Science and Its Role in the National Marine Fisheries Service (2002) / Chapter Skim
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2. Adequacy of NMFS Data, Scientific Foundations, and Models
2. Adequacy of NMFS Data, Scientific Foundations, and Models
Pages 15-25
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From page 15... ...
NMFS allocates a substantial portion of its personnel and resources to stock assessment, and the resulting assessments form the basis of biological reference points and management decisions, such as quotas, restriction of effort, and closing of seasons or areas to fishing. Previously, study committees sponsored by the National Research Council have conducted reviews of stock assessments, including reviews at the species level (such as Atlantic bluefin tuna, NRC, 1994; Pacific salmon, NRC, 1996b)
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From page 16... ...
Scientists and non-scientists view uncertainty differently, but this does not justify ignoring stock assessment advice, just as it would not justify ignoring weather predictions, national economic forecasts, or health advisory alerts. Data In stock assessments, constant attention must be given to how fisheries data are collected and how they are used.
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From page 17... ...
Observer programs are expensive, and their use is mandated for specific fisheries, such as the Georges Bank scallop fishery, and in fisheries that have interactions with protected species. Observer coverage is used for commercial fisheries and is virtually nonexistent for recreational fisheries.
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From page 18... ...
Fishing boats continue to catch multiple species of fish at the same time, but they are compelled by regulation to discard a greater percentage of the protected species. As bocaccio and lingcod fishing allowances have decreased in recent years, it is therefore, as both sides agree, a virtual certainty that the bycatch mortality rates for each fish have in turn increased.
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From page 19... ...
The statistical-survey methods (NMFS Marine Recreational Fishery Statistics Survey) that have provided reliable data estimates have been slow, with many months passing between harvest by the angler and complete catch and effort estimation by NMFS.
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From page 20... ...
The NMFS Ecosystem Principles Advisory Panel recommended the development of fisheries ecosystem plans to modify single-species approaches to incorporate ecosystem attributes, evaluate how trophic interactions and oceanographic processes affect recruitment, document the role of habitat in supporting fisheries and ecosystem productivity, and develop aggregate models that can be used to predict single-species and ultimately multispecies harvest objectives (NMFS, 19991. The committee encourages the development of such plans because they
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From page 21... ...
Information could increase understanding and result in better management of the fish resources. NMFS should facilitate greater cooperation among fisheries scientists, regional fishery management council advisory panels, fishery participants, and other stakeholders to improve the quality and efficiency of data collection and create a shared sense of confidence in what the data indicate.
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From page 22... ...
. Modeling Stock-assessment modeling not only provides an important structure for synthesizing information and determining fish abundances but also serves as a useful predictive tool to evaluate alternative management scenarios and the consequences of potential actions before they are implemented.
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From page 23... ...
Several examples have been given in this regard here and in previous NRC reports, for example applying alternative assessment models to evaluate the effects due to model assumptions and structure, using survey variance to appropriately weigh observations going into assessments, providing confidence bounds or posterior distributions for current biomass and total allowable catch (TAC) estimates, determining costs and
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From page 24... ...
As pointed out in the NRC report Sustaining Marine Fisheries (NRC, 1999b) , "ecosystem-based management is an approach that takes major ecosystem components and services both structural and functional into account in managing fisheries.'' Important ecosystem-level factors that consider predator-prey relationships and marine habitats should be considered, even in single-species models that foster precautionary, riskaverse management.
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From page 25... ...
Harvest strategies can be explored in a theoretical context through modeling and can be compared with other strategies to help form a basis of decision-making. In recognition that a wide variety of potential harvesting strategies and decision rules exist, it is sensible to explore management options.
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