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Suggested Citation:"Executive Summary." National Research Council. 2000. Improving the Collection, Management, and Use of Marine Fisheries Data. Washington, DC: The National Academies Press. doi: 10.17226/9969.
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Executive Summary

Marine fish are important as a source of food, an item of commerce, the focus of recreational opportunity, and an element of cultural tradition in the United States and worldwide. Data from marine fisheries can contribute to our understanding of the marine environment and how humans relate to and use living marine resources. A comprehensive understanding of the problems currently challenging marine fisheries science and management requires consideration of both the biological and human dimensions of the fishery management process.

The dynamics of marine fish populations are affected directly by climate change, habitat availability, and water quality, but also are affected by human-influenced factors such as fishing and environmental degradation. In turn, human fishing practices are affected by the dynamics of the marine ecosystem and fluctuations in fish abundance. Thus, a complex relationship exists between fish and fishermen1 that must be maintained to foster the existence of both. At the intersection of these complex interactions are fishery managers, who are required by the Magnuson-Stevens Fishery Conservation and Management Act of 1976 (the Magnuson-Stevens Act) to preserve both fish populations and the human harvesters who depend on these fish. Fisheries management requires high-quality observations and well-supported predictions about the status and dynamics of fish populations, and these will be influenced by and influence human activities. Stock assessment scientists, economists, and social scientists must work with managers to design appropriate methods to collect, manage, and use accurate and precise biological, economic, and social data to accomplish their management responsibilities.

Fisheries management responsibilities are shared among several partners in the United States. Most of the available information is collected and analyzed by the National Marine Fisheries Service (NMFS) in cooperation with state and interstate agencies. Some international fishery treaty organizations also collect and assess similar types of information. Eight regional fishery management councils formed pursuant to the Magnuson-Stevens Act work with interstate fish-

1  

The committee uses the terms “fisherman” and “fishermen” throughout the report because this is how practitioners of fishing (both male and female) tend to refer to themselves in the United States. Participants in recreational fishing will be referred to as “recreational fishermen” and “anglers.”

Suggested Citation:"Executive Summary." National Research Council. 2000. Improving the Collection, Management, and Use of Marine Fisheries Data. Washington, DC: The National Academies Press. doi: 10.17226/9969.
×

ery commissions, treaty organizations, and states to implement fisheries management based on “best scientific information available” (required by National Standard 2 of the Magnuson-Stevens Act). Commercial and recreational fishermen participate to varying degrees in different fisheries by helping NMFS collect data. Participants in fisheries management often refer to fishery-independent data (collected by a resource agency, independent from fishing activities and using scientific sampling methods) and fishery-dependent data (measures of directed commercial and recreational fishing activity).

ORIGIN OF STUDY AND COMMITTEE APPROACH

This study reflects NMFS' desire to have the National Research Council assess methods for improving data for stock assessments and fisheries management, and a more specific interest by Congress to have the summer flounder stock assessments reviewed. The two objectives formed the two parts of this study.

Congress requested a one-time study of summer flounder stock assessments by the National Academy of Sciences as part of a conference report that accompanied the Departments of Commerce, Justice, and State, and the Judiciary and Related Appropriations Act of 1998 (PL 105-119). The following statement of task was developed to make the committee 's work more useful nationally and to address the issue of data quality, which the NRC (1998a) identified as a major factor in the performance of stock assessment models:

This study will evaluate the use of data in fish stock assessments and fishery management, including a variety of issues that range from those specific to summer flounder to more generic topics of data use for assessments of marine fish stocks. These issues will include methods of commercial data collection; accuracy and precision of fishery-independent surveys; institutional arrangements for data collection, analysis, and sharing among state and federal agencies; and appropriateness of data quality control procedures.

The congressional request to review the summer flounder assessments resulted from industry concern that NMFS had underestimated summer flounder stock size. Such a review also serves as an example of how fisheries data are used to provide assessment advice in general, how the quality of the data may affect the advice, and how public perceptions of data and assessments can affect their acceptance. Thus, the report first reviews the 1996 and 1999 assessments2 of summer flounder and then uses the insights this review provides to help develop ideas on the appropriate collection of fisheries data more generally. Of course, not all stocks are distributed, exploited, or managed in the same way as summer flounder, nor are they all assessed with similar data sets. For example, groundfish in East Coast fisheries (including summer flounder) are sampled more frequently than fish in other regions, so it is important to recognize that summer flounder data are more extensive than those for many other species on the East Coast and fish species from other regions. Some species on the U.S. West Coast are surveyed only once every three years, whereas some U.S. fish stocks are not surveyed at all. Data requirements may be different for other species, but a practical example provided by the summer flounder fishery provides insight and force to the committee's broader recommendations later in the report.

Evaluation of the Summer Flounder Assessments

The summer flounder fishery was used as a case study for broader data issues of greater interest to NMFS. Summer flounder is a particularly appropriate focus of a case study because

2  

The committee first reviewed the 1996 assessment and used 1996 data for analyses in Chapter 2 because the 1999 assessment was not available until late in the project.

Suggested Citation:"Executive Summary." National Research Council. 2000. Improving the Collection, Management, and Use of Marine Fisheries Data. Washington, DC: The National Academies Press. doi: 10.17226/9969.
×

this species supports a fishery that spans the state waters from Maine to North Carolina together with the U.S. exclusive economic zone adjacent to the waters of these states. This area is targeted by both commercial and recreational fishermen, and has an abundance of data available for assessments. The committee fully reviewed the summer flounder stock assessments of 1996 and 1999 and held public meetings to learn the concerns of commercial fishermen, recreational fishermen, and environmental advocacy groups related to the summer flounder assessments. The committee evaluated the summer flounder assessments using different stock assessment models as a means to explore issues related to the summer flounder data.

Broader Data Collection and Analysis Issues

The broader issue of the need to improve the quality of data used in stock assessment was highlighted in the NRC report entitled Improving Fish Stock Assessments (NRC, 1998a), which showed that the quality of data used in five stock assessment models was more important than the particular model used. The present committee examined all forms of data available for stock assessments and fisheries management, including data from fishery-independent surveys, fishery-dependent data from commercial and recreational fishermen, and auxiliary data collected from a variety of other sources. The committee also examined traditional and new methods for collecting data, and discussed the current state of data management and several new developments in data collection and management.

FINDINGS AND RECOMMENDATIONS

Review of Summer Flounder Stock Assessments

Three analyses of summer flounder data by three individuals using three stock assessment models yielded the same general trends indicated by the 1999 NMFS assessment. These analyses showed that the spawning stock biomass had recovered substantially from a trough in the early 1990s, and that fishing mortality3 dropped substantially in the same period. The committee believes that both changes are probably due to strict management measures implemented in 1992.

The models yielded some differences in predictions that are relevant to summer flounder management. These differences probably arose because there are assumptions in each modeling method that are not explicitly stated, but that affect model results. Thus, it is especially important to document all assumptions made within these complex models—whether explicit or implicit.

First, the model predictions of spawning stock biomass vary somewhat over time, especially in the most recent years. Some models indicate that the biomass has peaked and is falling again. This variability in the estimates of summer flounder biomass should be considered in managing the fishery, taking into account the range of possible spawning stock estimates from the models. All model biomass estimates are lower than the NMFS estimate.

Second, estimated fishing mortality rates varied greatly among the models. This result has implications for fishery managers in terms of how well they may be able to meet quantitative management targets, called biological reference points, based on fishing mortality rates. In the last year of the series, each method produced almost the same estimate of fishing mortality, all of which are above the fisheries management target level of fishing mortality (0.24 year-1). The bottom-line conclusion of the committee's review of the summer flounder assessments is that the managers responsible for this species should be aware of the uncertainty that arises from the choice of model and should manage more cautiously (e.g., reducing fishing mor-

3  

Fishing mortality is a measure of the rate of removal of fish per unit of time from a population by fishing. Fishing mortality, expressed in a variety of ways, is a major fishery management indicator (see Box 1-2).

Suggested Citation:"Executive Summary." National Research Council. 2000. Improving the Collection, Management, and Use of Marine Fisheries Data. Washington, DC: The National Academies Press. doi: 10.17226/9969.
×

tality) in the presence of such uncertainty. This will generally require that they be somewhat more protective of fish stocks. Stock assessment scientists responsible for summer flounder should investigate how differences among model estimates arise and whether such differences indicate changes needed in the models or assumptions used.

These model runs were performed using most of the explicit assumptions used in the NMFS analyses, and assumed that NMFS and state surveys accurately portray the summer flounder population. But, what if the assumptions used by NMFS are incorrect? The committee addressed this possibility by analyzing the summer flounder data using the virtual population analysis method a number of times, changing single assumptions for different runs. Through these model runs, the committee came to the following conclusions:

  • There is little direct evidence for the existence of a large number of unsurveyed large summer flounder, as claimed by some in the industry. Nevertheless, it is plausible that NMFS survey methods could miss such fish if larger fish are less susceptible than smaller fish to capture using NMFS trawl gear and methods. The committee demonstrated that this is an important issue in terms of the fishing mortality targets and total allowable catch, and suggested ways that NMFS could try to determine whether there are a significant number of unaccounted-for large summer flounder. If the NMFS surveys are less likely to catch larger fish than smaller fish, the previously documented size difference between female and male summer flounders will also need to be considered in assessments.

The age structure of the summer flounder population is important and its determination will require that NMFS and fishermen work cooperatively. The first stage should be joint trawling exercises by NMFS and commercial fishermen, using both traditional and adaptive sampling techniques, to test the effects of trawl gear and methods on catch. This would be the most direct approach. NMFS could also take additional, less direct steps, such as conducting egg surveys and tagging studies, but these actions could be more expensive and would take years to gather meaningful data. Observers could assist in tagging and recovering tags from fish.

  • Another major need in stock assessments for summer flounder is for NMFS and industry to improve reporting of the discard rate. Because of the effect of discards on estimation of biomass and fishing mortality rates, industry and NMFS need to work together to devise means to encourage accurate reporting. One short-term solution would be to increase observer coverage to a high enough level to provide statistically meaningful estimates of discards. This could be accomplished by allowing fishermen on observed trips to catch more flounder to pay observer costs.

  • Recreational fishing for summer flounder has been contentious during the past several years because of catch overruns in the recreational portion of the fishery. Recreational fisheries have been allotted 40 percent of the total allowable catch, but have taken more than 50 percent in the past two to three years. In part, this has occurred because the population of young fish, those more likely caught by inshore anglers, has rebounded in response to strict management controls. Because recreational data have a several-month lag time between collection and availability for management, overfishing can occur before fishery managers are aware of the problem. This problem is not unique to summer flounder; it is shared with most fisheries that have a significant recreational sector. Effective management cannot be achieved if only commercial fishermen are regulated strictly, while little control is exerted over recreational catches. Anglers, states, regional councils, and NMFS should work together to solve this particularly difficult problem. The ultimate goal should be data collection and management systems that allow in-season management of summer flounder fisheries, if this goal can be achieved cost effectively. In the absence of such a capability, the populations of summer

Suggested Citation:"Executive Summary." National Research Council. 2000. Improving the Collection, Management, and Use of Marine Fisheries Data. Washington, DC: The National Academies Press. doi: 10.17226/9969.
×

flounder can be sustained only by more conservative management of recreational fisheries.

The actions recommended here may seem too extensive to be justified on the basis of the benefits of better data for the summer flounder fishery alone, particularly considering that NMFS must collect data for many other species. The premise of this study, however, is that lessons from the examination of the summer flounder data and assessments can be applied more broadly because summer flounder stocks, like those of many other groundfish species, are subject to both commercial and recreational fishing and cross legal boundaries of many states and the federal exclusive economic zone. The committee recommends that NMFS and the regional councils implement the recommendations of this report as a test of new ways of cooperating with commercial and recreational fishermen to improve both data quality and acceptance of stock assessment results.

Broader Data Collection, Use, and Management

The committee believes that all the participants in fisheries management should take actions to improve the collection, management, and use of fisheries data. The committee developed the following recommendations to Congress, NMFS, the regional councils, interstate commissions, and commercial and recreational fishermen with the objective of improving fisheries data and thereby fisheries management.

Recommendations to Congress

The U.S. Congress affects fisheries science and policy in two primary ways. First, Congress is the architect of the centerpiece of federal fisheries legislation, the Magnuson-Stevens Act. At present, Congress is formulating legislation to reauthorize the Magnuson-Stevens Act, whose funding authority expires on October 1, 2000. The committee recommends several ways in which the reauthorization could improve fisheries data collection, management, and use in the United States.

Second, Congress appropriates funding for NMFS, the regional councils, and interstate and international commissions to carry out their activities related to fisheries science and management. The committee highlights several items for which additional funding could improve fisheries data collection, management, and use and, consequently, fisheries management. Funding for more capable research vessels and for planning a Fisheries Information System are recent examples of positive congressional steps toward modernization of fisheries data.

Fisheries management is based on ad hoc methods of data collection developed over the past 25 years that may no longer lead to the best management. Congress should support and encourage NMFS to re-evaluate its systems of data collection, management, and use, and to conduct research to increase the effectiveness of these activities. Another important need is for a fishery-by-fishery analysis of the costs and benefits associated with data collection and fisheries management.

In the most recent reauthorization of the Magnuson-Stevens Act, Congress requested that NMFS develop a preliminary design for a Fisheries Information System. The committee believes that such a system could improve and standardize the management of U.S. marine fisheries data and thereby help managers understand regional trends and how they fit into the national context. The committee believes that the Fisheries Information System should be funded on an experimental basis for a fixed term, perhaps 10 years, with quantifiable and measurable objectives that can be evaluated at the end of that period.

Congress should continue to support the acquisition and calibration of new NMFS fishery research vessels that are more effective in data collection and handling than the vessels currently available in the aging NMFS fleet. The so-called “fish for research” programs used by NMFS and regional fishery management councils have

Suggested Citation:"Executive Summary." National Research Council. 2000. Improving the Collection, Management, and Use of Marine Fisheries Data. Washington, DC: The National Academies Press. doi: 10.17226/9969.
×

proven to be a useful means of involving commercial fishermen in research and sampling. Congress should continue to support such programs, with the details of implementation left to the discretion of regional councils.

Congress should amend the Magnuson-Stevens Act to limit the confidentiality of commercial data. By providing better access to commercial data, such a step would help managers and scientists better understand the biology, sociology, and economics of fisheries. Sunset periods on confidentiality are logical outcomes of the public ownership of marine fish resources and the public trust responsibilities of NMFS and the regional councils in fisheries management. The proprietary periods may vary by data type (e.g., they may be shorter for fishing locations than for economic data) and by specific fishery, and these periods should be determined cooperatively between fishery managers and stakeholders. As part of the effort to gather and disseminate needed data, Congress should lift the prohibitions in the Magnuson-Stevens Act on collection of economic data (Sec. 303[b][7] and 402[a]).

Recommendations to NMFS

NMFS has many, in some cases conflicting, responsibilities. NMFS and the regional fishery management councils often suffer from a credibility problem and are more or less continuously engaged in conflicts with commercial and recreational fishermen and environmental advocates who disagree with fishery management plans or other aspects of fisheries management. These conflicts range from criticism voiced in regional council meetings and other public meetings to legal challenges to fishery management plans approved by the councils and NMFS. Some of these conflicts are probably unavoidable results of the dynamics of the regulator-regulated relationship between NMFS and fishermen and their different perceived objectives—such conflict is to be expected. Nevertheless, NMFS and fishermen do share a fundamental objective: the long-term sustainable use of marine living resources and the acquisition of whatever data are necessary to achieve this objective. NMFS and fishery stakeholders should work together to resolve their conflicts to achieve “win-win” solutions. Conflicts might be reduced by greater cooperation between NMFS and fishermen in data collection, so that NMFS develops trust in data from commercial and recreational fisheries and fishermen become confident that NMFS provides accurate data and assessments.

NMFS should continue to explore more cost-effective ways of obtaining the fisheries data it needs, including implementing new remote sensing techniques (e.g., hydroacoustics); implementing electronic logbooks and vessel monitoring systems; increasing observer coverage where needed; developing adaptive sampling in appropriate fisheries; and, especially, finding ways to improve commercial data to make it more useful for stock assessments and finding ways to estimate recreational catch more quickly to allow in-season management of recreational fisheries. NMFS also should consider creating mechanisms to obtain advice from commercial and recreational fishermen related to specific data collection policies and procedures. This could be accomplished through a combination of national meetings to discuss national-level policies and regional meetings to discuss data collection in specific fisheries, possibly through each regional council's scientific and statistical committee.

The Marine Recreational Fisheries Statistics Survey (MRFSS) should be fully funded and include all coastal states and territories that request inclusion. NMFS should invest in research related to MRFSS and investigate new ways to enlist recreational fishermen in data collection for routine monitoring and special studies, but only if the agency intends also to fund implementation of the results of the research. It appears that MRFSS funding and staffing levels are adequate only to maintain the existing survey and conduct a minimal amount of research, the results of which are not always implemented in a timely

Suggested Citation:"Executive Summary." National Research Council. 2000. Improving the Collection, Management, and Use of Marine Fisheries Data. Washington, DC: The National Academies Press. doi: 10.17226/9969.
×

manner. Some recommendations have been implemented (e.g., changes in variance estimates), whereas others remain to be implemented (e.g., retention of previously contacted anglers in subsequent surveys).

NMFS should standardize the data sets and protocols included in the proposed Fisheries Information System, using the standards for spatial and other data established by the Federal Geographic Data Committee. The agency should consider moving away from proprietary data management software to software that is available from many vendors and for which data access and analysis routines can be written easily.

NMFS should evaluate the success of commercial data management firms in providing real-time value-added data products for specific operational purposes, and should determine ways to encourage such entrepreneurial activities. At the same time, NMFS should endeavor to obtain useful data from such sources.

The committee identified a number of data collection activities that merit special attention from fishery scientists within both NMFS and the academic community:

  • Developing methods for evaluating the ecological benefits of fish stocks and their role in marine ecosystems.

  • Determining how to minimize changes in the relationship of actual abundance to indices of abundance (e.g., survey, commercial, or recreational catch per unit effort) and misreporting when management systems are changed.

  • Testing adaptive sampling for data collection for both NMFS and industry.

  • Testing electronic logbooks and vessel monitoring systems that offer value-added features to fishermen.

  • Linking environmental, economic, and social data, as well as climate forecasts, to stock assessments.

  • Improving understanding of the functioning of the marine ecosystems affected by fishing activities by studying important non-target species to determine their feeding habits, their distribution, and their prey and predators.

  • Gaining a greater understanding of the economic and social motivations of fishermen so that data from commercial and recreational fisheries can be interpreted correctly.

  • Validating procedures for determining fish ages and identifying stocks.

Recommendations to Regional Fishery Management Councils

Regional councils should be more proactive and innovative in developing mechanisms within fishery management plans that encourage NMFS to work more effectively with commercial and recreational fishermen in data collection. Councils should play a major role in promoting greater use of data from commercial and recreational fisheries by including programs for collecting and using such data in fishery management plans, and working with NMFS to design appropriate mixtures of data collection approaches (e.g., vessel monitoring systems, observers, logbooks). The design and implementation of fishery management plans should include consideration of how data quality might be enhanced and whether data of the required accuracy and precision are available or could be collected in a cost-effective manner. If sufficient data quality is unlikely to be achievable at a reasonable cost for a particular type of management, councils should consider alternative, less data-intensive management systems. Councils should give serious consideration to new “fish for research” programs that could engage fishermen in data collection and research. Councils should obtain the data needed to conduct in-season management of recreational fisheries or, conversely, manage recreational fisheries conservatively enough so that in-season data are not necessary. They should work with NMFS to improve outreach to commercial and recreational fishermen, and should encourage independent review of data collection and stock assessments on a regular basis.

Suggested Citation:"Executive Summary." National Research Council. 2000. Improving the Collection, Management, and Use of Marine Fisheries Data. Washington, DC: The National Academies Press. doi: 10.17226/9969.
×
Recommendations to Interstate Commissions

Interstate commissions should find ways to increase the standardization of state survey data used in federal stock assessments, consistent with important state uses of the data. Commissions should work with NMFS and the states to create and maintain regional databases, and coordinate them through the proposed Fisheries Information System.

Recommendations to Commercial Fishermen

Commercial fishermen are a critical source of data about the fish stocks they depend on, and more generally, about marine ecosystems. Under most existing management systems, however, commercial fishermen have many incentives to misreport catch data and few incentives to provide accurate and complete data. Although the extent of misreporting is hard to quantify, evidence suggests that it does occur. Many improvements in fisheries management will require active participation of commercial fishermen in data collection, including more extensive cooperation in sampling and a reduction in misreporting of commercial data. Commercial fishermen should work with NMFS to obtain accurate and precise measures of the relative abundance of fish stocks, both through commercial data and research surveys. Commercial fishermen could help improve both and it would be to their benefit to do so—the fish stocks on which they depend are more likely to be sustained if both fishermen and managers share the same accurate view of the abundance of fish stocks.

Recommendations to Recreational Fishermen

Recreational fishermen presently play a relatively small and passive role in data collection, although the interest of anglers in participating in fish-tagging studies have been well demonstrated through the efforts of the American Littoral Society and others to tag sportfish. Angler organizations should increase their cooperation with NMFS and academic scientists to assist in routine data collection and scientifically designed, targeted studies, in order to improve the recreational catch data that are needed in stock assessments. Although scientifically designed tagging studies demand careful implementation, they are crucial to the accurate assessment of fish mortality and movement. Angler assistance is particularly important in fisheries that have a significant recreational component, such as the summer flounder fishery.

CONCLUSION

The future of fisheries management will be based on complementary data from fishery-independent surveys, commercial fishermen, and recreational fishermen. A particular need is to improve the quality of data from commercial and recreational fisheries, so that stock assessment scientists can be justifiably confident about using such data in their models. Commercial and recreational sources could provide large quantities of data important for stock assessments and for understanding the social and economic aspects of marine fisheries, but these data are not always useful in their present form. The sustainable use of marine fish resources, and concomitant protection of marine environments, will require new levels of commitment by the public and their representatives in Congress and federal and state governments to fund and carry out appropriate data collection and management.

Suggested Citation:"Executive Summary." National Research Council. 2000. Improving the Collection, Management, and Use of Marine Fisheries Data. Washington, DC: The National Academies Press. doi: 10.17226/9969.
×
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Suggested Citation:"Executive Summary." National Research Council. 2000. Improving the Collection, Management, and Use of Marine Fisheries Data. Washington, DC: The National Academies Press. doi: 10.17226/9969.
×
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Suggested Citation:"Executive Summary." National Research Council. 2000. Improving the Collection, Management, and Use of Marine Fisheries Data. Washington, DC: The National Academies Press. doi: 10.17226/9969.
×
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Suggested Citation:"Executive Summary." National Research Council. 2000. Improving the Collection, Management, and Use of Marine Fisheries Data. Washington, DC: The National Academies Press. doi: 10.17226/9969.
×
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Suggested Citation:"Executive Summary." National Research Council. 2000. Improving the Collection, Management, and Use of Marine Fisheries Data. Washington, DC: The National Academies Press. doi: 10.17226/9969.
×
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Suggested Citation:"Executive Summary." National Research Council. 2000. Improving the Collection, Management, and Use of Marine Fisheries Data. Washington, DC: The National Academies Press. doi: 10.17226/9969.
×
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Suggested Citation:"Executive Summary." National Research Council. 2000. Improving the Collection, Management, and Use of Marine Fisheries Data. Washington, DC: The National Academies Press. doi: 10.17226/9969.
×
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Suggested Citation:"Executive Summary." National Research Council. 2000. Improving the Collection, Management, and Use of Marine Fisheries Data. Washington, DC: The National Academies Press. doi: 10.17226/9969.
×
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Congress has promoted fisheries science for over a century and its involvement in fisheries management took a great leap forward with passage of the Fisheries Conservation and Management Act of 1976. In the past decade, Congress has requested advice from the National Research Council (NRC) on both national issues (e.g., individual fishing quotas and community development quotas) and the assessments related to specific fisheries (Northeast groundfish). This report was produced, in part, in response to another congressional request, this time related to the assessments of the summer flounder stocks along the East Coast of the United States. Following the initial request, the NRC, National Marine Fisheries Service (NMFS), and congressional staff agreed to broaden the study into a more comprehensive review of marine fisheries data collection, management, and use.

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