GAO-04-606 Pacific Groundfish: Continued Efforts Needed to Improve Reliability of Stock Assessments

Pacific Groundfish: Continued Efforts Needed to Improve Reliability of Stock Assessments

Threats to US national security will expand and diversify in the coming year, driven in part by China and Russia as they respectively compete more intensely with the United States and its traditional allies and partners. This competition cuts across all domains, involves a race for technological and military superiority, and is increasingly about values. Russia and China seek to shape the international system and regional security dynamics and exert influence over the politics and economies of states in all regions of the world and especially in their respective backyards. - China and Russia are more aligned than at any point since the mid-1950s, and the relationship is likely to strengthen in the coming year as some of their interests and threat perceptions converge, particularly regarding perceived US unilateralism and interventionism and Western promotion of democratic values and human rights.

Ocean harvests have plateaued worldwide and many important commercial stocks have been depleted. This has caused great concern among scientists, fishery managers, the fishing community, and the public. This book evaluates the major models used for estimating the size and structure of marine fish populations (stock assessments) and changes in populations over time. It demonstrates how problems that may occur in fisheries data--for example underreporting or changes in the likelihood that fish can be caught with a given type of gear--can seriously degrade the quality of stock assessments. The volume makes recommendations for means to improve stock assessments and their use in fishery management.

The collapse of cod, flounder, and haddock fish stocks in the Northeast United States has caused widespread concern among managers and fishers in the United States and Canada. The diminishing stocks have forced managers to take strict regulatory measures. Numerous questions have been raised about the adequacy of stock assessment science used to evaluate the status of these stocks and the appropriateness of the management measures taken. Based on these concerns, Congress mandated that a scientific review of the methodology and data used to evaluate these stocks be conducted. In this volume, the committee concludes that although there are improvements to be made in data collection, modeling uncertainty, and communicating between fishers, managers, and scientists, the scientific methods used in the Northeast stock assessments are sound. Recommendations are made on how the stock assessment process can be improved.