Tilapia United States
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Tilapia Nile tilapia (Oreochromis niloticus), Blue tilapia (Oreochromis aureus), Mozambique tilapia (Oreochromis mossambicus), and Hybrid tilapia (Oreochromis spp.) (© Monterey Bay Aquarium) United States Closed recirculating systems 5/23/2012 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 the US presents a final high overall score of 8.84, and therefore is ranked Best Choice overall. Tilapia Oreochromis niloticus, O. mossambicus, O. aureus, O. spp. USA Closed recirculating systems Criterion Score (0-10) Rank Critical? C1 Data 5.75 YELLOW N/A C2 Effluent 9.00 GREEN NO C3 Habitat 7.87 GREEN NO C4 Chemicals 10.00 GREEN NO C5 Feed 8.10 GREEN NO C6 Escapes 10.00 GREEN NO C7 Disease 10.00 GREEN 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 70.72 Final score 8.84 OVERALL RANKING Final Score 8.84 Initial rank GREEN Red criteria 0 Interim rank GREEN Critical Criteria? NO Final Rank BEST CHOICE Scoring note – scores range from zero to ten where zero indicates very poor performance and ten indicates the aquaculture operations have no significant impact. 3 Executive Summary U.S. Tilapia markets are dominated by imports as less than 5% of consumed tilapia is produced domestically. Tilapia production in the U.S. is mostly performed in the southern states, and more than 75% of the annual production is supplied by recirculating systems. Statistics on tilapia production in the US are often aggregated and not always updated. Even though research is performed by several institutions (e.g. US Department of Agriculture (USDA), universities) and results are published in peer-reviewed journals, information on current management practices and their associated impacts in tilapia production in the US are not always available. For instance, information on effluents, impacts on habitat, wildlife mortalities and feeds is scarce. Therefore, data quality and availability is considered to be moderate. The relative low wastes produced by US tilapia farms per ton of harvested fish (38.4 kg N) are treated in the same facility, disposed in external treatment plants or used to irrigate agricultural crops. The combination of appropriate effluent treatments, which determine that wastes are not directly released to a receiving water body, and strong regulations controlling waste discharge at regional levels results in the highest score for the effluent criterion. Most of US tilapia production is performed in recirculating systems located in the arid west and in the Northeast, involving minor risks in terms of ecosystem services. Regulations and enforcement controlling farm siting and licensing are considered to be moderate as an Environmental Impact Assessment is only required in a few states. The combination of the high score for habitat conversion and function, and the moderate score for regulatory or management effectiveness results in a relative high overall score for the habitat criterion. Although aquaculture operations can directly or indirectly cause the death of predators or other wildlife, most tilapia farms in the US are indoor facilities or ponds covered by greenhouse roofs, and isolated from wildlife and predators. In the case of outdoor ponds, non-lethal methods are used to frighten wild animals such as waterbirds. Therefore, it is considered that tilapia farms present no negative impacts in terms of wildlife and predators mortalities. Tilapia production in the US does not involve a frequent use of chemicals. Only eight drugs are fully approved for use in US aquaculture, and these are mostly used to treat or prevent diseases. Other chemicals, such as methyltestosterone used for sex reversal, can only be used with a special permit in hatcheries, which are closed systems. The low chemical use in tilapia production in the US determines a high score for this criterion. Tilapia feeds have a low inclusion level of marine ingredients (fishmeal and fish oil), moderate protein levels (around 30%), and are dominated by crop-derived ingredients. Furthermore, the Feed Conversion Ratio is around 1.4, (i.e. 1.4 pounds of feed are required to get a pound of fish). These characteristics determine a low Fish In: Fish Out (FIFO) ratio (0.42), a negative balance of protein as a result of tilapia production (35.8% of protein in inputs is lost), and a low 4 feed footprint (1.08 hectares). The combination of these partial factors results in a high score for the feed criterion. Tilapia is a highly successful invasive species in temperate and subtropical aquatic environments. It was introduced during the 1960s to the US and there are some established populations in the wild. However, the risk of escape in US tilapia farms is very low. Tilapia production in the US is fully independent from international live animal shipments and from wild sources of stock as well. One hundred percent of tilapia stock is produced in 28 hatcheries across the US. US tilapia farms are characterized by high stocking densities and water reuse. These might lead to high stress level in fish that favors the amplification of pathogens and parasites. Bacterial diseases such as Streptococcus or Vibrio have been reported in tilapia operations. However, tilapia operations are closed facilities. As tilapia farms are not connected to wild populations, it is considered that they do not involve any risk of retransmission of pathogens or parasites to wild populations. Tilapia from the US presents a final high overall score of 8.84, and therefore is ranked Green or “Best Choice” overall. 5 Table of Contents Final Seafood Recommendation ..................................................................................................... 2 Executive Summary ......................................................................................................................... 3 Introduction .................................................................................................................................... 6 Scope of the analysis and ensuing recommendation ............................................................ 6 Analysis ........................................................................................................................................... 8 Scoring guide .......................................................................................................................... 8 Criterion 1: Data quality and availability ............................................................................... 9 Criterion 2: Effluents ............................................................................................................ 11 Criterion 3: Habitat .............................................................................................................. 14 Criterion 3.3X: Wildlife and predator mortalities ................................................................ 16 Criterion 4: Evidence or Risk of Chemical Use ..................................................................... 17 Criterion 5: Feed .................................................................................................................. 18 Criterion 6: Escapes ............................................................................................................. 20 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 ....................................... 25 Overall Recommendation ............................................................................................................. 26 Acknowledgements ....................................................................................................................... 27 References .................................................................................................................................... 27 About Seafood Watch® ................................................................................................................. 34 Guiding Principles ......................................................................................................................... 35 Data points and all scoring calculations........................................................................................ 37 6 Introduction Scope of the analysis and ensuing recommendation - Species: Nile tilapia (Oreochromis niloticus), Blue tilapia (O. aureus), Mozambique tilapia (O.mossambicus), and hybrid tilapia (O. spp.). - Geographic coverage: USA - Production Methods: Closed recirculating systems Species Overview