Seafood Watch Seafood Report
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Seafood Watch Seafood Report Farmed Tilapia Oreochromis, Sarotherodon, Tilapia Image © Monterey Bay Aquarium Final Report May 16, 2006 Appendix I & II December 23, 2009 Irene Tetreault Independent Consultant Seafood Watch® Farmed Tilapia Report May 16, 2006 About Seafood Watch® and the Seafood Reports 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 the Internet (seafoodwatch.org) or obtained from the Seafood Watch® program by emailing [email protected]. 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® Fisheries 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. 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. Seafood Watch® and Seafood Reports are made possible through a grant from the David and Lucile Packard Foundation. 1 Seafood Watch® Farmed Tilapia Report May 16, 2006 Table of Contents Executive Summary........................................................................................................................ 3 Introduction..................................................................................................................................... 7 Availability of Science.............................................................................................................. 15 Market Availability................................................................................................................... 16 Analysis of Seafood Watch® Sustainability Criteria for Wild-caught Species ........................... 17 Criterion 1: Use of Marine Resources ...................................................................................... 17 Criterion 2: Risk of Escaped Fish to Wild Stocks .................................................................... 21 Criterion 3: Risk of Disease and Parasite Transfer to Ecosystem ........................................... 25 Criterion 4: Risk of Pollution and Habitat Effects................................................................... 26 Criterion 5: Effectiveness of the Management Regime........................................................... 29 Overall Evaluation and Seafood Recommendation ...................................................................... 33 Acknowledgements....................................................................................................................... 36 References..................................................................................................................................... 37 Appendices.................................................................................................................................... 39 Appendix I. Assessment of Elite Aquaculture Ltd Farmed Tilapia.......................................... 39 Appendix II. Aquaculture Evaluation of Elite Aquaculture Ltd Farmed Tilapia ..................... 55 2 Seafood Watch® Farmed Tilapia Report May 16, 2006 Executive Summary Tilapia are the most widely grown of any farmed fish. They are highly adaptable and easily cultured. Tilapia are second only to carp as the most important farmed fish in the world. The most commonly farmed tilapia species on the U.S. market are Nile, Mozambique, and blue. Farmed tilapia far outweigh the importance of wild-caught tilapia. Farming methods are diverse and imports dominate the U.S. tilapia market. China and Taiwan lead global aquaculture production in tilapia and are the source of 56% and 20%, respectively, of the frozen tilapia imported to the U.S. in 2005. Imports of fresh tilapia fillets on the other hand are usually from Ecuador, Honduras, or Costa Rica. Culture of tilapia can be categorized by method and system. Methods, ranging generally from low to high sustainability, include extensive culture, polyculture, and culture integrated with agriculture. Among the least sustainable methods are semi-intensive and intensive culture, but the relative order of sustainability between these two methods is arguable. In production, nets and pens are submerged in reservoirs, lakes, and other open bodies of water, and open to the environment. Flow-through raceways are open and flushed by streams. Ponds and recirculating tanks are relatively closed systems depending on how often water is exchanged with the environment. Commercial farms using closed systems are usually more sustainable, and farms integrated with agriculture are preferable. The combination of semi-intensive or intensive methods and an open system usually results in high environmental risk. Because production is rapidly expanding and ecological issues are still emerging, it is necessary to take a precautionary approach in rating the sustainability of farmed tilapia. Seafood Watch® has attempted to generalize by country for the benefit of consumers, as well as by production process for retailers and businesses, who can verify production methods. However, sustainability varies greatly at the level of individual farms, thus this report is not necessarily comprehensive. Certification for individual farms is vital. Below is a summary of findings based on five criteria for sustainability: 1) use of marine resources; 2) risk of escapes; 3) risk of disease transfer; 4) habitat and pollution risk; and 5) management effectiveness. Energy inputs and water and land use are not considered here. 1) Use of marine resources is measured as the ratio of wild-caught fish input to farmed fish output. A net producer of aquatic protein has a ratio less than 1:1. For tilapia, recent estimates ranged from 0.27 to 1.41, with the vast majority falling below 1:1. This indicates that tilapia farming in general is a net producer of fish protein. 2) Introduced tilapia have caused significant adverse impacts. They easily invade new habitat and are probably the most widely distributed exotic fish in the world. Escapes are possible from ponds and tanks, but open systems such as nets, pens, and raceways in particular inevitably allow escapes and pose a high risk. Risk is low only for farms without access to natural waters. 3) Tilapia are relatively resistant to disease. For organic product and farms using ponds and tanks risk is likely low, but net, pen, and raceway run a higher risk of disease transfer, meriting caution. 4) Tilapia pose some risk to vulnerable habitats, and pollution risks from effluent can be high. Fish stocked in high densities and fed supplemental feeds increase the risk of pollution. Nets and cages also increase the risk of pollution because waste cannot be managed or treated. Central America continues to intensify 3 Seafood Watch® Farmed Tilapia Report May 16, 2006 and to favor open systems, thus conservation concern there is moderate for pollution impacts. There is also moderate concern for pollution impacts for organic-certified farms until effective control is more clearly demonstrated. Pollution concern is low for U.S. product due to comprehensive effluent regulations. 5) There appears to be a general lack of comprehensive management outside the U.S. Organic certification offers an additional layer of management for individual farms, but China’s rapid increase in intensification, coupled