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Tilapia Oreochromis niloticus, O. niloticus x O. aureus, Oreochromis spp. (© Monterey Bay Aquarium) China Ponds 6/1/2012 Ariel Zajdband, Seafood Watch Disclaimer Seafood Watch® strives to ensure all our Seafood Reports and the recommendations contained therein are accurate and reflect the most up-to-date evidence available at time of publication. All our reports are peer- reviewed for accuracy and completeness by external scientists with expertise in ecology, fisheries science or 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. We always welcome additional or updated data that can be used for the next revision. Seafood Watch and Seafood Reports are made possible through a grant from the David and Lucile Packard Foundation. 2 Final Seafood Recommendation Tilapia from China received one red ranking—chemical use (the Data criterion does not contribute to the number of red criteria) and a moderate final score (5.34). Therefore, Chinese tilapia is ranked a Good Alternative overall. Tilapia O. niloticus, O. niloticus x O. aureus, Oreochromis spp. China Ponds Criterion Score (0-10) Rank Critical? C1 Data 2.50 RED1 N/A C2 Effluent 6.00 YELLOW NO C3 Habitat 4.82 YELLOW NO C4 Chemicals 0.00 RED NO C5 Feed 9.39 GREEN NO C6 Escapes 5.00 YELLOW NO C7 Disease 5.00 YELLOW NO C8 Source 10.00 GREEN N/A 3.3X Wildlife mortalities 0.00 GREEN NO 6.2X Introduced species escape 0.00 GREEN N/A Total 42.71 Final score 5.34 OVERALL RANKING Final Score 5.34 Initial Rank YELLOW Red Criteria 1 Interim Rank YELLOW Critical Criteria? NO Final Rank GOOD ALTERNATIVE Scoring note – scores range from zero to ten where zero indicates very poor performance and ten indicates the aquaculture operations have no significant impact. 1 The data criterion does not contribute to the number of “Red” criteria in terms of determining the final rank. 3 Executive Summary China is the world’s largest producer of farmed tilapia, harvesting 1.2 million tons in 2010, and supplying approximately 40% of global production. Nearly 40% of China’s production is exported to the United States, mainly as frozen fillets. Production is predominantly in ponds that usually discharge water only once per cycle (at harvest). Despite its size and high importance to the US market, robust environmental monitoring statistics from China are not available, and most information on tilapia production is dispersed, and only available in Chinese. Data availability is therefore considered poor. Although tilapia can be grown with minimal feed inputs or waste production in low intensity systems, production for export typically operates with a higher intensity of feed inputs and waste (effluent) outputs. The level of N wastes (29.44 kg N) produced per ton of harvested fish is considered relatively low, and only about a quarter of these wastes are directly released to the environment from the ponds. However, there are no specificities in China’s effluent regulations that relate to the cumulative impacts of multiple farms, and enforcement by local authorities appears almost nonexistent. The farms are considered to have moderate impacts on the habitat’s provision of ecosystem services and they are located in low-value environments, but regulations and enforcement regarding licensing and site selection are weak. Tilapia can be raised successfully on vegetable-based feeds, but production for export markets typically uses some fishmeal to increase growth rates. However, the low level of marine ingredients and the relatively high inclusion of crop ingredients in feed result in low values for both wild fish use and the feed footprint. Tilapia production results in a net protein gain as a result of the relatively low Feed Conversion Ratio (FCR~1.3) and protein level in the diet, and the inclusion of 28% of the protein from non-edible sources. The risk of escape is considered to be moderate-low in ponds with low water exchange and tilapia is a highly invasive species, but populations are already well established in the wild. In these circumstances, the potential impacts of escaping tilapia are considered to be relatively moderate. Although historically considered to be relatively resilient to disease, the increasing intensification of tilapia production means that disease-related mortalities are now frequent. Farms discharge water without relevant treatment implying a risk of disease transfer from the farms to wild fish, and banned or illegal chemicals such as antibiotics and fungal treatments (nitrofurans and malachite green) are still used in tilapia production in China. 100% of tilapia fingerlings in China are produced in hatcheries, so the industry is considered to be independent of wild fisheries with respect to supplying broodstook and fingerlings for production. 4 Overall, Chinese tilapia gets a moderate overall score of 5.34 out of ten. Tilapia as a species has the potential to be raised in sustainable ways, but the increasing intensification and industrialization has resulted in one “Red” score for the Chemical Use criterion. This means that the overall ranking is “Yellow”, and therefore the recommendation is “Good Alternative”. 5 Table of Contents Final Seafood Recommendation ..................................................................................................... 2 Executive Summary................................................................................................................ 3 Table of Contents ................................................................................................................... 5 Introduction .................................................................................................................................... 6 Analysis ........................................................................................................................................... 7 Scoring guide .......................................................................................................................... 7 Criterion 1: Data quality and availability ............................................................................... 8 Criterion 2: Effluents ............................................................................................................ 10 Criterion 3: Habitat .............................................................................................................. 13 Criterion 3.3X: Wildlife and predator mortalities ................................................................ 15 Criterion 4: Evidence or Risk of Chemical Use ..................................................................... 16 Criterion 5: Feed .................................................................................................................. 18 Criterion 6: Escapes ............................................................................................................. 21 Criterion 6.2X: Escape of unintentionally introduced species ............................................. 22 Criterion 7. Disease; pathogen and parasite interactions ................................................... 23 Criterion 8. Source of Stock – independence from wild fisheries ....................................... 24 Overall Recommendation ............................................................................................................. 25 Acknowledgements ....................................................................................................................... 26 References .................................................................................................................................... 26 About Seafood Watch® ................................................................................................................. 33 Guiding Principles ......................................................................................................................... 34 Data points and all scoring calculations........................................................................................ 36 Appendix I. Assessment of Elite Aquaculture Ltd Farmed Tilapia ................................................ 43 Appendix II. Aquaculture Evaluation of Elite Aquaculture Ltd Farmed Tilapia ............................ 61 6 Introduction Scope of the analysis and ensuing recommendation This report focuses on pond raised Nile tilapia (Oreochromis niloticus) from Mainland China. This report does not assess production from Taiwan. Farmed tilapias in China are Nile tilapia (Oreochromis niloticus), hybrids between O. niloticus females and blue tilapia (O. aureus) males, and red tilapia (O. spp.). Genetically improved Nile tilapia, such as the GIFT and the GST strains2, were imported and adopted by Chinese farmers due to its faster growth (Eknath et al. 2007, Fu et al. 2008). The hybrids produced by crossing Nile tilapia and Blue tilapia are preferred by some farmers because of its high male percentage and better survival at low temperatures. Red tilapia (Oreochromis spp.) is grown in brackish water environments due to their higher salinity tolerance (Thodesen et al. 2011, Zhao et al. 2011). In the statistics all production is reported as Nile tilapia (FAO 2009). Species overview Tilapia is a prolific fast-growing tropical species, native to Africa and the Middle East, but introduced elsewhere as a valuable food fish.