatially defined closures, should be included as an essential element of ecosystem-based management. Incorporation of MPAs, including marine reserves, into a broader plan for coastal and ocean management offers an opportunity to revise current fragmented management approaches and provide for more inclusive representation of stakeholders concerned about the health of marine ecosystems. The performance of MPAs as a conservation tool is best viewed in the broadest context of management objectives that encompass the full range of human interests in the sea. In this sense, management for direct use (e.g., fisheries), for indirect use (e.g., heritage and existence values), and for ensuring protection of essential ecosystem services ultimately must be accomplished through zoning, which requires designating different areas to meet different goals.
Designing Marine Protected Areas
The design of MPAs should proceed through four stages: (1) evaluate needs, (2) set goals, (3) assemble data on the region to be served by the MPAs, and (4) outline various options for siting areas that meet the previously agreed-on goals. Each stage of this process should involve the broad community of stakeholders—users, managers, scientists, conservationists, homeowners, and other concerned members of the public—such that the final MPA plan represents a joint effort between affected communities and management agencies.
Establishment of networks of marine reserves and protected areas will provide an ecosystem-based approach for meeting the multiple objectives of coastal and marine area management. These objectives include protection of habitat, biodiversity, and fisheries and promotion of research to increase the effectiveness of various conservation and management measures such as empirical determinations of fishing and natural mortality rates to improve the accuracy of stock assessment methods used for fishery management.
To Protect Biodiversity
In the design of a system of marine reserves and protected areas, the complete spectrum of habitats supporting marine biodiversity should be included with emphasis on safeguarding ecosystem processes. One of the best-supported goals of MPAs is to conserve and restore marine biodiversity—that is, to maintain species diversity and the natural balance of species interactions. This goal entails (1) setting aside representative areas of each different habitat in a biogeographic region, (2) establishing systems of marine reserves that are interconnected and large enough to be mostly self-sustaining, and (3) including each habitat type in multiple reserves to provide buffers against changing environmental and societal forces. Connectivity among reserves should be a factor in the design of MPA networks to prevent genetic isolation of populations and to ensure that dispersal of early life stages and re-colonization are facilitated. Moreover, properly networked MPAs will promote habitat linkages necessary for various life stages and ensure continuity of life processes within the MPA network.
To Improve Fisheries Management
Another prominent goal of marine reserves and protected areas is to make fishery management more effective. Fishery reserves can be used to address one or more of the following objectives, dependent on the needs of the fishery:
1. Allow depleted fisheries to recover from overfishing. Establishment of reserves to restore depleted fisheries will generally show the largest increases in abundance, size, and age structure of fish stocks within their boundaries, compared to unprotected areas. Fishers are more likely to accept reserves as an alternative management option when stocks are severely overexploited.
2. Prevent the collapse of fish stocks. Appropriately designed and implemented reserves can help to prevent severe overexploitation of some fishery resources. Reserves that enclose critical habitat (e.g., nursery or spawning habitats) will be most effective in promoting these fishery management goals.
3. Improve sustainable yield of fisheries. For some stocks, the spillover of juveniles and adults from reserves to fishing grounds has the potential to enhance the long-term yield of the fishery. However, evaluation of age- and sizespecific dispersal probabilities is essential and critical to understand this enhancement potential. Some reserves may serve as source areas, replenishing depleted or heavily fished stocks in areas that remain open to fishing. In this case, the reserve must be large enough to protect the population within its boundaries, but not so large that dispersal to the surrounding area is limited. Similarly, the reserve should be sited such that oceanographic features provide both sufficient productivity to support protected populations and favorable currents to facilitate appropriate adult and larval spillover to open areas and other reserves. An area designated as an ecological reserve may not export all species of fish to
the surrounding area but may still benefit these fisheries indirectly by supporting biodiversity and other ecosystem services. However, even an effective reserve design may not overcome the danger that there will be increased fishing pressure on unprotected populations in the open areas.
4. Reduce bycatch of nontargeted species and undersized individuals of targeted species. Properly designed reserves can protect small fish and other species that otherwise would be caught and killed unintentionally. Frequently, by-catch includes young individuals of a target species—this reduces the size and productivity of the population available to the fishery in subsequent years. Such protection will not only improve the productivity of targeted species but also help maintain the structural and functional integrity of marine communities. Likewise, reserves can help protect threatened or endangered species (e.g., marine mammals and seabirds) either directly by reducing bycatch or indirectly by protecting their food sources.
Marine reserves may provide the only effective means to ensure against overfishing of some species if exploitation is high and there is substantial uncertainty in the stock assessments. Empirical and modeling studies demonstrate that reserves are effective in increasing the population density, biomass, and age structure of species that have limited adult mobility such as benthic invertebrates and some demersal fishes. Conventional management of such species often fails because they have life-history characteristics that are difficult to evaluate using standard stock assessment methods. As an example, rockfishes (Sebastes spp.), in addition to low adult mobility, have the following life-history characteristics: extreme longevity, low natural mortality, infrequent recruitment success, low productivity, habitat specificity, and co-occurring species that are fished as an assemblage. In such fisheries, large reserves may prove the most effective means of regulating fishing because a portion of the population is protected independently of the accuracy of the stock assessment.
Modeling studies on several fish species indicate that reserves would have to be extremely large if they were the only or the primary means to maintain fishing rates within sustainable levels. These models predict that the open area should encompass the fraction of the population that could be sustainably fished. Smaller area closures may be sufficient when used in concert with more conventional means of limiting fishing effort. The question of how much fishing ground to close will thus depend on the effectiveness of fishery regulations in open areas. Because of the diversity of fish species and management objectives, it is impossible to set a universal percentage for area closure. Models that incorporate species-specific parameters have derived values ranging from 10% to 80% closure of fishing grounds. Future modeling studies should evaluate the relative performance of a suite of management strategies, including reserves, to regulate landings and fishing mortality rates. These studies should be conducted for specific fisheries, using detailed models to represent the spatial dynamics of
populations and fishing effort, while incorporating realistic assumptions about the performance of other methods to control fishing.
To Balance Costs and Benefits
When comparing marine reserves to conventional management, the contribution of reserves to the conservation of biodiversity should be included in the assessment of the costs and benefits of regulating fisheries. In some circumstances it is possible that reserves will yield both classes of benefits simultaneously, but in other cases there will be trade-offs and conflicts between fishery management and conservation of biodiversity. Where trade-offs and conflicts exist, policymaking requires assessment, forecasting, and analysis of how reserves will affect both biodiversity and fisheries. Increased research on the valuation of the full range of potential costs and benefits will be needed to accurately assess the economic impacts of marine reserves.
Whenever benefits of a management approach are discussed, measurements of success must take into account the time paths of benefits and costs as well as the possible changes in the distribution of benefits and costs among different members of the community over time. For instance, reduced fishing access with institution of an ecological reserve may represent an immediate cost to fishers—a cost remaining in play until, and if, the fishery in question regenerates from the protective effects of the reserve, whereas members of the community supported by ecotourism may benefit immediately.
If benefits are defined strictly in terms of market values, the following circumstances might lead to MPAs and reserves providing no net economic gain:
1. where financially profitable activities are displaced by valuable human uses that do not generate financial profits,
2. where the absence of resource security generates incentives to engage in destructive short-term activities rather than sustainable long-term use of marine natural resources,
3. where the costs of enforcement exceed the financial benefits, and
4. where displacement of fishing effort (or other activities) results in a disproportionate degradation of surrounding areas.
In any analysis of costs and benefits, however, it is important to include the nonmarket benefits of preserving the naturalness of ocean areas.
To Complement Other Management Efforts
In designing MPAs and reserves for conserving biodiversity and managing fish stocks, it is important to recognize that the goal is to maintain the health of marine ecosystems beyond the relatively small area protected with-
Page 180in reserves. MPA networks can provide a key component of precautionary management frameworks to help secure the long-term persistence of species and ecosystem processes, as well as offer support to fisheries. However, even with closures of representative areas within a given biogeographic zone, the surrounding area will remain vulnerable to the destructive aspects of human activities. Realistically, core ecological reserves will have to be supplemented by additional measures, including conventional fishery regulations in open areas as well as prohibitions on damaging activities that have been poorly regulated in the past.
To Protect a Sufficient Fraction of Marine Habitats
The amount of area needed in MPAs and reserves to preserve ecosystem functioning will depend upon the effectiveness of resource management and environmental regulations both within and outside the MPAs. The complexities and uncertainties of managing living marine resources have fueled the debate over what fraction of the ocean should be fully protected in marine reserves. There has been much discussion of the need for closure of 20% of the seas, sometimes expressed as 20% of the management area, 20% of the exclusive economic zone (EEZ), or 20% of each major ecosystem. This figure was derived initially from a fishery stock assessment model used to determine the level of spawning biomass1 required to sustain the stock and augmented by attempts to estimate the amount of habitat needed to support fisheries and biodiversity. But, the primary consideration for implementing marine reserves should be the needs of each biogeographical region based on protecting critical habitats (such as spawning grounds, nursery grounds, or other areas harboring vulnerable life stages) and special features (such as seamounts, hydrothermal vents, and coral reefs). The extent of a particular area that needs protection will be determined by the quality and amount of habitat, the current health of the living resources, the efficacy of other management tools, and the rarity of the species to be protected.
An incremental approach to implementing MPAs and reserves should be adopted to protect the areas with the highest conservation needs and greatest ecosystem impact first, with additional areas added as necessary to meet management goals. Although protection of 20% of a management area may be suitable for some circumstances, the fraction of area required will vary by region and management goal. The primary emphasis should be on protection of valuable and vulnerable areas, rather than on achievement of a percentage goal for any given region.
1 Spawning biomass refers to the biomass of mature females.
Implementing Marine Reserves and Protected Areas
Integrating Habitat and Resource Protection with Human Needs and Values
Choosing a location for a marine reserve or protected area requires an understanding of probable socioeconomic impacts as well as the environmental criteria for siting. The suite of studies, recommendations, and management policies involved in the design of reserves for protection of biodiversity and fishery stocks must be tightly integrated with socioeconomic analysis. Adequate consideration of socioeconomic issues will be essential for building public support for MPAs and reserves, without which they will be difficult to implement and enforce.
The economic health of coastal communities depends inherently on the health of the waters that border them. A robust marine ecosystem is valuable not only for fishing, but also for recreation, tourism, and the natural scenic attractions that make the seashore such a desirable place to live and vacation. Thus, in many cases the design of MPAs must consider the socioeconomic issues entailed in coastal land use, issues that loom with increasing importance as larger numbers of people elect to live on our coastlines.
It is essential to involve all potential stakeholders at the outset to develop plans for MPAs that enlist the support of the community and serve local conservation needs. A fundamental lesson learned from experience throughout the world is that attempts to implement MPAs in the absence of general community support invariably fail. Inclusion of “bottom-up” or “grass-roots” approaches to planning, design, and implementation of MPAs offers the best opportunity to develop plans with the endorsement of local communities. Three major steps are necessary for effective public participation: (1) identify all stakeholders; (2) assess the needs and concerns of the affected communities; and (3) involve stakeholders in MPA planning, design, and implementation. When communities have a voice and are incorporated into the MPA planning process, they are more likely to share critical knowledge and develop an interest in the long-term success of the MPA.
When identifying stakeholders, it is important to recognize that there are many people in addition to traditional user groups who take an interest in the health of the marine environment. Both on-site and off-site constituents value aesthetics, biodiversity, and conservation. Their views and values should be assessed for prospective MPA locations that include different types of cultural and commercial resources, such as coral reefs, kelp forests, whale habitats, fish spawning sites, or other habitats critical for the survival and productivity of marine species. Such evaluations ought to be conducted in an interdisciplinary setting, with marine scientists, social scientists, survey design specialists, and valuation economists. Results of this type of research would help to properly
weigh the public good benefits of MPAs, benefits that tend to be underrepresented in a political process often dominated by more readily quantified user benefits and costs, such as fisheries.
Systematic social studies should be conducted to accurately evaluate the impacts of a proposed MPA on community stability. The overall impact of an MPA on a community may be positive or negative or may simply involve shifts of resources from one community sector to another. Because the impact of an MPA will change over time, the effects on different communities will require assessment over many years. Impact assessment will require analysis of multigenerational attitudes, rather than “snapshot” surveys, to determine the cultural commitments to marine areas.
Monitoring MPA and Reserve Performance
Marine reserves and protected areas must be monitored and evaluated to determine if goals are being met and to provide information for refining the design of current and future MPAs and reserves. As in other resource management situations, the ability to adapt or modify existing MPAs is important to optimize benefits from this management tool. Monitoring and evaluation will also contribute to our basic understanding of marine ecosystems. Indeed, in many cases, marine reserves especially will facilitate important experiments in marine ecology, often at spatial and temporal scales that are unusual in ecological research.
The basic knowledge gained from marine reserves about structure, function, and variability in marine ecosystems will enhance our abilities to design reserves and allow more accurate evaluations of their ecological and socioeconomic consequences. Reserves also allow more accurate estimation of parameters such as natural mortality rates—an essential variable in stock assessment models used to manage fisheries. Without such information, assessments may prove unreliable; hence, regulations based on these assessments are more likely to be challenged either by the fishing industry or by conservationists.
Research in marine reserves and protected areas will help answer questions such as the following with regard to both ecological and socioeconomic performance:
1. What are the impacts of closures on species within reserves and in adjacent open areas?
2. What are the dispersal potentials for adults and early life stages of commercially or ecologically significant species?
3. How do differences in reserve boundary or area ratios affect dispersal?
4. How do oceanographic features influence reserve performance?
5. What are the relative impacts of natural variability and human activities on ecosystem functioning (using comparative studies of reserves and areas open to human use and exploitation)?
6. How do closures affect various user groups, including the interests of future generations?
7. Do attitudes and compliance change over time in communities bordering reserves?
Fishery and resource managers should develop and implement management policies that place more emphasis on spatial approaches to experimentally “explore” their systems and to increase our understanding of how fishing impacts the ecosystem. Much of the research described above will further our understanding of the spatial dimension of fishing and enhance our use of spatial management tools, including rotating fishing zones, experimental policy zones, temporary recovery areas, and spatially limited entry licenses and quotas. Such tools have been applied sparingly in marine fishery management, but they are likely to be valuable approaches for controlling effort and fishing mortality. Also, spatial tools have the potential to allow simultaneous comparisons of different regulatory policies using zoning to delineate replicated management areas. This is necessary to account for the interannual variability in conditions that also affect resources. Thus, instead of relying on uniform, fishery-wide, steady-state policies and statistics, managers and fishery scientists could separate areas for different fishing “treatments” without necessarily reducing the targeted yield for the fishery. In this model, reserves serve as controls to provide baseline values for management experiments.
Also, fishery managers should develop data-gathering systems that enable finer spatial analysis of exploited ecosystems. Many fishery management systems now utilize aggregate and fishery-wide data gathering. Increasing the emphasis on spatial regulations will require more consideration of the location of fishing activity and more spatially oriented stock assessment tools. Modern global positioning system (GPS) technology, vessel monitoring systems (VMSs), and data entry systems are in place in many fisheries already. The use of these tools should be encouraged and expanded, with the aim of increasing the understanding of the spatial and temporal distribution of fishing activity and yield.
Supporting MPAs Through Institutional Coordination
The design, implementation, and monitoring of MPAs and reserves require effective institutional structures at federal, state, and local levels of management. Regional coordination of management will be required to establish networks of MPAs and to designate zones for specific uses. As emphasized earlier, fragmented management policies may result in different agencies working at cross-purposes. Hence, integration of management among agencies is essential, and current programs should work together to develop a policy on MPAs. In developing this policy, agencies should recognize all groups with strong interests in the sea, ensuring opportunities for input from those concerned with biological diversity, ecosystem functioning, and the protection of the nation's ma-
rine heritage. At the federal level, these agencies would include the National Marine Fisheries Service, National Marine Sanctuaries, and National Estuarine Research Reserves (National Oceanic and Atmospheric Administration), the National Estuary Program (Environmental Protection Agency), the Fish and Wild-life Service, and the National Park Service (Department of the Interior) established under federal legislation, and equivalent agencies at the level of the states and territories. Existing programs should be used both as starting points in establishing a comprehensive system of MPAs and as vehicles for monitoring and evaluating the impacts of MPAs and reserves on fisheries, biodiversity, and ecosystem functioning.
The potential economic and ecological benefits of marine reserves and protected areas will not be realized without a sufficient commitment to enforcement and monitoring. To maintain programmatic integrity and public support for marine reserves and protected areas, it is necessary that sufficient regulatory authority and funds for enforcement, research, and monitoring be provided to implement management plans. Effective enforcement of reserves is essential to sustain cooperation from the general public and affected user groups. Upgraded monitoring programs will ensure that robust data are collected for application both locally and regionally. Results from monitoring programs should be integrated with research programs for the evaluation of reserve performance and design of more effective marine reserves.
MPAs should be developed as a component of broader coastal zone and continental shelf management. This approach represents a shift toward more spatially explicit management of marine resources in recognition of the need to protect areas representative of the complete range of marine species and habitats. Finally, the management system should be adaptable so that the knowledge gained from research and monitoring can be applied to improve performance through more effective design.
Sufficient scientific information exists on the habitat requirements and life-history traits of many species to support the implementation of marine reserves and protected areas to improve management. Given the complexity of natural ecosystems and the broad range of conservation objectives, there are bound to be uncertainties about the optimal design of MPAs, particularly when they include ecological and fishery reserves. However, these uncertainties should not be used as an excuse for failing to take action. Even the most thorough studies of MPAs and reserves, or other management tools, will not eliminate uncertainties with respect to performance. Rather, optimization in the design of MPAs and reserves will depend on an iterative process that combines careful planning with experience. Prevention of the continuing erosion of quality in the marine environment is a shared global concern that requires fresh approaches to management, including MPAs. MPAs, including marine reserves, should be more broadly implemented to improve management of the marine environment and ensure that future generations will benefit from the ocean's bounty.