Sustaining Marine Fisheries





Committee on Ecosystem Management for Sustainable Marine Fisheries

Ocean Studies Board

Commission on Geosciences, Environment, and Resources

National Research Council



NATIONAL ACADEMY PRESS
Washington, D.C. 1999


NATIONAL ACADEMY PRESS • 2101 Constitution Avenue, NW • Washington, DC 20418

NOTICE: The project that is the subject of this report was approved by the Governing Board of the National Research Council, whose members are drawn from the councils of the National Academy of Sciences, the National Academy of Engineering, and the Institute of Medicine. The members of the committee responsible for the report were chosen for their special competency and with regard for appropriate balance.

This study was a Governing Board Theme Initiative project and funded by the Academy Industry Program Fund, the Mellon Fund, and the Casey Fund of the National Research Council, and the Kellogg Endowment Fund of the National Academy of Sciences and the Institute of Medicine. Any opinions, findings, conclusions, or recommendations expressed in this publication are those of the authors and do not necessarily reflect the view of the organizations or agencies that provided support for the project.

Cover art was created by Alfredo M. Arreguin. Mr. Arreguin is an internationally recognized artist who lives in Seattle, Washington. For many years he has painted the world's endangered ecosystems--the jungles and wetlands, as well as the salmon of the Pacific Northwest. His work is displayed in numerous collections, including the National Museum of American Art in Washington, D.C.

Library of Congress Cataloging-in-Publication Data

Sustaining marine fisheries / Committee on Ecosystem Management for
Sustainable Marine Fisheries, Ocean Studies Board, Commission on
Geosciences, Environment, and Resources, National Research Council.

98-58059

Sustaining Marine Fisheries is available from the National Academy Press, 2101 Constitution Avenue, N.W., Lockbox 285, Washington, DC 20055; 800-624-6242 or 202-334-3313 (in the Washington metropolitan area); http://www.nap.edu

Copyright 1999 by the National Academy of Sciences. All rights reserved.

Printed in the United States of America

This report is dedicated

to the memory of committee member

Nathaniel Bingham (1938-1998)

The National Academy of Sciences is a private, nonprofit, self-perpetuating society of distinguished scholars engaged in scientific and engineering research, dedicated to the furtherance of science and technology and to their use for the general welfare. Upon the authority of the charter granted to it by the Congress in 1863, the Academy has a mandate that requires it to advise the federal government on scientific and technical matters. Dr. Bruce M. Alberts is president of the National Academy of Sciences.

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The Institute of Medicine was established in 1970 by the National Academy of Sciences to secure the services of eminent members of appropriate professions in the examination of policy matters pertaining to the health of the public. The Institute acts under the responsibility given to the National Academy of Sciences by its congressional charter to be an adviser to the federal government and, upon its own initiative, to identify issues of medical care, research, and education. Dr. Kenneth I. Shine is president of the Institute of Medicine.

The National Research Council was organized by the National Academy of Sciences in 1916 to associate the broad community of science and technology with the Academy's purposes of furthering knowledge and advising the federal government. Functioning in accordance with general policies determined by the Academy, the Council has become the principal operating agency of both the National Academy of Sciences and the National Academy of Engineering in providing services to the government, the public, and the scientific and engineering communities. The Council is administered jointly by both Academies and the Institute of Medicine. Dr. Bruce M. Alberts and Dr. William A. Wulf are chairman and vice chairman, respectively, of the National Research Council.

Acknowledgment of Reviewers

This report has been reviewed in draft form by individuals chosen for their diverse perspectives and technical expertise, in accordance with procedures approved by the NRC's Report Review Committee. The purpose of this independent review is to provide candid and critical comments that will assist the NRC in making the published report as sound as possible and to ensure that the report meets institutional standards for objectivity, evidence, and responsiveness to the study charge. The content of the final report is the responsibility of the NRC and the study committee, and not the responsibility of the reviewers. The review comments and draft manuscript remain confidential to protect the integrity of the deliberative process. We wish to thank the following individuals for their participation in the review of this report:

While the individuals listed above have provided many constructive comments and suggestions, it must be emphasized that responsibility for the final content of this report rests entirely with the authoring committee and the NRC.

Foreword

Fishery issues continue to receive enormous, and growing, public attention. A particularly good example can be seen in the groundfish fisheries off New England, where increasingly stringent regulations have been implemented to limit the capture of cod, haddock, flounder, and other fishes. Many other marine fisheries are similarly troubled. Yet, despite considerable study, the exact causes of the problems and the means to solve them are often difficult to understand.

The National Research Council's Ocean Studies Board (OSB) has been actively involved in a number of studies related to marine fisheries, leading to such reports as An Assessment of Atlantic Bluefin Tuna (1994), Improving the Management of U.S. Marine Fisheries (1994), and Improving Fish Stock Assessments (1998). The issues presented by studies such as these highlight the need for taking a broad view of fishery problems. Thus, the Ocean Studies Board designed the study that is the subject of this report, assembling a group of experts to produce the broad-based overview presented here. In addition, several topics raised in this volume are currently being explored in greater detail by ongoing OSB study committees including the Committee to Review Individual Fishing Quotas, the Committee to Review Community Development Quotas, the Committee on the Evaluation, Design, and Monitoring of Marine Reserves and Protected Areas in the U.S., and the Committee on Improving the Collection and Use of Fisheries Data.

We look forward to continuing to make the connections between fishery science and policy that are necessary to achieve sustainable resource management.

Kenneth Brink, Chairman
Ocean Studies Board


Preface

Producing this report was a difficult challenge because of the complexity of the issue—that of trying to bring new insights and approaches into the ways that fisheries are viewed and managed. The need for this evaluation is clear. Many of the fisheries of the world's oceans are under threat. These threatened fisheries are important economically, culturally, and for supplying protein to a growing human population. The ecosystems to which the targeted fish, invertebrates, and plants belong provide additional goods and services to society, so they too must be considered in a holistic view of the problem.

It is this holistic viewpoint that we have sought. The Ocean Studies Board committee that produced this report was unusually broad in its expertise and included fishery scientists, ecosystem and population ecologists, fishers, and social scientists, including economists. Its membership includes people from the fishing industry and from nongovernmental organizations. As can be imagined, achieving a convergence of viewpoints among such a diverse group was challenging. However, it is just such a convergence that is necessary, as discussed in this report, to open new approaches to the difficult problem of sustaining marine fisheries.

In addition to the direct input of committee members, we sought advice at a conference in Monterey, California, from a larger group of international experts representing, again, a diversity of approaches. The results of the discussions at that meeting were presented in a recent special issue of Ecological Applications and also importantly influenced the committee's deliberations, as reflected in this report.

The committee also sought advice and insight from a group of fishers and conservationists at two discussion groups, one in Seattle and the other in Washington, D.C. These meetings clearly indicated the history of the problems and the universal desire to find equitable and achievable ways of addressing the issue of the health of fishery resources.

As will be seen in this report, the committee has no silver bullet to offer. The problem is too large and too complex for a single solution. What we do offer is an overview of the problem and the history of its development. We do point to some pervasive parts of the problem that must be addressed and then offer specific approaches, many of which are already in place, that need amplification and further development. Most of all, the committee proposes a new context, an ecosystem viewpoint in which humans are the major player, in which we must proceed in order to have any hope of maintaining sustainable fisheries in a world in which climate is changing and the human population is growing.

Many individuals and organizations helped the committee in its work. We are grateful to scientists around the world who provided us with information, literature citations, and advice. The National Marine Fisheries Service and the United Nations' Food and Agriculture Organization were particularly helpful with documentation.

This study was stimulated by the actions of Mary Hope Katsouros, former director of the Ocean Studies Board. For her extraordinary energy and insights the committee is grateful. We are pleased that the National Research Council (NRC) agreed that this problem is so important that it funded this study from internal sources. The committee also thanks NRC Chair Bruce Alberts and NRC Executive Officer E. William Colglazier for their personal interest in and help with this project. The staff of the Ocean Studies Board provided the usual excellent backup for the project. The committee is especially grateful to project officer David Policansky, the quintessential professional, for his never-flagging, crucial, and substantial input in bringing this report to fruition.

Harold A. Mooney, Chairman
Committee on Ecosystem Management for Sustainable Marine Fisheries



Contents

Executive Summary

     Marine ecosystems are being perturbed by fishing and other human activities. Many marine fisheries are in decline, and the effects of fishing on other ecosystem goods and services1 are beginning to be understood and recognized. In recent years, global marine catches appear to have reached a plateau of about 84 million metric tons2 per year, although total fish production, which includes aquaculture, has continued to increase. In some cases, fisheries have been entirely closed, and in many others it takes increasing effort to maintain catch rates. Fishing is also an economically important international industry, with first-sale revenues of approximately $U.S. 100 billion per year for all fishery products. (Farm-raised and freshwater fisheries account for approximately 25 percent by weight of all fishery products.) Globally, fishery products directly provided approximately 14 kg of food per person in 1996; approximately 28 percent of global fishery products was used for animal feed and other products that do not contribute directly to human food. Although in recent years total fish production has increased faster than the human population, the total from marine-capture fisheries has increased little if at all.

     To evaluate whether current marine-capture fisheries are sustainable, to determine to what degree marine ecosystems are affected by fishing, and to assess whether an ecosystem approach to fishery management can help achieve sustainability, the National Research Council's Ocean Studies Board established the Committee on Ecosystem Management for Sustainable Marine Fisheries. The committee was directed to "assess the current state of fisheries resources; the basis for success and failure in marine fisheries management (including the role of science); and the implications of fishery activities to ecosystem structure and function. Each activity [was to] be considered relative to sustaining populations of fish and other marine resources" (Statement of Task). This report is the product of the committee's study.

SUSTAINABILITY AND ECOSYSTEM-BASED MANAGEMENT

     The sea was long viewed as an inexhaustible supply of protein for human use. But recently, as the potential and actual adverse effects of human activities have become apparent, our views of marine ecosystems have changed. It has become increasingly clear that the ocean's resources are not inexhaustible. And, in addition to direct societal benefits from fishing, ecosystem goods and services have become recognized as valuable and irreplaceable natural resources. These insights have led to a concern regarding sustainability and an interest in the potential of ecosystem-based approaches to fishery management—two major themes of this report.

     In its simplest sense, sustainable use of a resource means that the resource can be used indefinitely. But even a depleted resource can be used indefinitely at an undesirably low level, and perhaps with undesirable consequences. Therefore, by sustainable fishing, the committee means fishing activities that do not cause or lead to undesirable changes in biological and economic productivity, biological diversity, or ecosystem structure and functioning from one human generation to the next. Fishing is sustainable when it can be conducted over the long term at an acceptable level of biological and economic productivity3 without leading to ecological changes that foreclose options for future generations. The desired levels of biological and economic productivity are in part societal decisions, but it is clear that both could be greater than they are today. In many cases, of course, sustainable fishing implies a need to rebuild populations of exploited species and to promote recovery of ecosystems from effects of overexploitation. Ecosystem-based management is an approach that takes major ecosystem components and services—both structural and functional—into account in managing fisheries. It values habitat, embraces a multispecies perspective, and is committed to understanding ecosystem processes. Its goal is to achieve sustainability by appropriate fishery management.

     Humans are components of the ecosystems they inhabit and use. Their actions on land and in the oceans measurably affect ecosystems, and changes in ecosystems affect humans. Thus, sustainability of fisheries at an acceptable level of productivity and of the ecosystems they depend on requires a much broader understanding of appropriate and effective management than has been encompassed by traditional, single-species fishery management.

THE STATUS OF MARINE FISHERIES

     Marine-capture fisheries include commercial, recreational, subsistence, and various small-scale fisheries, with total landings dominated by the commercial sector. In addition to recent reported annual landings of about 84 million t of marine animals (including fish, molluscs, crustaceans, and some other species), marine plants (seaweeds) also are used for food, as well as some marine mammals and turtles. Fishing as a source of food and revenue in less-industrialized countries, traditionally important, has become even more important recently and accounted for 65 percent of the world's catch in 1993.

     In addition to fish and invertebrates that were caught and landed, approximately 27 million t of nontarget animals (bycatch) were discarded each year in the early 1990s (discards were probably less in the late 1990s). Furthermore, fishing causes mortality that is never observed because of illegal fishing, animals that die after escaping from fishing gear, or animals that are killed by abandoned fishing gear. Thus, the biomass of fish and invertebrates killed by ocean fishing (not including aquaculture) probably exceeds 110 million t per year.

     Various estimates have been made of the total productivity of ocean ecosystems and the maximum long-term potential catch of marine animals. Many of the latter estimates are near 100 million t per year, suggesting that the current annual landings of 84 million t plus unreported mortality are near the maximum sustainable. However, considering species interactions, variations in the ability of individual species to withstand fishing mortality, global overfishing, and ecosystem degradation, it is possible that, under present management and fishery practices, the current catch cannot be exceeded or perhaps even continued on a sustainable basis. Considering individual stocks, about 30 percent globally are overfished,4 depleted, or recovering, and 44 percent are being fished at or near the maximum long-term potential catch rate.

     In the United States, commercial marine fishery landings in 1996 were 4.5 million t, worth $3.5 billion (exvessel value, the value of first sales from a vessel). The total economic contribution of recreational and commercial fishing were each approximately $20 billion per year. However, approximately 33 percent of stocks that commercial and recreational fishers depend on were overfished or depleted in 1994, while 49 percent were fished at or near the level where they could yield the maximum long-term potential catch. In 1994, only about 2 percent by weight of total marine landings were from recreational fishing, but for several species recreational landings exceeded commercial landings.

FISHING AND MARINE ECOSYSTEMS

     Fishing and ecosystems interact, and both are affected by environmental changes and other human activities. Fishing obviously has direct effects on fished stocks. It can alter abundance, age and size structure, sex ratio, genetic structure of fished populations, and species composition of marine communities. Many important commercial species are at high trophic levels (they eat other fishes), and their removal can have especially large effects on ecosystems, perhaps out of proportion to their abundance or biomass. Fishing can also affect habitats, most notably by destroying and disturbing bottom topography and the associated benthic communities. Large-scale mariculture activities (farming of fish, shrimp, and other marine organisms)—especially if they are poorly managed—also can affect marine ecosystems through damage to coastal wetlands and nearshore ecosystems associated with the construction of shore-based or nearshore facilities; through contamination of the water with food, antibiotics, and waste; and through the introduction of diseases and exotic genotypes.

     Fishing has had significant effects on many marine ecosystems, including changes in productivity, biological diversity, and provision of ecosystem goods and services. For example, fishing has contributed to large changes in coral-reef ecosystems in the Caribbean, including the death of corals, and it has resulted in significant changes in community structure in the Bering, Barents, and Baltic seas, on Georges Bank, and elsewhere. In combination with environmental changes and other human activities that have led to the degradation of habitats, pollution, and the introduction of exotic species, fishing has had major effects in the Laurentian Great Lakes, San Francisco Bay, and Chesapeake Bay. It seems likely that, unless fishing and other activities are managed better, human effects on marine ecosystems will increase.

     Long- and short-term environmental fluctuations have major effects on the abundances of marine organisms. Some well-known environmental fluctuations are those precipitated by El Niño events, which change the patterns of Pacific Ocean currents and affect global weather every few years. El Niños lead to the intrusion of warm water into high latitudes and major changes in the distribution and abundance of many species. Environmental changes can produce effects similar to those of fishing, and it is often difficult to distinguish them from the effects of fishing. Although they cannot be controlled directly, environmental fluctuations exert a fundamental influence on the behavior of marine ecosystems and must be taken into account by managers. To be sustainable, fishing and fishery management must be flexible and responsive to environmental changes as well as conservative of ecosystem components. Uncertainties about effects of environmental variability should not be used to excuse continued overfishing.

CONCLUSIONS AND RECOMMENDATIONS

Conclusions

     Many populations and some species of marine organisms have been severely overfished. There are widespread problems of overcapacity: there is much more fishing power than needed to fish sustainably. Fishing affects other parts of the ecosystem in addition to the targeted species, and those effects are only now beginning to be understood and appreciated. Other human activities, such as coastal development, have adverse effects on marine ecosystems as well. The effects of these human activities, combined with ecosystem effects of fishing, may well be more serious in the long term than the direct effects of fishing on targeted species. Although societies have been concerned about the effects of fishing on particular populations and species for centuries, recent recognition of the ecosystem effects of fishing has resulted in part from research on ecosystem approaches and has led to calls for the adoption of ecosystem approaches to fishery management to achieve sustainability at a high level of productivity of fish and of ecosystem goods and services.

     The committee concludes that a significant overall reduction in fishing mortality is the most comprehensive and immediate ecosystem-based approach to rebuilding and sustaining fisheries and marine ecosystems. The committee's specific recommendations, if implemented, would contribute to an overall reduction in fishing mortality in addition to providing other protective measures.

     The committee recommends the adoption of an ecosystem-based approach for fishery management whose goal is to rebuild and sustain populations, species, biological communities, and marine ecosystems at high levels of productivity and biological diversity, so as not to jeopardize a wide range of goods and services from marine ecosystems, while providing food, revenue, and recreation for humans. An ecosystem-based approach that addresses overall fishing mortality will reinforce other approaches to substantially reduce overall fishing intensity. It will help produce the will to manage conservatively, which is required to rebuild depleted populations, reduce bycatch and discards, and reduce known and as-yet-unknown ecosystem effects. Although this approach will cause some economic and social pain at first, it need not result in reduced yields in the long term because rebuilding fish populations should offset a reduction in fishing intensity and increase the potential sustainable yields. Reducing fishing effort in the short term is necessary to achieve sustainable fishing. The options lie in deciding how and when to reduce effort so as to reduce economic and social disruption. The options, however, can be exercised only if decisions are made before the resources are depleted.

     Adopting a successful ecosystem-based approach to managing fisheries is not easy, especially at a global or even continental scale. That is why the committee recommends incremental changes in various aspects of fishery management. The elements of this approach, many of which have been applied in single-species management, are outlined below. They include assignment of fishing rights or privileges to provide conservation incentives and reduce overcapacity, adoption of risk-averse precautionary approaches in the face of uncertainty, establishment of marine protected areas, and research.

     When overfishing (including bycatch) has been effectively eliminated, other human activities will be the major threat to fisheries and marine ecosystems. Although those effects are not a major focus of this report, they cannot be totally separated from fishing, and mechanisms involving cross-sectoral institutional arrangements will be needed to protect fisheries and marine ecosystems.

Recommendations

     The following are recommendations to achieve the broad goals and approach outlined above. Appropriate actions need careful consideration for each fishery and each ecosystem.

Conservative Single-Species Management

     Managing single-species fisheries with an explicitly conservative, risk-averse approach should be a first step toward achieving sustainable marine fisheries. The precautionary approach should apply. A moderate level of exploitation might be a better goal for fisheries than full exploitation, because fishing at levels believed to provide the maximum long-term yield tends to lead to overexploitation. Many species are overfished and their productive potential is impaired, even without considering the ecosystem effects of fishing for them. Expanding fisheries to include previously unfished or lightly fished species, such as deep-sea species, is unlikely to lead to large, sustainable increases in marine capture fisheries. Therefore, the committee recommends that management agencies adopt regulations and policies that strongly favor conservative and precautionary management and that penalize overfishing, as called for in the Magnuson-Stevens Fishery Conservation and Management Act of 1976 and the 1996 amendments to that act, often referred to as the Sustainable Fisheries Act of 1996.

     As described in Chapter 5, the committee's recommendation for more conservative and precautionary management requires that the concept of maximum sustainable yield be interpreted in a broader ecosystem context to take account of species interactions, environmental changes, an array of ecosystem goods and services, and scientific uncertainty. This step, although important, will not by itself sustain marine fisheries and ecosystems at high levels of productivity.

Incorporating Ecosystem Considerations Into Management

     Fishery management should take account of known and probable goods and services of marine ecosystems that are potentially jeopardized by fishing. The aim is to sustain the capacity of ecosystems to produce goods and services at local to global scales and to provide equitable consideration of the rights and needs of all beneficiaries and users of ecosystem goods and services.

Dealing with Uncertainty

     Fisheries are managed in an arena of uncertainty that includes an incomplete understanding of and ability to predict fish population dynamics, interactions among species, effects of environmental factors on fish populations, and effects of human actions. Therefore, successful fishery management must incorporate and deal with uncertainties and errors. The committee recommends the adoption of a precautionary approach in cases of uncertainty. Management should be risk-averse. Although research and better information can reduce uncertainty to a degree, they can never eliminate it.

     Many of the problems that fishery managers face are issues concerning long-term versus short-term goals and benefits. Uncertainty in stock assessments and in future allocations of those stocks has led to an emphasis on short-term benefits at the expense of long-term solutions. Uncertainties over shares when allocations allow open competition can compel individuals to adopt a short-term horizon for decisions related to fishing effort and investment. Management incentives and institutional structures must counteract these responses to uncertainty that jeopardize sustainability. This is especially true when stock assessments are uncertain, which makes it harder for managers to hold the line on conservation.

Reducing Excess Fishing Capacity and Assignment of Rights

     Excess fishing capacity (fishing capacity is the ability to catch fish or fishing power) and overcapitalization (capitalization, related to capacity, is the amount of capital invested in fishing vessels and gear) reduce the economic efficiency of fisheries and usually are associated with overfishing. Substantial global reductions in fishing capacity are of the highest priority to help to reduce overfishing and to deal with uncertainty and unexpected events in fisheries. Overcapacity is difficult to manage directly, and usually evolves in management regimes that encourage unrestricted competition for limited fishery resources. Consequently, managers and policy makers should focus on developing or encouraging socioeconomic and other management incentives that discourage overcapacity and that reward conservative and efficient use of marine resources and their ecosystems.

     At the core of today's overcapacity problem is the lack of, or ineffective, definition and assignment of rights in most fisheries. In addition, subsidies that circumvent market forces have contributed significantly to the overcapacity problem in many fisheries. Therefore, the committee recommends for many fisheries a management approach that includes the development and use of methods of allocation of exclusive shares of the fish resource or privileges and responsibilities (as opposed to open competition) and the elimination of subsidies that encourage overcapacity. A flexible and adaptive approach is essential, and careful attention must be given to equity issues associated with such approaches. The committee recommends experimental approaches to community-based fishery management, including the development of virtual communities. This would include research into the establishment of management groups in which participation is based on shared interests in a fishery and its associated ecosystem, with diminished emphasis on where participants live or their direct financial interests.

Marine Protected Areas

     Where they have been used, marine protected areas—where fishing is prohibited—have often been effective in protecting and rebuilding ecosystems and populations of many (but not all) marine species. They often also lead to increases in the numbers of fish and other species in nearby waters. Importantly, they can provide a buffer against uncertainty, including management errors. Permanent marine protected areas should be established in appropriate locations adjacent to all the U.S. coasts. It will be important to include highly productive areas—that is, areas in which fishing is good or once was—if this management approach is to produce the greatest benefits.

     Protected areas will make the most effective contribution to the management of species and ecosystems when they are integrated into management plans that cover the full life cycles and geographic ranges of the species involved. Smaller, fixed protected areas will be most effective for species with life stages that are spent in close association with fixed topography, such as reefs, banks, or canyons. For other species, the degree of effectiveness of protected areas will be related to the importance of fixed topography in various stages of their lives. Wholly or largely pelagic species move according to ocean currents or other factors that are not necessarily related to fixed topographic structures and are thus likely to benefit less from small protected areas.

     The design and implementation of marine protected areas should involve fishers to ensure that they believe the resulting systems will protect their long-term interests and to improve operational integrity. Because attempts to develop marine protected areas in the United States have been strongly opposed by some fishers, the broad involvement of users is a key strategy. Current theory and experience make clear that marine protected areas must be established over a significant portion of the fishing grounds to have significant benefits. Recent calls for protecting 20 percent of potential fishing areas provide a worthwhile reference point for future consideration, and emphasize the importance of greatly expanding the areas currently protected.

     Marine protected areas are not alternatives to other techniques of fishery management and to the other recommendations in this report. They should be considered as only one of a suite of important ecosystem approaches to achieve sustainable fisheries and protect marine ecosystems. For marine protected areas to be most successful as fishery-management tools, their intended purposes must be clearly defined.

Bycatch and Discards

     Bycatch and discards add to fishing mortality and should be considered as part of fishing activities rather than only as side effects. Estimates of bycatch should be incorporated into fishery-management plans and should be taken into account in setting fishing quotas and in understanding and managing fishing to protect ecosystems and nonfished ecosystem components. Reducing fishing intensity on target species can reduce bycatch, often with no long-term reduction in sustainable yield. In some cases, technological developments and careful selection of fishing gear (e.g., bycatch-reduction devices) can be effective in reducing bycatch, and those options should be encouraged, developed, and required where appropriate. More information is needed on discards and on bycatch and their fate (i.e., whether bycatch is retained or discarded and whether discards survive or die).

Institutions

     Effective fishery management requires structures that incorporate diverse views without being compromised by endless negotiations or conflicts of interest. The committee recommends developing institutional structures that promote

     To achieve these goals, the spatial and temporal scales at which the institutional structures operate should better match those of important processes that affect fisheries. Participation in management should be extended to all parties with significant interests in marine ecosystems that contain exploited marine organisms. Institutions should allocate shares in or rights to fisheries, rather than allowing openly competitive allocations. The clear explication of management goals and objectives is a prerequisite to achieving effective and equitable management.

Information Needs

     Better understanding is needed of the structure and functioning of marine ecosystems, including the role of habitat and the factors affecting stability and resilience. This includes attempting to understand mechanisms at lower levels of organization (i.e., populations and communities), long-term research and monitoring programs, development of models that incorporate unobserved fishing mortality and environmental variability (e.g., El Niño events) into fishery models, multispecies models, and trophic models. More research is also needed on the biological effects of fishing, such as the alteration of gene pools and population structures as a consequence of fishing. More research is needed on the conditions under which marine protected areas are most effective, and marine protected areas themselves should be used as research tools as well as for conservation.

     More information is needed on the effects and effectiveness of various forms of rights-based management approaches and other management regimes, on the way people behave in response to different economic and social incentives, and on barriers to cooperation and sharing of information. The committee recommends research into the roles of communities in fisheries management, including the use of community-based quotas and other assignments of rights to communities, and explorations into the feasibility of granting management responsibilities to those engaged in a particular fishery, regardless of their geographical community ("virtual communities").

     The need for more information should not be used as an excuse for inaction; that excuse has contributed significantly to current problems. Enough is known to begin taking action now.



1Ecosystem goods and services are those ecosystem products and processes that directly benefit humans. They include food, breathable air, clean water, fiber, medicines, quality of life, and many other items.

2One metric ton, usually abbreviated t, is 1,000 kg, approximately 2,205 lbs.

3Economic productivity means the generation of net economic benefits or profits.

4By overfishing the committee means fishing at an intensity great enough to reduce fish populations below the size at which they could provide the maximum long-term potential (sustainable) yield (see Chapter 2), or at an intensity great enough to prevent their recovery to that size. As described in this report, it follows that overfishing is a function of population size.

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