Criterion 1: Inherent Vulnerability to Fishing
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Pacific Salmon Chinook salmon (Oncorhynchus tshawytscha) Chum salmon (Oncorhynchus keta) Coho salmon (Oncorhynchus kisutch) Pink salmon (Oncorhynchus gorbuscha) Sockeye salmon (Oncorhynchus nerka) Image © Scandinavian Fishing Yearbook / www.scandfish.com Alaska February 25, 2005 Updated April 25, 2011 Matthew Elliott Consulting Researcher Disclaimer: Seafood Watch® strives to have all Seafood Reports reviewed for accuracy and completeness by external scientists with expertise in ecology, fisheries science and aquaculture. Scientific review, however, does not constitute an endorsement of the Seafood Watch® program or its recommendations on the part of the reviewing scientists. Seafood Watch® is solely responsible for the conclusions reached in this report. About Seafood Watch® Monterey Bay Aquarium’s Seafood Watch® program evaluates the ecological sustainability of wild-caught and farmed seafood commonly found in the United States marketplace. Seafood Watch® defines sustainable seafood as originating from sources, whether wild-caught or farmed, which can maintain or increase production in the long-term without jeopardizing the structure or function of affected ecosystems. Seafood Watch® makes its science-based recommendations available to the public in the form of regional pocket guides that can be downloaded from www.seafoodwatch.org. The program’s goals are to raise awareness of important ocean conservation issues and empower seafood consumers and businesses to make choices for healthy oceans. Each sustainability recommendation on the regional pocket guides is supported by a Seafood Report. Each report synthesizes and analyzes the most current ecological, fisheries and ecosystem science on a species, then evaluates this information against the program’s conservation ethic to arrive at a recommendation of “Best Choices,” “Good Alternatives” or “Avoid.” The detailed evaluation methodology is available upon request. In producing the Seafood Reports, Seafood Watch® seeks out research published in academic, peer-reviewed journals whenever possible. Other sources of information include government technical publications, fishery management plans and supporting documents, and other scientific reviews of ecological sustainability. Seafood Watch® Research Analysts also communicate regularly with ecologists, fisheries and aquaculture scientists, and members of industry and conservation organizations when evaluating fisheries and aquaculture practices. Capture fisheries and aquaculture practices are highly dynamic; as the scientific information on each species changes, Seafood Watch’s sustainability recommendations and the underlying Seafood Reports will be updated to reflect these changes. Parties interested in capture fisheries, aquaculture practices and the sustainability of ocean ecosystems are welcome to use Seafood Reports in any way they find useful. For more information about Seafood Watch® and Seafood Reports, please contact the Seafood Watch® program at Monterey Bay Aquarium by calling 1-877-229-9990. 2 Table of Contents I. Executive Summary……………………………………………………………………….3 II. Introduction………………………………………………………………………………..7 III. Analysis of Seafood Watch® Sustainability Criteria for Wild-caught Species…………12 Criterion 1: Inherent Vulnerability to Fishing Pressure………………………………….12 Criterion 2: Status of Wild Stocks……………………………………………………….38 Criterion 3: Nature and Extent of Wild Stocks…………………………………………..73 Criterion 4: Effect of Fishing Practices on Habitats and Ecosystems…………………...96 Criterion 5: Effectiveness of the Management Regime………………………………...104 IV. Overall Evaluation and Seafood Recommendation…………………………………….114 V. References………………………………………………………………………………116 VI. Appendix 1……………………………………………………………………...125 Seafood Watch® Wild Pacific Salmon Report April 25, 2011 I. Executive Summary This seafood report evaluates the ecological sustainability of wild-caught Alaska salmon. To make an overall recommendation, salmon fisheries have been analyzed using Seafood Watch’s five basic criteria: inherent vulnerability to fishing pressure, status of wild stocks, nature and extent of bycatch, effects of fishing methods on habitats and ecosystems, and effectiveness of the management regime. Inherent Vulnerability Salmon have natural reproductive traits that imply a biological resilience to overfishing. They are relatively short-lived animals (two to five years on average) that release large numbers of eggs when spawning, indicating a high potential reproductive rate. However, the dependence of salmon on specific freshwater areas leaves them susceptible to habitat loss and concomitant population crashes. Notably, in the contiguous U.S. (i.e., the lower 48 states) numerous stocks of salmon have been severely depleted or entirely extirpated due to human activities. Where these downturns have occurred, remaining stocks are left considerably more vulnerable to fishing pressure. The comparatively pristine freshwater systems in Alaska have left salmon runs there comparatively resilient to fishing pressure. Stock Status As a result of habitat loss, climatic shifts, historic overfishing, and other factors, the abundance of many populations of salmon has declined substantially over the past century. Overall, Chinook, coho, sockeye, and pink salmon stocks in California, Oregon, and Washington have been significantly depleted from peak abundances, although fishing is not considered one of the primary causes of the declines in many cases. In Washington, several large runs continue to be viable. In several cases, long-term declines in abundance have been halted or reversed in the recent past. The health of Washington stocks are considered a moderate conservation concern because abundances and trends vary in space and time, with targeted stocks depleted from historical levels of abundance, but generally meeting conservation goals. However, a major run supporting both California and Oregon fisheries (Sacramento River Fall Chinook, or SRFC) was recently at record low abundance and failed to meet minimum escapement goals for three consecutive years, triggering a formal Overfishing Concern. Escapement improved in 2010 to a level just over the minimum annual escapement goal. As the stock met conservation objectives in 2010, the stock status of salmon landed in California and Oregon is considered a moderate conservation concern. In contrast, Alaskan salmon, augmented by large hatchery operations, appear to be in robust health, with record abundance and harvests over the past two decades. The status of Alaska salmon stocks is therefore a low conservation concern. Bycatch The gear employed in commercial salmon fisheries includes drift and set gillnets, purse seines, and trolling gear (also referred to as hook-and-line gear). When combined with management constraints such as area closures and gear restrictions, the methods used to catch salmon are highly selective for salmon, and overall bycatch rates appear low in all salmon fisheries. However, one of the inherent difficulties of managing salmon is that they are captured in mixed- stock fisheries, in which salmon from a variety of different areas may be caught in the same nets or on the same hooks. This poses a particularly difficult problem in California and the Pacific Northwest where nearly thirty salmon and steelhead Evolutionarily Significant Units (ESUs) Seafood Watch® Wild Pacific Salmon Report April 25, 2011 have been listed as Threatened or Endangered under the Endangered Species Act. Regular landings of these fish remains a serious concern despite management efforts to reduce exploitation rates. In Alaska, the relative health of salmon stocks and low bycatch rates of endangered and threatened stocks from the Pacific Northwest has reduced the seriousness of the bycatch issue for most Alaska fisheries, although bycatch of ESA listed stocks remains a concern in southeast Alaska troll fisheries. Habitat Effects The gear types used in salmon fisheries (drift gillnets, purse seines, and trolling gear) rarely touch the sea floor. As such, salmon fisheries have little lasting physical impact on aquatic habitats. However, the salmon fishery system can indirectly affect aquatic habitats. Most notably, the widespread use of salmon hatcheries for conservation and fisheries augmentation purposes has, in many cases, significantly degraded the natural habitat of wild salmonids. Hatcheries have often been poorly integrated with wild runs, and can jeopardize their health especially in areas where wild salmon populations are depleted. The effects of salmon hatcheries on the health of wild salmon stocks has been empirically demonstrated in California and the Pacific Northwest, and important questions about Alaskan hatcheries remain unanswered. Management Managers of U.S. West Coast salmon fisheries assess stocks on a timely basis, typically issuing preseason abundance forecasts and updating regulations as the season progresses. Managers regularly assess fisheries-dependent data, such as landings, and fisheries-independent data, such as run size, ocean conditions, and fish age, to determine stock status and fishing levels. Management does not have a track record of setting catch quotas over what its scientific advisors have recommended. Managers require specific gear types and employ closed areas to reduce wasteful discards, and actively craft fishing seasons and regulations to reduce harmful impacts on endangered or struggling stocks. However, the effectiveness of the bycatch reduction measures is not clear, as bycatch