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 with ineffective management, is of particular concern. Caution is warranted for management in other countries as intensification continues.
For consumers, Seafood Watch® suggest avoiding farmed tilapia from China and Taiwan. Seafood Watch® recommends organic certified (e.g., NaturLand) and U.S. grown tilapia product as a Best Choice, while tilapia from other countries including Central America are recommended as Good Alternatives. For retailers and those able to verify production methods, Seafood Watch® recommends product (regardless of country of origin) from farms integrated with agriculture and with no access to natural waters; Seafood Watch® considers farms using semi- intensive and intensive methods in enclosed ponds and tanks as good alternatives, and suggests avoiding tilapia from farms using semi-intensive and intensive methods in pens, cages, and raceways.
These conclusions are preliminary and reflect the difficulty in evaluating the sustainability of the rapidly changing and complicated worldwide tilapia farming industry. As farming practices and data change, Seafood Watch reserves the right, in its sole and absolute discretion, to review, revise, or amend the contents of this report and associated recommendations at any time to reflect this new information.
April 2010 This report has been amended by the addition (Appendix I and II) of a farm-level assessment of Elite Aquaculture Co Ltd – a company producing farmed tilapia in southeast China. In contrast to the overall Seafood Watch Farmed Tilapia report which covers China on a country-wide basis, this is a farm-specific report on Elite Aquaculture Co Ltd (Elite) in southeast China, compiled as part of pilot project for the Seafood Watch Major Buyer partnership program. See Appendix 1 for more details. The rest of the existing report was not modified.
4 Seafood Watch® Farmed Tilapia Report May 16, 2006
Table of Sustainability Ranks
For the consumer, by country.
Conservation Concern Sustainability Criteria Low Moderate High Critical Use of Marine Resources √ All Risk of Escapes to Wild Stocks √ US, Organic √ Other Risk of Disease/Parasite Transfer to Ecosystem √ US, Organic √ Other Risk of Pollution and √ Organic, √ US Habitat Effects Other
Effectiveness of Management √ US, Organic √ Other √ China
Overall Seafood Recommendation:
U.S., Organic Best Choices Good Alternatives Avoid
Other Best Choices Good Alternatives Avoid (Ecuador, Brazil, Honduras, Costa Rica)
China, Taiwan Best Choices Good Alternatives Avoid
5 Seafood Watch® Farmed Tilapia Report May 16, 2006
For the retailer, by production system and method (see pages 8-9 for definitions).
Conservation Concern Sustainability Criteria Low Moderate High Critical Use of Marine All Resources Nets, Cages, & Risk of Escapes to No Access to Enclosed Ponds Raceways, Wild Stocks Natural Waters & Tanks Unenclosed Ponds & Tanks Nets, Cages & Risk of Disease/ Enclosed Ponds Raceways, Parasite Transfer to & Tanks Unenclosed Ecosystem Ponds & Tanks All Ponds & Risk of Pollution and Nets, Cages & Integrated Recirculating Habitat Effects Raceways Tanks Effectiveness of Not Applicable Management
Overall Seafood Recommendation:
Integrated + No Access to Natural Waters Best Choices Good Alternatives Avoid
Semi-intense or Intensive + Enclosed Ponds Or Tanks Best Choices Good Alternatives Avoid
Semi-intense or Intensive + Nets, Cages & Raceways Or Unenclosed Ponds Or Tanks Best Choices Good Alternatives Avoid
6 Seafood Watch® Farmed Tilapia Report May 16, 2006
Introduction
World production from wild capture fisheries has plateaued amid a backdrop of increasing world population and demand for fish products. Aquaculture has been viewed as the “blue revolution” that will meet increasing demand in a sustainable fashion. However, there is controversy regarding the sustainability of aquaculture based on concerns regarding aquafeeds, impacts to wild stocks from farm escapes, and pollution and eutrophication associated with excess nutrient waste, as well as transmission of parasites and disease to wild and farmed populations. Tilapia aquaculture in particular is growing rapidly, and ecological impacts are still emerging.
“Tilapia” is the common name for many cichlid species within three genera: Oreochromis, Sarotherodon, and Tilapia (Watanabe et al. 2002). The species of greatest importance to aquaculture are the Nile tilapia (Oreochromis niloticus), Mozambique tilapia (O. mossambicus), and blue tilapia (O. aureus) and their hybrids (Martins et al. 2004). According to the United Nations Food and Agriculture Organization (FAO) Fishery Statistics data from 2003, 82% of cultured tilapia are Nile tilapia (Figure 1).
Blue (0.1%) Other (15%)
Nile (82%)
Mozambique (3%)
Figure 1. Percentage of global tilapia aquaculture production by species (data from FAO 2003).
Basic biology Tilapia are easily cultured because they are omnivorous and can adapt their eating habits to available food. In addition, they can tolerate low oxygen levels and a wide range of salinities and can be farmed within a wide range of densities. They also have high reproductive capacity and readily establish self-reproducing populations. Tilapia occur mainly in freshwater but also in brackish water and seawater in tropical and subtropical climates. They occupy a wide variety of habitats like rivers, lakes, sewage canals and irrigation channels. Tilapia feed mainly on phytoplankton or benthic algae but readily accept compound feed (with plant or animal protein). For tilapia, spawning occurs year-round and juveniles mature as early as six months. According to FishBase (2005), maximum recorded life history parameters for Nile tilapia are 60 cm standard length (SL), 4.3 kg weight, and 9 years of age. Males grow faster than females, mainly because females begin reproducing early and thus divert their energy to reproduction instead of growth. There are several methods used to avoid loss of marketable biomass through excess reproduction. Farming in cages does not allow females to pick up eggs for oral incubation,
7 Seafood Watch® Farmed Tilapia Report May 16, 2006 which eliminates reproduction. Culture populations that are exclusively male are also often desirable to control reproduction and maximize biomass production. Typically, all-male populations are created by treating fry with methyl testosterone to cause sex reversal, which may compromise worker and consumer health. Sorting fingerlings to separate the sexes by hand is best for consumer and farm worker health, but is labor intensive. Alternatively, farmers use YY males as brood stock, a form of genetic manipulation, to create Genetically Modified Tilapia (GMT). GMT does not produce a Genetically Modified Organism, but may be excluded from organic certification. GMT begins with hormone treatment to produce fingerling males (XY) which develop into adults that function as females (Figure 2). These XY females are mated with normal XY males. One quarter of their offspring will be YY males. In culture the YY males can be mated with normal XX females and all their offspring will be male (XY).
Figure 2. Methodology for culturing all-male tilapia populations (from Subasinghe et al. 2003).
Native, wild, and introduced populations Tilapia are native to Africa and the Middle East, but have established populations throughout the world. Approximately 85 counties farm tilapia and about 98% of all farmed product is grown outside its native habitat (Gupta and Acosta 2004).
8 Seafood Watch® Farmed Tilapia Report May 16, 2006
Aquaculture vs. capture fisheries Tilapia farms produce much more commercial product than wild tilapia capture fisheries. Since 1990, global aquaculture production has been expanding exponentially and currently exceeds 1.2 million metric tons (Figure 3). In contrast, capture from the wild began increasing in 1990 but leveled off near 250,000 metric tons in the early 2000s.
Figure 3. Global tilapia production from aquaculture (left) and capture fisheries (right). Data from FAO 2002. NOTE: different y-axes.
Aquaculture history and current status Tilapia has been farmed for food throughout human history, as seen around 2000-2500 BC in ancient Egypt (El-Sayed 1999). The first scientific culture was recorded in 1924 in Kenya, followed by introduction throughout Africa. In the late 1940’s tilapia were introduced in the Far East for farming and then in America in the 1950’s (Gupta and Acosta 2004).
China 900,000 Egypt 800,000 Philippines 700,000 Indonesia Thailand 600,000 Taiwan 500,000 Brazil
400,000 Lao Colombia 300,000 Malaysia 200,000 Costa Rica Ecuador 100,000 USA 0 Mexico 2000 2001 2002 2003 Israel
Figure 4. Global tilapia aquaculture production (mt) by top 15 producing countries (data from FAO 2003).
9 Seafood Watch® Farmed Tilapia Report May 16, 2006
Tilapia farming has expanded so much in the past 30 years that tilapia is now the second most important farmed fish in the world (the first most important being carp). This continued expansion hails tilapia as the most important aquaculture species of the 21st century (see Gupta and Acosta 2004 and references therein). China currently dominates tilapia aquaculture (Figure 4), while expansion continues in the Caribbean, Latin America, and temperate regions, which use artificially heated water. Temperate farms exist in the United States, but constitute only 0.5% of global tilapia aquaculture. Sources to the U.S. market can be found in Table 2 on page 14 of this report.
Aquaculture methods and systems Most farmed tilapia (85%) are cultured in freshwater (FAO 2002, cited in Gupta and Acosta 2004), while 14.1% are cultured in brackish water, and even a few species are cultured in seawater. Aquaculture methods vary, from extensive farming to semi-intensive to intensive, as do the types of production systems used (e.g., cages, ponds, raceways, tanks). (See Figure 5on page 9 of this report for an overview of these methods and systems.) Each tilapia farm has its own environmental implications that are a result of the method and system used, but in general increased intensification uses more natural resources and causes greater environmental degradation. Choo (2001) briefly describes the major tilapia culture methods, below:
Culture methods Extensive culture Extensive culture is the historical culture method that compliments natural conditions, with fish relying only on natural food. This method continues today in subsistence farming, but is not viable to feed the modern world’s growing population (Choo 2001).
Polyculture Polyculture is the production of a mixed crop of fish, using basic principles of ecology to more fully utilize resources. One example of tilapia polyculture is a pond that stocks shrimp along with tilapia. In this polyculture, shrimp effluents fertilize tilapia ponds and tilapia reduce the parasites that infest shrimp. Although this practice is sometimes referred to as “integrated,” for this report we use the term polyculture, as integrated will refer to agriculture-aquaculture integration (below).
Integrated culture Integrated agriculture-aquaculture (IAA) farming utilizes waste as a resource, resulting in the recycling of nutrients and organic wastes. Fish ponds are fertilized with agricultural wastewater, which reduces the runoff of excess nutrients to the environment while improving the growth of aquatic plants that can feed the herbivorous tilapia, and mud from ponds is used to fertilize crops. Of the culture systems described later in this section, ponds, tanks, and raceways can be integrated into agricultural systems, resulting in higher sustainability. On the other hand, untreated discharge from the same ponds, tanks, and raceways can be a concern in terms of pollution, fish escapes, and disease transmission to wild fish stocks.
Semi-intensive and intensive culture Semi-intensive methods require some feed and fertilizer input, while intensive methods rely heavily on formulated feeds (“complete feeds”). The result of using this formulated feeds is
10 Seafood Watch® Farmed Tilapia Report May 16, 2006
often a large amount of uneaten feed, which can range from 1-30% of the total amount of formulated feed used, depending on the culture system, the type of feed, and management of the system, as well as on species and type of feed. Discharge of effluents into adjacent ponds or used for irrigation is relatively benign, but direct discharge of effluents with these uneaten feeds into rivers can be detrimental to stream health. Increasing intensity of the culture system causes more nitrogen and phosphorus pollution due to increased excess feed and resulting wastes.
Culture systems The following paragraphs describe commonly used culture systems throughout the world (see Gupta and Acosta 2004 and Boyd et al. 2005). Cages and nets are used in water-based systems, while ponds, raceways and tanks are used in land-based systems.
Nets, cages (open) Cages and nets are submerged within lakes, reservoirs, rivers, streams, irrigation systems, wells, or estuaries and are open to the surrounding waters. Nets allow fish access to the bottom of the water body, while cages do not. Cages can range from 1-2 m3 up to 1,000 m3 or more.
Ponds (closed) Ponds are a common system used to grow-out tilapia to market size. They are not as open as nets and cages, but can still be compromised by storms that connect ponds to local water bodies. Ponds can have surface areas varying from hundreds of square meters to tens of hectares, and are usually 1 to 2 m deep. In China, Taiwan, Thailand, and the Philippines most farmers fertilize ponds and use formulated feeds, which are considered semi-intensive to intensive.
Flow-through raceways (open) and recirculating tanks (closed) Tanks and raceways are land-based. They are artificial ponds but lack important biological aspects of ponds, thus they require a continuous flow of water. The terms “tank” and “raceway” are sometimes used interchangeably. For this report, “raceway” refers to an artificial structure that uses flow-through water. Flow-through systems are open and use large quantities of water (they are constantly supplied with fresh water, which is used and then discharged). “Tank” refers to a structure using recirculating water. Recirculating systems recycle more than 90% of the system’s water volume (Waller 2001 and references cited therein); thus, tanks are less open, but when discharged effluent can be highly concentrated. Discharge from both flow-through raceways and recirculating tanks can be treated to mitigate environmental impacts. Unless enclosed within a structure, both tanks and raceways can be compromised by weather events.
11 Seafood Watch® Farmed Tilapia Report May 16, 2006
Figure 5. Farming systems and methods, and feed management options and their yields (from Tacon 1996, modified after Edwards 1993).
Tanks and raceways are expensive but allow great control over the culture environment (light, temperature, fish density, swimming activity, etc.). Addition of heat permits tilapia farming in temperate regions such as the U.S.
Environmental impacts of aquaculture Figure 5 illustrates the relationship between yield (metric tons produced per hectare per year) and combinations of farming methods and systems. Increasing intensification generates higher yields, but can generate more negative environmental impacts.
Historically, environmental impacts from aquaculture were generally considered low because practices were usually extensive (low inputs, low fish density, low outputs). Only recently have semi-intensive or intensive methods (high inputs, high fish density, high outputs) become widespread. Especially controversial is the culture of shrimp in the tropics, where they are often kept in ponds within sensitive mangrove habitat (Choo 2001), and carnivorous species, such as salmon, which are heavily dependent on fishmeal and fish oil feeds and are also kept in net and cage systems in coastal marine waters.
Contrary to salmon, tilapia is omnivorous; thus its farming may not be as controversial. Due to its omnivory, historically, farmed tilapia required few or no additions to the aquaculture system, and thus it has generally been regarded as sustainable. Today, however, the sustainability of commercial tilapia increasingly depends on the intensity of the culture method employed, and on whether or not the system is closed to the surrounding environment (increasing production intensity in combination with an open system results in decreasing sustainability).
With regard to human impacts, the concept of “sustainability” includes not only direct effects on the immediate physical environment (e.g., wastes and by-products) but also the effects on resources used by that activity, which may be remote from the culture site. For example,
12 Seafood Watch® Farmed Tilapia Report May 16, 2006
fishmeal and fish oil used to feed cultured fish often originate from small pelagic fish taken in wild capture fisheries that are distant from the culture location. While tilapia is omnivorous, and thus historically has not required such additional feeds, increased farm intensity has resulted in the use of fishmeal and fish oil in feeds for tilapia culture, creating an impact on these wild capture fisheries.
The use of wild fish to supplement aquaculture plays into the concept of an ecological footprint (Kautsky et al. 1997), which has been used to describe the overall ecological impact of tilapia and other aquaculture farms and illustrates some of the differences in sustainability between various culture systems and methods. An ecological footprint is an estimate of the ecosystem support area required to sustain the natural resources and ecosystem functions necessary to produce the “crop” in the area being cultured. Natural resources include water and food inputs, while ecosystem functions include the processing of wastes (nutrient assimilation) and oxygen production. As one example, there are tilapia farms using intensive methods and open systems in Lake Kariba in Zimbabwe. Kautsky et al. (1997) estimates their ecological footprint to be an area 10,000 times the size of the cage to produce natural resources and 115-275 times the cage size for waste assimilation. The authors contrast this with a farm using semi-intensive methods in a closed pond, which is much more sustainable, with an ecological footprint only as large as the size of the pond itself (i.e., 1:1 footprint per area of activity). However, beyond waste assimilation there are other important factors to consider for tilapia culture, particularly the issue of escaped fish, which is not adequately addressed through the concept of an ecological footprint.
Certification standards for aquaculture With the growing concern over aquaculture practices, there is a movement toward certification of sustainable, natural, and organic aquaculture products from governmental and non-governmental agencies. For example see the Marine Stewardship Council at http://www.msc.org/ for certified capture fisheries and product sources. A recent article by Boyd et al. (2005) details environmental issues and certification concerns for several aquaculture products, including tilapia. Their table, reproduced below, summarizes priority issues according to species.
13 Seafood Watch® Farmed Tilapia Report May 16, 2006
Table 1. Relative importance of issues relevant to certification of aquaculture species or species groups (L = low; M = medium; H = high). From Boyd et al. (2005).
Experts predict that the forthcoming USDA organic certification will become the industry standard. The USDA’s National Organic Program staff and National Organic Standards Board (NOSB) members are reviewing guidelines for both farmed and wild-caught fish. The NOSB created the Aquatic Animal Task Force in 2000, and in 2005 formed two working groups—one for wild and one for farmed animals—to recommend organic certification requirements. A draft report of recommendations was released in February 2006 but as of yet no standards have been formally established in the U.S. In the absence of a U.S. organic label, the wide range of international organic certification labels seen in the market may cause confusion.
Europe has a number of organic certification organizations. NaturLand of Germany is a major organic certifier, which has been recognized by the International Federation of Organic Agriculture Movements (IFOAM) since 1997. NaturLand’s first standards for aquaculture were established in 1995 for pond farming. Brazil’s 8th Sea tilapia (www.8thsea.net) is certified organic by NaturLand, based on general aquaculture standards. Standards specifically for tilapia are forthcoming.
Seafood Watch’s review of NaturLand's general aquaculture standards for organic certification show that they cover all five criteria evaluated by Seafood Watch® in this report, as well as other considerations (NaturLand, personal communication). NaturLand encourages polyculture and integrated agriculture and encourages minimal use of fishmeal and fish oil. For certification, water quality and stocking density must conform to the species’ natural environment, and effective preventative measures are expected to be the primary method of controlling disease and parasitic infections. Natural curative substances (e.g., salt) are preferred to chemical or synthetic substances, and dead organisms must be removed from the holding system immediately. Synthetic antibiotics, growth-enhancers, and feed supplements are prohibited. Effluent must not adversely affect the surrounding ecosystems, and introduction of non-native species must be prevented, while eggs or fingerlings must originate from organic sources and must not be
14 Seafood Watch® Farmed Tilapia Report May 16, 2006
genetically manipulated or treated with hormones. All sources of water are evaluated as well as possible pollution threats, and depredation measures that do not physically harm predatory animals are preferred. Farm practices must be documented and adherence to standards must be monitored by third party auditors, and inspections are conducted at least annually and may be unannounced. The farm must supply information regarding its production and storage sites and its culture methods, including type and numbers of animals stocked, feeding schedule, hygienic measures, and the use of fertilizers. NaturLand regulations also cover processing and product quality and transport, as well as social standards for workers.
As is evident, there are a range of culture environments used for tilapia, and sustainability varies substantially as a result. Unlike commercial capture fisheries that can be characterized across large regions, aquaculture practices can vary from farm to farm. Tilapia aquaculture practices are perhaps the most diverse among all aquaculture species in the world (De Silva et al. 2004), and the environmental effects of aquaculture are still emerging. For tilapia, effects range from beneficial, where some farms are able to produce more edible fish than is consumed as feed, to detrimental, where some farms actually reduce production of the global fish supply. Sustainability is highest for integrated farms with no access to natural waters, moderate for semi- intensive and intensive methods using enclosed ponds and tanks, and lowest with semi-intensive and intensive methods using nets, cages, or raceways, or unenclosed ponds and tanks. Seafood Watch’s ability to summarize these methods and systems for country-wide recommendations is difficult, as they vary from farm to farm, but generally Seafood Watch® suggests avoiding farmed tilapia from China and Taiwan, and recommends U.S.-farmed tilapia and organic tilapia as Best Choices, and tilapia from other countries as a Good Alternative.
Availability of Science
Most of the cultured tilapia on the U.S. market is produced in China and Taiwan (information from “China” often includes Taiwan, as a province of China); however, tilapia aquaculture is practiced worldwide. Detailed information is not generally as readily available from Southeast Asia as it is from domestic producers. For this report, Seafood Watch® has summarized global (especially Chinese) tilapia culture practices. In the U.S., we have concentrated on California because it is the largest single producing state, but further research should assess each state separately. With regard to organic regulations, this report concentrates on a major aquaculture label, NaturLand of Germany, but there are various other sources for “certified,” “natural,” and “organic” products.
Important impacts that are not considered in this report include water and land use, the energy required to operate more sophisticated flow-through and recirculating farms (raceways and tanks, respectively), and the thermal input needed for tropical tilapia in cold-water environments, common in North American farms. Tyedmers (2000) also expresses a growing, general concern regarding fossil fuel use in food production systems. Thus, the true sustainability of farms in the U.S. and other temperate regions may be less favorable than reported here should these additional factors be included.
15 Seafood Watch® Farmed Tilapia Report May 16, 2006
Market Availability
Common and market names: The species of greatest importance in tilapia culture are the Nile tilapia (Oreochromis niloticus), Mozambique tilapia (Oreochromis mossambicus), and blue tilapia (Oreochromis aureus), and their hybrids (Martins et al. 2004). Besides “tilapia,” market names include St. Peter’s fish, based on the biblical account of the multiplication of fish by Jesus. When used for sushi or sashimi, tilapia is commonly sold as izumidai.
Seasonal availability: Tilapia is available year-round.
Product forms: Tilapia is available as whole fish (live, fresh, or frozen) or as fresh or frozen fillets. In 2005 China was the largest supplier of frozen tilapia product (whole and fillets, 67%), and Ecuador, Honduras and Costa Rica accounted for 92% of imported fresh fillets (data from NMFS Fisheries Statistics).
80,000 70,000 60,000
50,000 Imports 40,000 U.S. Production 30,000 Consumption 20,000 From Domestic Sources 10,000 0 1997 1998 1999 2000 2001 2002
Figure 6. Quantity (mt) and sources of tilapia on the U.S. market, including imported product, domestic aquaculture production, and consumption from domestic sources (data from National Marine Fisheries Service Fisheries Statistics). Quantity of U.S. consumption of domestic tilapia is estimated from domestic production less exports. Consumption of domestic product is likely under-estimated because “exports” include imported product that is altered in the U.S. and then exported.
Production, import and export sources and statistics: Sources of tilapia for U.S. consumption include domestic and imported product. Imports far exceed domestic product in the U.S. market (Figure 6).
For the six years from 2000 to 2005, total imports of tilapia to the U.S. increased an average of 27.5% per year (by weight). In 2000, the U.S. imported 40,469.0 metric tons (mt) worth US $101.4 million; in 2001, 56,337.4 mt worth $127.8 million; in 2002, 67,187.5 mt worth $174.2 million; in 2003, 90,246.3 mt worth $241.2 million; in 2004, 112,939.2 mt worth $297.4 million; and in 2005, 134,868.6 mt worth $393.0 million. Quantities of tilapia imported to the U.S. from the top ten exporting nations are listed below in Table 2. China dominates the production of
16 Seafood Watch® Farmed Tilapia Report May 16, 2006 many cultured species, and China and Taiwan continue to provide the vast majority of U.S. tilapia imports (in 2005, 75.9% by weight).
Table 2. Tilapia imported to the U.S. from 2000 to 2005, the top ten exporting nations only. Data from National Oceanographic and Atmospheric Administration (NOAA) Fisheries Office of Science and Technology. Weight (metric tons) Portion Exporting of 2005 Nation 2000 2001 2002 2003 2004 2005 Total China 13,544.0 13,593.5 26,525.6 45,611.8 60,065.6 75,006.1 55.7% Taiwan 17,729.2 29,808.7 23,667.0 22,414.7 27,690.7 27,210.0 20.2% Ecuador 3,447.2 5,159.2 6,903.4 9,726.6 10,411.7 10,932.2 8.1% Indonesia 1,220.5 2,217.7 2,575.0 3,488.1 4,253.1 6,638.2 4.9% Honduras 1,046.2 1,437.7 2,873.6 2,856.6 4,041.7 6.471.8 4.9% Costa Rica 1,341.9 3,108.9 3,208.3 4,000.2 4,106.6 3,847.7 2.9% Thailand 198.1 259.6 614.9 1,067.6 877.9 1,032.2 0.8% Brazil 1.8 8.0 160.8 235.2 323.1 972.6 0.7% Panama 345.3 352.6 345.3 240.9 288.7 718.8 0.5% El Salvador 77.7 0.0 77.7 188.6 257.8 306.7 0.2%
Since the year 2000, tilapia imports have originated from more than 40 nations. In addition to the top ten exporting nations listed in Table 2, the U.S. also received tilapia product from Argentina, Bangladesh, Belize, Burma, Cambodia, Canada, Cayman Islands, Chile, Columbia, Dominican Republic, Fiji, Ghana, Grenada, India, Jamaica, Japan, Macao, Malaysia, Mauritius, Mexico, New Zealand, Nicaragua, Pakistan, Peru, Philippines, South Korea, South Africa, Spain, Suriname, Tanzania, Trinidad & Tobago, Uganda, United Kingdom, Venezuela, and Viet Nam.
In 2005, exports from the U.S. totaled 3,950.3 mt, principally to Mexico (88.0%). Export does not necessarily mean that the product was produced in the U.S., however, as “exports” include tilapia that has been imported, processed, and then re-exported.
Analysis of Seafood Watch® Sustainability Criteria for Aquaculture Species
Criterion 1: Use of Marine Resources
A major environmental concern for aquaculture is the use of fishmeal and fish oil in feeds, known as compound feeds. Reliance on compound feeds to meet protein and lipid requirements varies with the species being farmed and the aquaculture methods used. A substantial portion of the world’s wild-caught fish is converted to fishmeal and fish oil for these compound feeds in aquatic farms, as well as for feeds for terrestrial farms (e.g., chicken and cattle feeds). The production of aquafeeds is one of the fastest expanding agricultural industries in the world, growing over 30% per year (Tacon 1997 and references cited therein). Compared to terrestrial agriculture, aquaculture is a much more efficient method of producing protein. Concern is still warranted, however, because inefficient use of compound feeds for aquaculture creates the unsustainable situation of using more wild fish as feed than farm fish produced.
17 Seafood Watch® Farmed Tilapia Report May 16, 2006
According to Naylor et al. (2000) the growth in fishmeal use helps to explain recent patterns in ocean fish capture. “Between 1986 and 1997, 4 of the top 5, and 8 of the top 20 capture species were used in feed production for the aquaculture and livestock industries. These species— anchoveta, Chilean jack mackerel, Atlantic herring, chub mackerel, Japanese anchovy, round sardinella, Atlantic mackerel and European anchovy—are all small pelagic fishes” (Naylor et al. 2000). The wild fish used in aquafeed production are on the decline (Subasinghe et al. 2003), and the world’s increasing reliance on fishmeal increases the stocks’ vulnerability (Black 2001).
A useful measure of marine resource utilization is the wild input to farmed output ratio. This ratio evaluates how much wild fish (by weight) are used as feed to produce farmed fish. A ratio greater than 1 indicates that the aquaculture fishery is not producing alternatives to wild-caught fish, but rather is reducing the global availability of fish for consumption. Below is a discussion of two estimates of wild input to farmed output ratios for tilapia, the first from Naylor et al. (2000) and the second from Tacon (2004). The work by Naylor et al. (2000) is dated. It has been widely read so it is reviewed here, but needs careful interpretation. It has sparked controversy, partly due to the issue of interpretation and partly due to the larger controversial debate regarding whether aquaculture practices are generally sustainable. The Tacon (2004) paper reports the use of compound feeds for tilapia in a more transparent manner and also provides future estimates.
From Naylor et al. (2000), Table 3 shows that tilapia feeds contain 16% combined fishmeal and fish oil, and that 35% of the total tilapia production in 1997 used compound feeds. They calculated the ratio of input from wild-caught fish to farmed output for tilapia as 1.41. In other words, they calculated that 1.41 kg of wild fish are used to produce 1 kg of farmed tilapia. However, a careful examination of Table 3 reveals that the ratio of 1.41 was obtained by dividing “Wild fish used for fishmeal” by “Production with compound feeds” (466/331 = 1.41). Thus it is more accurate to use the 1.41 ratio when characterizing the sustainability of tilapia fed compound feeds. However, Naylor et al. (2000) reports that 65% of the tilapia produced were not fed compound feeds (Table 3). A more complete picture acknowledges that a substantial portion of tilapia farms do not use compound feeds, and a global ratio can be calculated as “Wild fish used for fishmeal” divided by “Total production” (466/946) which yields 0.49. However, Tacon (2004) predicts that the percentage of tilapia production using compound feeds will rise to 60% in 2010 as demand for tilapia grows.
18 Seafood Watch® Farmed Tilapia Report May 16, 2006
Table 3. From Naylor et al. (2000).
The wild input:farmed output ratio of 1.41 for tilapia fed compound feeds is not surprising. Tilapia are herbivorous/omnivorous, a feeding strategy that makes relatively efficient use of marine resources. Consider the ratio of 3.16 for salmon, a carnivore (Table 3).
From Tacon (2004) one can calculate the wild input to farmed output ratio for tilapia in the year 2002, as well as estimates for 2005 and 2010, by using the equation:
Total Fishmeal x Conversion Used Rate = Input:Output Total Tilapia Production
The Food and Agriculture Organization of the United Nations (FAO) assumes a Conversion Rate of 5:1 for wild pelagics to fishmeal and fish oil. From Tacon (2004) the input:output ratio in 2002 was estimated to be 0.27. In 2005 the ratio is estimated to be 0.18, and in 2010, 0.14.
A third method to calculate the wild fish input to farmed fish output is with the equation:
Conversion Rate Feed of wild fish to x Inclusion Rate x Conversion = Input:Output fishmeal/oil Ratio (FCR)
Conversion rates can vary based on the species of fish, season, condition of fish, and efficiency of reduction plants (Tyedmers 2000) (reduction is the process by which wild fish are processed into fishmeal and/or fish oil). For this method, we use a fishmeal conversion rate of 22%. This has been suggested by Tyedmers (2000) as a reasonable year-round average conversion rate and means that 4.5 units of wild fish from reduction fisheries are needed to produce 1 unit of fishmeal. Additionally, we use a fish oil conversion rate of 12%, or 8.3 units of wild fish to
19 Seafood Watch® Farmed Tilapia Report May 16, 2006
produce 1 unit of fish oil, which was suggested by Tyedmers (2000) as a representative year- round average for Gulf of Mexico menhaden.
The inclusion rate is the percentage of fishmeal/oil included in aquafeed, reflecting different dietary requirements for specific animals. For tilapia the estimated inclusion rates for 2002 were 5% for fishmeal and 1% for fish oil; in 2005 it was 3% and 1%, respectively; and for 2010 it is 2% and 1%, respectively (Tacon 2004). Some researchers sum the fishmeal and fish oil inclusion rates for a total inclusion rate. However, adding meal and oil together neglects the fact that the same fish are used to produce fishmeal and fish oil, thus double-counting wild fish inputs. For this report, Seafood Watch® did not sum fishmeal and fish oil rates but instead uses the larger of the figures, which, in this case, is for fishmeal.
The Feed Conversion Ratio (FCR) is the ratio of feed to farmed biomass increase (wet weight). Estimates by Tacon (2004) predict that tilapia FCRs will fall from 2 to 1.6 by 2010. Below are the ratios calculated for 2002, showing 0.45, based on the more limiting factor, fishmeal.
Product Conversion Inclusion Rate FCR Input:Output Rate meal 4.5 x 0.05 x 2 = 0.45 oil 8.3 x 0.02 x 2 = 0.33
Developing countries (e.g., China) are increasingly utilizing compounded feeds in fish farms, including tilapia farms. Aquaculture in Asia continues to intensify due to increased scarcity and value of land and freshwater resources. There is also concern regarding the huge volume and continued increase in production of farmed carp and tilapia in Asia. Intensification could create significant increases in fishmeal and fish oil content of feed, in turn putting more pressure on pelagic fisheries (Tacon 1996; Naylor et al. 2000). However, a recent estimate of future trends (Tacon 2004) predicts that, because wild pelagic stocks have remained stable over the past decade, aquaculture will be forced to reduce its reliance on these stocks. In addition, the majority of the above calculations show that tilapia grown using compound feeds is still a net producer of edible fish protein as the Fish In: Fish Out ratio is substantially less than 1:1.
Although laboratory tests using plant proteins (e.g., soy) show promise for alternatives to fishmeal and fish oil for omnivorous fish such as tilapia, actual practices are another story. Many herbivorous/omnivorous finfish are given over-formulated feeds exceeding requirements based on lack of sufficient dietary information (Tacon 1996; Naylor et al. 2000). Thus, effective management must include oversight of feed content and regimen. NaturLand organic certification requires using minimal amounts of fishmeal and fish oil in feeds, as well as transparent reports on feed practices. They conduct regular and unannounced audits that include evaluating the feeding regimen.
Synthesis Depending on how calculations are made, various estimates of Fish In to Fish Out ratios for tilapia culture range from substantially less than 1.00 to 1.41. In nearly all cases, this ratio is less than 1:1, indicating that tilapia culture results in a net gain of edible fish protein. There is therefore a low conservation concern about the current use of marine resources in most culture
20 Seafood Watch® Farmed Tilapia Report May 16, 2006
practices. However, some caution is warranted, especially in China where over-formulation of feeds may result in the consumption of more wild fish than necessary for optimal tilapia growth.
Use of Marine Resources Rank:
Low Moderate High Critical __
Criterion 2: Risk of Escaped Fish to Wild Stocks
Tilapia are native to Africa and the Middle East; however, their adaptability to a wide range of environmental conditions predisposes them to invade non-native habitat. They threaten native fishes because they will feed on juvenile native fish as well as on native plants that act as refugia for juveniles. Tilapia are now one of the most widely distributed exotic fish in the world, second only to common carp, as their introduced range now stretches to nearly every continent (Figure 7) and includes 90 different countries (De Silva et al. 2004). As they have been transported around the world in the last 50 to 60 years, tilapia have established themselves in nearly every warm-water habitat to which they have been introduced (Canonico et al. 2005). However, tilapia are not yet in every freshwater system in every country within their introduced range, thus precaution in tilapia farming can help prevent the further spread of tilapia species to additional native habitat by preventing or reducing ongoing escapes.
Figure 7. Global introductions of Mozambique and Nile tilapia (FAO 1998).
Escaped fish pose several threats to wild stocks, including disease and parasite transfer (Criterion 3) and genetic impacts. Genetic variation is the foundation of biodiversity which sustains robust production, prevents inbreeding depression, and stores the raw material (DNA) necessary for new products and increased yields. Genetically altered or monosex aquaculture populations have the potential to compete with and interbreed with wild stocks, which can impact the genetic
21 Seafood Watch® Farmed Tilapia Report May 16, 2006 make up of wild populations. In many cases tilapia stocks have interbred with local populations, leading to decreased genetic diversity (Canonico et al. 2005).
Production levels of commercial tilapia product are much higher outside the species native range than within it. Of the tilapia species and hybrids cultivated, the most widely introduced is O. mossambicus, which is considered a pest and a threat to native diversity (Choo 2001 and references cited therein). Nonetheless, some have argued that tilapia introductions have also been considered to have societal value; for example by providing algae and insect control and food supplies (McIntosh et al. 2003; DeSilva et al. 2004).
Tilapias—most commonly the Mozambique tilapia, Nile tilapia, and blue tilapia—have been introduced to the U.S. via several different ways and for a variety of reasons. Means of introduction for these species include releases or escapes from fish farms, hatcheries, zoos, and aquariums, as well as intentional introductions for aquatic plant and insect control, for use as a bait and sport fish, and for use as a food or commercial fish.
The most widely introduced tilapia in the U.S. is the Mozambique tilapia (Figure 8). The IUCN/SSC Global Invasive Species Database (http://www.issg.org/database/welcome/) includes Mozambique tilapia in its list of 100 of the World’s Worst Invasive Alien Species. This species is now considered established in seven U.S. states including Arizona, California, Colorado, Florida, Hawaii, Idaho, and locally in Texas. Mozambique tilapia is formerly considered locally established but no longer extant in Georgia, Montana, and North Carolina. It is reported in Alabama, Illinois, and New York as well. In Hawaii, Mozambique tilapia is suspected to be a threat to native species such as striped mullet (Mugil cephalus). Mozambique tilapia has also substantially contributed to the decline of the desert pupfish (Cyprinodon macularius) in the Salton Sea area, in California.
Figure 8. Mozambique tilapia invasions in the U.S. (USGS NAS 2005).
Nile tilapia is established in Mississippi and may be established in a large reservoir bordering Florida and Georgia (Figure 9). Nile tilapia has also been reported from Alabama and Arizona. The USGS reports the impact of its introduction as unknown.
22 Seafood Watch® Farmed Tilapia Report May 16, 2006
Blue tilapia has been introduced via escapes or releases from aquaculture farms, zoological parks, and aquariums (Figure 10). Individuals and private companies have introduced them for sport fish, food, aquatic plant control, and bait. Blue tilapia is established or possibly established in Arizona, California, Florida, Nevada, North Carolina, and Texas. It may be established in Colorado, Idaho, Oklahoma, and Pennsylvania. Blue tilapia is reported in Alabama, Georgia, and Kansas. In Florida, blue tilapia is considered the most widespread foreign fish.
Figure 9. Nile tilapia invasions in the U.S. (USGS NAS 2005).
Blue tilapia competes with native species for spawning areas, food, and space. It is considered a major management problem in the Taylor Slough portion of Everglades National Park. Other impacts include changes in fish community structure and a dramatic reduction in native fishes.
Figure 10. Blue tilapia invasions in the U.S. (USGS NAS 2005).
Escaped tilapia are more likely to be male than female, as all-male tilapia stocks are desirable to avoid over population, reduce territorial behavior, and standardize size range at harvest. One
23 Seafood Watch® Farmed Tilapia Report May 16, 2006 method for creating an all-male population is hormonal treatment of tilapia fry. In addition, Genetically Male Tilapia (GMT) can be produced over several generations, resulting in animals with two Y chromosomes that yield all or almost all male progeny (Figure 2). The impact of these genetic modifications on wild species is not well known, though it is likely that escapees from all-male stocks are less likely to establish feral populations.
Tilapia farms in temperate regions such as Canada and parts of the U.S. require thermal inputs for fish survival, thus escaped animals are less likely to establish themselves in these colder waters. However, tilapia have established themselves in thermal refugia within cold-water regions; for example in the discharge from power plants. NaturLand’s organically certified products require strict precautions against tilapia escapes into non-native waters, but escapes are not always obvious; thus it is unknown how effective those regulations are. Given the lack of standardized organic regulations, the serious issues involving escapes, and the difficulties inherent in assessing the extent of escapes, moderate concern is warranted for organic-certified tilapia product.
Despite its global distribution, the ecological impacts of tilapia introductions are not well understood. A review by De Silva et al. (2004) concludes that the socioeconomic benefits outweigh the environmental damage done by tilapia introductions and that factors other than introduction of tilapia have contributed to the decline of native species. A review by Canonico et al. (2005), however, describes a number of case studies that correlate tilapia introductions with the decline of an endangered fish in Nevada and Arizona, the decline in native fish in Madagascar, and the decline of native cichlid species in Nicaragua and Kenya, as well as tilapia that have become the dominant species in Lake Chichincanab, Mexico. In Australia, eradication efforts for introduced tilapia have failed. Both reviews are credible reports, but De Silva et al. (2004) heavily weigh the socioeconomic factors into their conclusion while Seafood Watch® does not include socioeconomic effects in its sustainability recommendations because short-term economic benefits can be outstripped by long-term loss of biodiversity. A report to the Global Invasive Species Program (Guiérrez and Reaser 2005) lists significant adverse effects from tilapia introductions, including “devastation” to Lake Sampaloc in the Philippines, and a complete ecosystem change in Costa Rican aquatic systems that involve not only native fish species but also plankton and aquatic insects.
Escaped fish can also compete with or eradicate other species. In freshwater systems the introduction of invasive species is considered a leading cause of species endangerment and extinction (Claudi and Leach 1999; Harrison and Stiassny 1999; Sala et al. 2000). Introductions most commonly result from aquaculture practice. Tilapia in closed systems pose a moderate level of risk of escapes through effluent drainage or during floods or storms that cause system overflow; however, with open systems escapes are inevitable and pose a high conservation concern. According to Canonico (2005): “Researchers with direct experience in observing the effects of established, introduced populations of tilapias on native fish will say, without exception, that no tilapia species should be introduced into natural waters in which they are not native and in which they could become established.” Even “closed” ponds, tanks, and raceways are periodically compromised by fish escapes. Unless these systems are enclosed in a structure, storms will overflow the system and allow escapes. Thus, Dr. Canonico recommends enclosed ponds, tanks, and raceways where there is no access to natural waters.
24 Seafood Watch® Farmed Tilapia Report May 16, 2006
Synthesis Tilapias readily invade and naturally reproduce in warm waters where they are introduced. They are currently established throughout much of the world, but experts strongly suggest that non- native tilapia should not be farmed in new or pristine areas because escapes are inevitable, with serious negative results. Non-native tilapia populations have been found to compete with, supplant, or “devastate” wild cichlids and other native species. Eradication efforts in Florida have failed. Continued escapes are expected, particularly in open systems (nets, cages, and flow- through raceways), meriting high concern. However, even relatively closed systems (ponds, recirculating tanks), unless enclosed in a structure, are still compromised by storm events and merit continued concern.
Risk of Escaped Fish to Wild Stocks Rank:
No access to natural waters: Low __ Moderate __ High __
Enclosed ponds & tanks: Low __ Moderate __ High __
Nets, cages & raceways, unenclosed ponds & tanks: Low __ Moderate __ High __
Criterion 3: Risk of Disease and Parasite Transfer to Ecosystem
Though tilapia are relatively resistant to disease, transmission of disease and parasites from aquaculture populations to wild fish populations or vice versa can be a major threat to cultured and wild fish populations. Bacteria such as Streptococcus, for example, can pose a serious threat to the tilapia culture industry. The avenues of transmission include escaped fish, which can transfer disease and parasites from cultured fish to the wild, and cages open to the environment, which may release parasites to downstream locations or may allow the transfer of wild diseases to the cultured population.
Though there are few reports regarding disease and parasite transfer from tilapia introductions, Dr. Kevin Fitzsimmons of the University of Arizona notes that, in California, stocked tilapia become infected with the parasite Trichodona epistylis from wild stocks (personal communication). In Mexico and Nicaragua, on the other hand, introduced tilapia have infected native cichlid fish with parasites (Canonico et al. 2005).
Organically certified tilapia farms (e.g., by NaturLand) are required to focus on preventing outbreaks by maintaining natural environments and behaviors, and then to promptly treat infections.
Because tilapia readily invade habitats, and because introductions are worldwide and there is at least one known case of parasite transfer, caution is warranted regarding transmission of diseases and parasites to wild stocks despite the lack of specific data. Thus, open systems (nets, cages,
25 Seafood Watch® Farmed Tilapia Report May 16, 2006
raceways) are rated as a moderate risk for disease transfer, while concern is low for farms meeting organic standards and for closed systems (ponds, tanks).
Risk of Disease and Parasite Transfer to Ecosystem Rank:
Organic, enclosed ponds & tanks: Low Moderate High
Nets, cages & raceways, unenclosed ponds & tanks: Low Moderate High
Criterion 4: Risk of Pollution and Habitat Effects
Aquaculture effects on the environment can be either negative or positive. Ponds can have a positive effect on soil and water conservation, by slowing down the erosion caused by runoff water and reducing downstream flooding, while nutrient-rich pond water can also help irrigate vegetable farms and make productive use of marginal land, such as irrigation trenches. It is also possible to use tilapia as a means to improve water quality because they consume excess plant material. However, there are also a number of negative effects of tilapia aquaculture to consider.
Negative effects of aquaculture are most generally found with the intensive culture of carnivorous fish species and shrimps (Choo 2001); however, tilapia aquaculture has also been associated with environment degradation. Excess nutrient use and the use of chemicals and hormones can all have negative impacts on wild species and ecosystems when released into the environment as effluent. This risk is minimized when closed-systems are used, as ponds have the natural capacity to assimilate wastes, but open systems that continuously exchange water with the environment can drastically affect water bodies downstream. Nets, cages, and flow- through raceways rely on the environment to deliver oxygenated water and to remove fish waste, excess feed, and chemicals, such that the effluent is continuously released without being treated. In other closed systems, effluent is released only after been treated, but can still be released untreated if the systems are breached in storms or other events.
The excess nutrients released in tilapia aquaculture can cause eutrophication of water bodies, which results in changes in water chemistry, deoxygenation, and enrichment of sediments with organic waste, and eventually to the loss of benthic diversity (Kelly and Elberizon 2001). One case study in Brazil found a link between intensive tilapia farming in Lago Paranoá and an increase in phosphorus, chlorophyll a, and blue-green algae concentrations in the lake (Canonico et al. 2005). The cultured fish feeding on the lake bottom stirred the sediment and released nutrients into the water column. These excess nutrients allowed increased growth of blue-green algae, which later decomposes and depletes dissolved oxygen in the water column. If dissolved oxygen (DO) levels are depleted low enough in this way it can lead to massive fish die-offs.
Chemical treatments are typically used to control disease and parasites in cultured tilapia populations. Cultured tilapia are relatively disease resistant, however, and therefore require few chemical treatments; thus the use of large amounts of chemicals is usually a sign of poor husbandry (Black 2001). Once applied though, chemicals and hormones may remain stored for
26 Seafood Watch® Farmed Tilapia Report May 16, 2006
years in the sediment below culture ponds, and released into the environment when the ponds are breached in the event of flooding or other event.
Hormone treatments are used on some tilapia farms to produce all-male populations to control reproduction and maximize biomass production. There are three common methods used to create all-male stocks. Sorting fingerlings by hand to separate the sexes is best for consumer and farm worker health by minimizing any exposure to potentially toxic chemicals. Alternatively, using Genetically Modified Tilapia (GMT) (Figure 2) as brood stock produces a natural product for consumers that is not considered a Genetically Modified Organism (GMO), but that may be excluded from organic certification (e.g., NaturLand of Germany). The least ecologically desirable but most commonly practiced method is to treat fry with methyl testosterone to cause sex reversal, which is a cause for concern regarding worker health.
Tilapia production systems vary greatly because the species is tolerant to a wide range of farm methods. Production is mainly found in freshwater, but includes brackish water and even seawater. It is therefore difficult to generalize about tilapia production practices, particularly for a large, rapidly developing country like China, the major producer of tilapia on the U.S. market. Even if we exclude China, it is still difficult to generalize for any country because practices vary widely from farm to farm. Currently, organic certification by NaturLand requires that effluent not harm surrounding ecosystems, and encourages integrated aquaculture; however, it is unclear how NaturLand ensures this requirement is being met.
One generalization we can make is that increased intensification coupled with an open system represents the highest risk of pollution and habitat damage. This generalization is helpful, but there are still exceptions. The example of Ecuador (see Criteria 5) highlights the complexity of rating the sustainability of farming practices for individual countries.
Dr. Peter Perschbacher, of the University of Arkansas’s Department of Aquaculture and Fisheries, began research in 1973 on environmental interactions of tilapia in aquaculture. Dr. Perschbacher has expressed concern about pollution and habitat damage from intensive systems without clear evidence of treatment or closed systems, and without alternatives to hormone sex reversal of fry. In particular, there is growing concern regarding tilapia from some areas of Central America. Currently, the greatest growth in the tilapia market is for fresh fillets from Central and South America (Watanabe et al. 2002) and several major producers in Honduras and other countries are using intensive cage methods. Some large producers in Costa Rica exchange water every 20 minutes while others do not. Methyl testosterone is used to create all-male populations, which may be released into the environment from hatcheries. All this suggests caution is warranted fro Central America where open farming systems are being employed.
In contrast, effluent regulations in the United States are governed at the federal level by the Environmental Protection Agency (EPA). In 2004 the EPA released effluent limitation guidelines for domestic culture practices. A best management practice recommends water recirculation or using effluent to irrigate farm crops. A synopsis by the National Sea Grant Law Center (http://ag.arizona.edu/azaqua/extension/BMPs/effluent.pdf) summarizes the Federal Register regulations, reproduced below.
27 Seafood Watch® Farmed Tilapia Report May 16, 2006
The Final Rule Applies To: • Both commercial (for-profit) and non-commercial (generally, publicly owned) operations that: o Produce aquatic animals for food, recreation, restoration of wild populations, pet trade, and other commercial products; AND o Produce, hold, or maintain at least 100,000 pounds a year, in flow-through and re- circulating systems, that discharge wastewater at least 30 days a year (used primarily to raise trout, salmon, hybrid striped bass and tilapia); OR o Produce, hold, or maintain at least 100,000 pounds a year, in net pens or submerged cage systems (primarily salmon operations). • Net pen systems rearing native species released after a growing period of no longer than 4 months to supplement commercial and sport fisheries are exempted from the rule. The Rule Requires: • All applicable facilities must: o Prevent discharge of spilled drugs and pesticides and minimize discharges of excess feed; o Regularly maintain production and wastewater treatment systems; o Keep records on numbers and weights of animals, amounts of feed, and frequency of cleaning, inspections, maintenance, and repairs; o Train staff to prevent and respond to spills and to properly operate and maintain production and wastewater treatment systems; o Report the use of experimental animal drugs or drugs that are not used in accordance with label requirements; o Report, orally and in writing, any failure of, or damage to, a containment system and report any spills of drugs, pesticides or feed that will result in a discharge to waters of the U.S.; and o Develop, maintain, and certify a Best Management Practice (BMP) plan that describes how the facility will meet the requirements. • Flow-through and re-circulating discharge facilities must minimize the discharge of solids such as: o Uneaten feed, settled solids, and animal carcasses. • Open water facilities must additionally: o Use active feed monitoring and management strategies to ensure the least possible amount of uneaten feed accumulates beneath the nets; o Properly dispose of feed bags, packaging materials, waste rope, and netting; o Limit as much as possible wastewater discharges resulting from the transport or harvest of the animals; and o Prevent the discharge of dead animals in the wastewater.
Synthesis U.S. EPA regulations are comprehensive for effluent treatment for U.S. tilapia aquaculture farms, meriting low conservation concern regarding pollution and habitat effects from tilapia farms in the U.S. Similarly integrated farms rank as low conservation concern, as effluent is used for agriculture rather than being released into natural water bodies. Risk for organic product internationally may be low as well, but lack of demonstrated effectiveness warrants caution and a rating of moderate risk for organic tilapia. The risk of pollution is likewise
28 Seafood Watch® Farmed Tilapia Report May 16, 2006
moderate for semi-intense and intensive operations that are closed to the environment (ponds, tanks), but higher for semi-intense and intensively stocked, open systems (nets, pens, raceways). At present, there is also moderate but growing concern for pollution in China and Central America where rapid development of intensive cage culture continues.
Risk of Pollution and Habitat Effects Rank:
U.S.; integrated: Low Moderate High
Organic; all ponds and tanks; China; Central America: Low Moderate High
Semi-intensive and intensive nets, pens, raceways: Low Moderate High
Criterion 5: Effectiveness of the Management Regime
Because aquaculture products are becoming more popular, and operations more intensive, it is vital that effective management regulations be implemented. However, the implementation of effective management practices is inherently more difficult for aquaculture than for wild capture fisheries. Capture fisheries are regulated across large regions by gear, size, area, and seasonal regulations, but the aquaculture industry can vary greatly at the level of individual farms. In addition, tilapia aquaculture is still emerging, thus regulatory oversight for tilapia is not as comprehensive as it is for shrimp, salmon, and channel catfish (Boyd et al. 2005).
In conducting research for this report, little reliable information was found regarding specific management practices for China, though FAO provides some information on its website, at National Aquaculture Legislation Overview (see http://www.fao.org/documents/show_cdr.asp? url_file=/docrep/003/w7499e/w7499e06.htm). According to Dr. Kevin Fitzsimmons, best management practices are developed and distributed by the Chinese Aquatics, Products, Processing, and Marketing Association, but practices are not monitored. It is clear that China continues to increase greatly its production of aquaculture products, including tilapia. Increases in production are possible through increased resource allocation (e.g., building more ponds), and intensification of culture methods, and recent trends in Asia include governmental dam-building programs to create new areas of freshwater. Figure 11 shows that total freshwater area in China is increasing.
29 Seafood Watch® Farmed Tilapia Report May 16, 2006
Figure 11. Annual changes in the use of inland aquatic and land resources for freshwater aquaculture in China (from Rana 1997).
Ponds and reservoirs are the principal types of water bodies used for freshwater aquaculture production. Increased production has also been achieved through increased yields. For ponds, the Chinese national average yield has increased from 1.39 mt/ha/yr in 1985 to around 4 mt/ha/yr in 1995. More recently, the bulk of commercial culture in China has changed from semi- intensive pond methods to intense freshwater cage methods (Kelly and Elberizon 2001), which substantially decreases sustainability and is considered a high conservation concern.
Rana (1997) reports that China’s rapid transformation to a market economy reveals several shortcomings:
a) Incomplete control of licensing for small-scale farms on private lands; b) competition with other industrial sectors for land and aquatic resources, particularly in coastal regions; c) inadequate infrastructure for the rapidly expanding sector; d) degradation of water quality and culture environments through urbanization, industrialization and uncontrolled intensification; e) limited processing capacity for aquaculture products; f) slow or, in some cases, no implementation of market-oriented policies on price deregulation; g) inadequate fish distribution system; h) managers and workers inadequately trained for modern operations; i) unpredictable fluctuations in the quantity and quality of seed, particularly of high-value freshwater and marine finfish and shellfish species; and j) poorly maintained culture facilities.
Although reliable information about individual tilapia farm practices is not publicly available for most countries, we can look to expert opinion. For example, Ecuador is the third largest exporter to the U.S. (Table 2), culturing tilapia from a small number of farms (approximately 20) (Tacon, Hawai’i Sea Grant College Program Sea Grant College Program, personal communication). According to Dr. Tacon, Ecuador’s largest farm uses intensive methods and discharges enough effluent from ponds to potentially be considered at high risk for pollution. However, the effluent
30 Seafood Watch® Farmed Tilapia Report May 16, 2006
is used as a resource to fertilize agricultural land, and this practice of integrated culture is thus desirable for sustainability. Dr. Tacon’s opinion is based on his extensive experience in aquaculture research and on personal observances of individual farms in Ecuador.
Based on interviews with experts, there appears to be a general lack of effective regulatory management within as well as elsewhere outside the U.S. (Drs. Fitzsimmons, Perschbacher, and Tacon, personal communication). In the U.S., effluent regulation is governed by the EPA, and food safety and drug usage is governed by the Food and Drug Administration (FDA). The EPA effluent limitations guidelines require a Best Management Practice (BMP) plan that recommends recirculation or using effluent to irrigate farms. According to Dr. Kevin Fitzsimmons, most California farms do indeed recycle their water or use it to irrigate farms. Regional centers (Figure 12), individual states, and counties govern other regulations such as permitting, construction, water use, waste discharge, stocking density, processing, and predator controls; however, regulations are not consistent among states.
Figure 12. Regulatory bodies of Regional Aquaculture Center (RAC) Programs in the U.S. From USDA http://aquanic.org/usda/usda.htm.
In the United States, tilapia are farmed in all five Regional Aquaculture Centers, including the states of Hawaii, California, Idaho, Arizona, North Dakota, Minnesota, Missouri, Vermont, New York, Texas, Louisiana, Alabama, Georgia, North Carolina, and Florida. The 1998 USDA Census of Aquaculture reported that California farms cultured the largest portion of tilapia by weight of any one state, producing 26% of all U.S. farmed tilapia.
This Seafood Watch® report has not exhaustively investigated management practices for the many nations exporting product to the U.S. market or for every state within the U.S. producing domestic product. Within the United States there are comprehensive regulations as well as non- governmental certification programs. For example, see the Marine Stewardship Council at http://www.msc.org/ for certified fisheries and product sources. Within the U.S. there is increasing interest toward certifying individual aquaculture facilities, including future USDA organic standards. In contrast, for this report Seafood Watch® found fewer governmental aquaculture regulations outside of the U.S.
Dr. Kevin Fitzsimmons provided information about management effectiveness for the U.S., particularly for California, and indicated that California effectively enforces tilapia management requirements. Bird predation can be a problem for aquaculture, and its control is termed
31 Seafood Watch® Farmed Tilapia Report May 16, 2006
depredation. The California Department of Fish and Game (CDFG) enforces depredation requirements that prohibit bird kills. The most common method of depredation in California farms is the use of greenhouse nets to cover tanks. CDFG also strictly prohibits transporting live tilapia in California because there is concern over their introduction to the productive Central Valley. In fact tilapia culture is prohibited north of the Tehachapi Mountains, a faunal migration barrier between central and southern California.
Organic certifiers (e.g., NaturLand) require reporting of all farm operations, regular and unannounced inspections, and demonstrated adherence to comprehensive regulations. Organic certification has great potential to increase management effectiveness because it adds additional regulatory attention and accountability to individual farms.
Synthesis The management practices of China appear to be ineffective. The U.S. has recently implemented national effluent limitation guidelines and Best Management Practice plans for aquaculture, and the U.S. management regime is effectively enforced; thus U.S. management, as well as organic management, is deemed effective. Most other countries appear to have underdeveloped management plans that merit moderate levels of concern.
Management Effectiveness Rank:
U.S.; organic: Effective Moderately Effective Ineffective
Other: Effective Moderately Effective Ineffective
China: Effective Moderately Effective Ineffective
32 Seafood Watch® Farmed Tilapia Report May 16, 2006
Overall Evaluation and Seafood Recommendation
Tilapia production is so widespread and varied globally that it prompts the reporting of two tables of sustainability ranks. The first table is rated according to the country of origin labeling that consumers encounter. The second table is for retailers and is more specific, allowing buyers to source their product based on farming practices.
Ratings in this report are based on five criteria for sustainability: 1) use of marine resources; 2) risk of escapes; 3) risk of disease transfer; 4) risk of pollution and habitat effects; and 5) management effectiveness. The use of some resources (energy, water and land use) are not considered here. If these additional factors were included, these ratings may be changed. See Boyd et al. (2005) for further discussion.
Because tilapia are omnivorous, the estimated global ratio of wild-caught fish input to farmed fish output is well below 1.0 (low concern). In contrast, escapes are a major cause for concern. Tilapia easily invade new habitat and are one of the most widely distributed exotic fish in the world. According to Canonico (2005): “Researchers with direct experience in observing the effects of established, introduced populations of tilapias on native fish will say, without exception, that no tilapia species should be introduced into natural waters in which they are not native and in which they could become established.” Escapes are less likely for ponds and tanks enclosed within structures, but open systems (nets, pens, raceways) inevitably allow escapes and impose a high risk. Risk of disease and parasite transfer is less of a concern than fish escapes because tilapia are generally disease resistant. Effluent management is vital. Fish stocked in high densities and fed supplemental feeds greatly increases the risk of pollution. Nets, cages and untreated raceways increase the risk of pollution because waste cannot be managed or treated. Regulations in the U.S., especially those promulgated by the EPA, are comprehensive and thus management for U.S. tilapia is deemed to be a low conservation concern. Because of poor regulation of waste in China, management there is considered a high conservation concern. Management for South American countries is generally considered moderately effective.
This report focuses on the major importers to the U.S. market (China and Taiwan), and on U.S. production (particularly California). Many countries are combined into the rating Good Alternative because this report does not comprehensively address practices found in the numerous countries that export limited amounts of tilapia to the U.S. market. As with all aquaculture, sustainability varies greatly at the level of individual farms and buyers are encouraged to source product based on production practices rather than country of origin. We have also included research on organic standards, particularly NaturLand of Germany. A range of international organic standards exist for aquaculture, and USDA standards are forthcoming. Seafood Watch® recommends continued efforts to certify individual farms according to their responsible use of natural resources.
For consumers, Seafood Watch® suggests avoiding farmed tilapia from China and Taiwan, and recommends organic certified (e.g., NaturLand) and U.S. tilapia product as Best Choices. Seafood Watch® recommends tilapia from other countries (including Central America) as Good Alternatives when the Best Choices cannot be obtained. For retailers, Seafood Watch® recommends tilapia product from integrated farms with no access to natural waters as Best
33 Seafood Watch® Farmed Tilapia Report May 16, 2006
Choices; Seafood Watch® considers farms using semi-intensive and intensive methods in enclosed ponds and tanks as Good Alternatives; and Seafood Watch® suggests avoiding tilapia from farms using semi-intensive and intensive methods in nets, pens, and raceways or in unenclosed ponds and tanks, where escapes are inevitable and there is a high risk of pollution.
Table of Sustainability Ranks
For the consumer, by country.
Conservation Concern Sustainability Criteria Low Moderate High Critical Use of Marine Resources √ All Risk of Escapes to Wild Stocks √ US, Organic √ Other Risk of Disease/Parasite Transfer to Ecosystem √ US, Organic √ Other Risk of Pollution and √ Organic, √ US Habitat Effects Other
Effectiveness of Management √ US, Organic √ Other √ China
Overall Seafood Recommendation:
U.S., Organic Best Choices Good Alternatives Avoid
Other Best Choices Good Alternatives Avoid (Ecuador, Brazil, Honduras, Costa Rica)
China, Taiwan Best Choices Good Alternatives Avoid
34 Seafood Watch® Farmed Tilapia Report May 16, 2006
For the retailer, by production system and method (see pages 8-9 for definitions).
Conservation Concern Sustainability Criteria Low Moderate High Critical Use of Marine All Resources Nets, Cages, & Risk of Escapes to No Access to Enclosed Ponds Raceways, Wild Stocks Natural Waters & Tanks Unenclosed Ponds & Tanks Nets, Cages & Risk of Disease/ Enclosed Ponds Raceways, Parasite Transfer to & Tanks Unenclosed Ecosystem Ponds & Tanks All Ponds & Risk of Pollution and Nets, Cages & Integrated Recirculating Habitat Effects Raceways Tanks Effectiveness of Not Applicable Management
Overall Seafood Recommendation:
Integrated + No Access to Natural Waters Best Choices Good Alternatives Avoid
Semi-intense or Intensive + Enclosed Ponds Or Tanks Best Choices Good Alternatives Avoid
Semi-intense or Intensive + Nets, Cages & Raceways Or Unenclosed Ponds Or Tanks Best Choices Good Alternatives Avoid
35 Seafood Watch® Farmed Tilapia Report May 16, 2006
Acknowledgements
The Seafood Watch® Program would like to thank Dr. Claude Boyd, Department of Fisheries and Allied Aquacultures at Auburn University, Alabama, Dr. Kevin Fitzsimmons, Department of Soil, Water and Environmental Science at the University of Arizona, Dr. Gabrielle Canonico of the Sustainable Development and Conservation Biology Program at the University of Maryland, Dr. Peter Perschbacher of the Department of Aquaculture and Fisheries at the University of Arkansas at Pine Bluff, and Ms. Michele Thieme of the Conservation Science Program of World Wildlife Fund for reviewing all or a portion of this document.
Scientific review does not constitute an endorsement of Seafood Watch® on the part of the reviewing scientists; Seafood Watch® is solely responsible for the conclusions reached in this report.
36 Seafood Watch® Farmed Tilapia Report May 16, 2006
References
Black, K. D. 2001. Sustainability of Aquaculture. Pages 199-212 in K. D. Black, editor. The Environmental Impacts of Aquaculture. Sheffield Academic Press, Sheffield, UK. Boyd, C. E., A. A. McNevin, J. Clay, and H. M. Johnson. 2005. Certification issues for some common aquaculture species. Reviews in Fisheries Science 13:231-279. Canonico, G., A. Arthington, J. K. McCrary, and M. L. Thieme. 2005. The effects of introduced tilapias on native biodiversity. Aquatic Conservation: Marine and Freshwater Ecosystems 15:463-483. Choo, P.-S. 2001. Environmental effects of warm water culture in ponds/lagoons. Pages 76-98 in K. D. Black, editor. Environmental Impacts of Aquaculture. Sheffield Academic Press Ltd., Sheffield, UK. Claudi, R., J. H. Leach (eds). 1999. Nonindigenous Freshwater Organisms: Vectors, Biology and Impacts. CRC Press, Boca Raton, FL. De Silva, S. S., R. P. Subasinghe, D. M. Bartley, and A. Lowther. 2004. Tilapias as alien aquatics in Asia and the Pacific: a review. FAO Fisheries Technical Paper No. 453. Food and Agriculture Organization, Rome. 65 pp. El-Sayed, A.-F. M. 1999. Alternative dietary protein sources for farmed tilapia, Oreochromis spp. Aquaculture 179:149-168. FAO. 1998. Aquaculture Newsletter. Food and Agriculture Organization of the United Nations. Froese, R. and D. Pauly (eds.). 2001. FishBase. World Wide Web electronic publication. Available online at http://www.fishbase.org, accessed April 12, 2005. Gutiérrez, A. T. and J. K. Reaser. 2005. Linkages between Development Assistance and Invasive Alien Species in Freshwater Systems of Southeast Asia. USAID Asia and Near East Bureau, Washington, DC. Gupta, M. V., and B. O. Acosta. 2004. A review of global tilapia farming practices. Pages 7-12, 16 in Aquaculture Asia, published by NACA (National Aquaculture Centers in Asia- Pacific). Harrison, I.J., M. L. J. Stiassny. 1999. The quiet crisis: a preliminary listing of the freshwater fishes of the world that are extinct or ‘missing in action’. In Extinctions in Near Time, MacPhee RDE (ed.). Kluwer: New York, pp. 271–331. Kapuscinksi, A. R., and D. J. Brister. 2001. Genetic impacts of aquaculture. in K. D. Black, editor. Environmental Impacts of Aquaculture. Sheffield Academic Press Ltd., Sheffield, UK. Kautsky, N., H. Berg, C. Folke, J. Larsson, and M. Troell. 1997. Ecological footprint for assessment of resource use and development limitations in shrimp and tilapia aquaculture. Aquaculture Research 28:753-766. Kelly, L. A., and I. R. Elberizon. 2001. Freshwater finfish cage culture. Pages 32-50 in K. D. Black, editor. Environmental Impact of Aquaculture. Sheffield Academic Press Ltd, Sheffield, UK. Martins, C., C. Oliveira, A. P. Wasko, and J. M. Wright. 2004. Aquaculture. McIntosh, D., C. King, and K. Fitzsimmons. 2003. Tilapia for biological control of giant salvinia. Journal of Aquatic Plant Management 41:28-31.
37 Seafood Watch® Farmed Tilapia Report May 16, 2006
Naylor, R. L., R. J. Goldburg, J. H. Primavera, N. Kautsky, M. C. M. Beveridge, J. Clay, C. Folke, J. Lubchenco, H. Mooney, and M. Troell. 2000. Effect of aquaculture on world fish supplies. Nature 406:981-1082. NMFS. 2005. U.S. Foreign Trade. in. Personal communication from National Marine Fisheries Service, Fisheries Statistics Division, Silver Spring, MD. Website: http://www.st.nmfs.gov/st1/trade/, accessed June 2005. Rana, K. J. 1997. China, Regional Reviews. in Review of the state of world aquaculture, FAO Fisheries Circular, No. 886, Rev. 1, FAO, Rome. 163 p. Sala, O.E, F. S. Chapin, J. J. Armesto, E. Berlow, J. Bloomfield, R. Dirzo, E. Huber-Sanwald, L. F. Huenneke, R. B. Jackson, A. Kinzig, R. Leemans, D. M. Lodge, H. A. Mooney, M. Oesterheld, N. L. Poff, M. T. Sykes, B. H. Walker, M. Walker, D. H. Wall. 2000. Biodiversity -- global biodiversity scenarios for the year 2100. Science 287: 1770–1774. Subasinghe, R. P., D. Curry, S. E. McGladdery, and D. Bartley. 2003. Recent Technological Innovations in Aquaculture. Pages 59-74 in Review of the State of World Aquaculture, FAO Fisheries Circular No. 886 (Revision 2). Inland Water Resources and Aquaculture Service, Fishery Resources Division, FAO Fisheries Department. Food and Agriculture Organization of the United Nations. Rome, 2003. Tacon, A. G. J. 1996. Feeding tomorrow's fish: Keys for sustainability. Pages 11-33 in Workshop of the CIHEAM Network on Technology of Aquaculture in the Mediterranean (TECAM). Zaragoza; CIHEAM-IAMZ, Mazarrón, Spain. Tacon, A. J. 1997. Aquafeeds and feeding strategies. in Review of the State of World Aquaculture, FAO Fisheries Circular No. 886 (Revision 1). FAO Inland Water Resources and Aquaculture Service, Fishery Resources Division, Fisheries Resources Division. Food and Agriculture Organization of the United Nations. Rome, 1997. Tacon, A. G. J. 2004. Use of fish meal and fish oil in aquaculture: a global perspective. Aquatic Resources, Culture and Development 1:3-14. Tyedmers, P. H. 2000. Salmon and Sustainability: The biophysical cost of producing salmon through the commercial salmon fishery and the intensive salmon culture industry. Ph.D. Thesis. The University of British Columbia: 272 pages. USGS NAS. 2005. Oreochromis mossambicus. in. Nonindigenous Aquatic Species. Waller, U. 2001. Tank culture and recirculating systems. Pages 99-127 in K. D. Black, editor. Environmental Impacts of Aquaculture. Sheffield Academic Press Ltd., Sheffield, UK. Watanabe, W. O., T. M. Losordo, K. Fitzsimmons, and F. Hanley. 2002. Tilapia production systems in the Americas: Technological advances, trends, and challenges. Reviews in Fisheries Science 10:465-498.
38 Seafood Watch® Farmed Tilapia Report May 16, 2006
Appendices
Appendix I. Assessment of Elite Aquaculture Ltd Farmed Tilapia
Elite Aquaculture Ltd Farmed Tilapia
Oreochromis niloticus
Guangxi Province, China
December 23, 2009
Peter Bridson Aquaculture Research Manager
39 Seafood Watch® Farmed Tilapia Report May 16, 2006
Executive Summary
In contrast to the overall Seafood Watch farmed tilapia report, which covers China on a country- wide basis, this appendix provides a farm-specific report on Elite Aquaculture Co Ltd (Elite) in southeast China, compiled as part of a pilot project for Seafood Watch’s Major Buyer partnership program.
During the past several years, Seafood Watch has built partnerships with two of the largest companies in the contract foodservice business. By focusing on collaborating with and supporting these companies, the Monterey Bay Aquarium can leverage their partners’ vendor relationships to help create change further down the seafood supply chain and effectively expand the reach and impact of their work significantly.
This pilot project at Elite was conducted after a request from one of these partners for the purpose of testing the ability to work with their specific supply chain to identify and procure more sustainable sources of seafood at the farm (rather than country) level.
Elite is a large vertically integrated tilapia farm producing 6,000 tons and 3,000 tons respectively from cage and pond production sites each year. The focus of this report is the cage-farming site certified to the standards of the Global Aquaculture Alliance’s Best Aquaculture Practice (BAP) and located in the Xiaojiang Reservoir in Guangxi province. The reservoir is man-made and therefore is not considered an area of high conservation concern.
Due to the intensity of the farming operation, the tilapia (when grown at low stocking densities) are dependent on formulated feed. The feed conversion ratio (1.6–1.8:1) is relatively high for tilapia, but due to a low level (7.5%) of Peruvian anchovy fishmeal in the feed, the wild-fish-in to farmed-fish-out conversion ratio is approximately 0.6, which is a ‘Low concern’ according to Seafood Watch criteria and the same as the countrywide ranking.
The 6,000 cages are of basic construction and susceptible to both significant-event and trickle losses (escapes) of fish. Free-living tilapia were not present in the reservoir before the farming operation began but can now be found, and the potential exists for feral populations to become established in upstream or downstream water courses. In line with broader concerns for the production of non-native tilapia in specific water courses in China, Elite receives the same ‘High concern’ ranking as the overall Seafood Watch tilapia report.
Tilapia are relatively resistant to disease and parasite outbreaks. Although there is no evidence of disease or parasite amplification or retransmission to date at Elite, and the man-made nature of the reservoir blurs the definition of ‘wild-stock’, cage culture carries a high potential risk for pathogen and parasite transfer from farmed to wild stocks. Therefore Elite’s farm must be ranked a ‘Moderate concern’ according to Seafood Watch criteria.
The large scale and intensity of production at Elite combined with the open nature of the cage farming system results in substantial nutrient loss from the farm, which would be expected to have a significant impact on the reservoir’s nutrient status. Certification to the BAP level requires significant water quality monitoring and compliance with set standards. The man-made
40 Seafood Watch® Farmed Tilapia Report May 16, 2006
nature of the reservoir and the lack of diverse habitats indicate that the risk of habitat damage or other negative impacts from pollution is probably low. However, the farm still represents a significant source of untreated and un-utilized effluent, and according to Seafood Watch criteria, this open farming system results in a ‘Moderate concern’ for risk of pollution and habitat effects.
The overall Seafood Watch tilapia report expresses serious concerns regarding the robustness and enforcement of Chinese environmental and aquaculture regulations. Despite speaking with government officials in China during the visit to Elite, the effectiveness of the regulatory structure governing aquaculture production in China and its enforcement (particularly the resources available for enforcement of the Ministry of Agriculture’s environmental regulations) are still unclear. Therefore, it is not possible to conclude that aquaculture operations in China have effective management unless they have been individually assessed.
Elite is focused on meeting the rigors of the export market and is increasingly vertically integrated (with a hatchery planned for 2010). In addition to the observed general farming operations, Elite maintains the sampling and other documentary records necessary for BAP certification. With the benefit of Seafood Watch’s farm-level visit, Elite appears to be a very well managed operation on a day-to-day basis. However, farm management is not effective at preventing escapes or at utilizing nutrients lost to the environment in the farm’s effluent—two key impact categories. Therefore, Elite’s management effectiveness ranks overall as a ‘Moderate concern’ according to Seafood Watch criteria.
In comparison to the overall Seafood Watch tilapia report, Elite receives the same rankings as general Chinese production for all but one of the Seafood Watch criteria—Management Effectiveness. Due to concerns about enforcement and the robustness of Chinese aquaculture and environmental regulations, China overall receives a ‘High concern’ ranking for management effectiveness. The farm-level visit to Elite confirmed that the farm is generally well managed and worthy of the improved ‘Moderate concern’ management effectiveness ranking.
Therefore, with only one red ‘High concern’ ranking (compared to two for China on a country- wide basis), tilapia produced at Elite’s cage site is ranked as a ‘Good Alternative’ overall according to Seafood Watch criteria.
Although certification to the Global Aquaculture Alliance’s Best Aquaculture Practices standards (GAA BAP) is not a factor in this Seafood Watch recommendation, the product identified within this report can be distinguished in the marketplace by the 2-star BAP certification.
As farming practices and data change, Seafood Watch reserves the right, in its sole and absolute discretion, to review, revise, or amend the contents of this report and associated recommendations at any time to reflect this new information.
41 Seafood Watch® Farmed Tilapia Report May 16, 2006
Table of Sustainability Ranks
Conservation Concern Sustainability Criteria Low Moderate High Critical Use of Marine Resources √ Risk of Escaped Fish to Wild
Stocks √ Risk of Disease and Parasite
Transfer to Wild Stocks √ Risk of Pollution and Habitat Effects √ Management Effectiveness √
About the Overall Seafood Recommendation: • A species receives a recommendation of “Best Choice” if: 1) It has three or more green criteria and the remaining criteria are not red.
• A species receives a recommendation of “Good Alternative” if: 1) Criteria “average” to yellow 2) There are four green criteria and one red criterion.
• A species receives a recommendation of “Avoid” if: 1) It has a total of two or more red criteria 2) It has one or more Critical Conservation Concerns.
Overall Seafood Recommendation:
Best Choice Good Alternative Avoid
42 Seafood Watch® Farmed Tilapia Report May 16, 2006
Introduction
Elite is an integrated aquaculture company operating: • A tilapia farm (cage and pond production sites), • A feed mill, and • A processing/packing facility. A hatchery is planned to be operational in 2010.
The focus of this report is on the cage production facility at Xiaojiang Reservoir in Guangxi Province, southeast China. The Xiaojiang site produces 6,000 tons of whole fish per year. With approximately 80% of China’s tilapia production coming from ponds, cage production sites such as this are in the minority. The tilapia produced is a hybrid of Oreochromis niloticus strains.
The site—Xiaojiang Reservoir Xiaojiang Reservoir is approximately a 2.5-hour drive inland from Behai in the Hepu County of Guangxi province. The reservoir is man-made and was constructed in the 1950s for hydro- electricity. Approximately 23 miles long, its total area is approximately 10,000 acres. The farm occupies approximately 2% of the reservoir surface area. The surrounding hills and islands are planted with commercial forests. Elite has an exclusive contract with the reservoir administration, meaning that no other companies are allowed to conduct aquaculture in the reservoir.
Figure 1 – Harvested cages next to the dam
The site—production Elite operates 6,000 small tilapia cages in the reservoir. The cages are of basic construction—a welded metal frame with simple flotation supporting suspended nets whose tops are
43 Seafood Watch® Farmed Tilapia Report May 16, 2006
approximately 30 cm above the water surface. Cage size is approximately 4–5 m x 4 m x 3 m deep. Each cage produces about 1,000 kg of tilapia per year.
The cages are moored together in rafts of about 40. Many cage-rafts have a floating feed store attached to one end.
Figure 2 – Cages connected together in rafts.
Figure 3 – Feed storage barge attached to cages.
Fry (all male) are stocked into cages from an independent hatchery at a size of 5 g and fed on eel powder until they are large enough to eat pelletized feeds. Elite plans to start supplying its own fry in 2010.
44 Seafood Watch® Farmed Tilapia Report May 16, 2006
Ongoing feeds are produced at Elite’s feed mill in Behai and transported by truck to the reservoir. Feed is hand-distributed by workers on each cage block.
Figure 4 –Feeding. Other cage units can be seen in the background
At harvest, the cages are towed down the reservoir to the dam. The nets are lifted and the fish hoisted by bucket into live-transport containers (Figures 5 and 6) and driven by truck (at high densities) to the processing factory (4-5 hours away).
Figure 5 – Harvesting presents a high risk of escape for individual fish or larger numbers.
45 Seafood Watch® Farmed Tilapia Report May 16, 2006
Figure 6 – Transferring fish to live-transport containers on truck.
Scope of the analysis and the ensuing recommendation: On a country-wide basis, China has a ‘Red – Avoid’ Seafood Watch ranking for farmed tilapia, and this report represents efforts by Seafood Watch ‘Major Buyer’ partners to identify better ‘Good Alternative’ producers within the country. This is a farm-specific report and is based on a visit to Elite Tilapia’s BAP-certified (Global Aquaculture Alliance’s Best Aquaculture Practices standard) cage-production site at Xiaojiang Reservoir in June 2009.
Analysis of Seafood Watch® Sustainability Criteria for Farm-Raised Species
Criterion 1: Use of Marine Resources
At low intensities, tilapia can be produced in fertilized ponds with low or even zero use of compound feeds. Intensive cage production does not take advantage of this ability. While a very small amount of natural feed may originate from within the reservoir, the fish rely overwhelmingly on pelletized feeds from Elite’s feed plant in Behai, which produces about 16,000 tons of feed per year.
The fishmeal (FM) content of the feed varies throughout the production cycle. For small sizes, FM content is 12%, which then drops to 9% and 6% in the intermediate and final growout feeds. Fish oil is not used in Elite’s feeds; the fishmeal is from Peruvian anchovy.
46 Seafood Watch® Farmed Tilapia Report May 16, 2006
According to the farm’s data, the feed conversion ratio (FCR) is 1.6–1.8. A rough calculation of 16,000 tons of feed divided by 9,000 tons of whole tilapia produced confirms this range with an economic FCR (eFCR) value of 1.78
Wild fish in to farmed fish out ratio (WI:FO)
Fishmeal inclusion rates vary though the production cycle, but the majority of feed is used for the larger growout sizes. Using the FM content values above, an estimated FM inclusion rate of 7.5% is representative of the entire production cycle. When fishmeal yield from Peruvian anchovy is taken to be 4.5 (in line with SFW reports) and an eFCR value of 1.78 is used, then
WI:FO = 4.5 x 0.075 x 1.78 = 0.6
As a sensitivity check on the FM inclusion rate, if the estimated average fishmeal content were as high as 12%, the WI:FO value for the whole cycle would still be less than 1.1 and therefore in the ‘low’ range.
While this WI:FO value (0.6) is in the low range (0-1.1), tilapia have a relatively low fillet yield ranging from 33% to 29% depending on the depth of the skinning technique (deep or super-deep skinning removes the red/brown muscle under the skin and provides a pure white meat fillet). Therefore, the real WI:FO value is a little lower compared to fish with higher fillet yields (e.g., salmon at 45–50%).
Using an alternate calculation, the estimated average FM inclusion value of 7.5% for 16,000 tons of feed means (assuming a 4.5% conversion rate for Peruvian anchovy) that Elite uses the equivalent of approximately 5,400 tons of Peruvian Anchovy to produce 9,000 tons of tilapia (cage and pond production combined), which confirms a WI:FO value of 0.6.
Hatchery All fingerlings are supplied by hatcheries and there is no impact to marine (or freshwater) resources for fingerlings or broodstock.
Synthesis Despite the relatively high FCR at Elite, the low fishmeal inclusion rates and the use of hatcheries results in a ‘Low’ use of marine resources. This is the same ranking as the overall Seafood Watch Farmed Tilapia report for all countries.
Use of Marine Resources Rank:
Low Moderate High
47 Seafood Watch® Farmed Tilapia Report May 16, 2006
Criterion 2: Risk of Escaped Fish to Wild Stocks
Free-living tilapia were not present in Xiaojiang Reservoir before Elite began farming but can now be found, almost certainly due to escapes from the farm. The cage farming system is susceptible to both catastrophic losses and ongoing ‘trickle’ losses during routine farm operations. The risk of escaping fry from breeding within the farm (a common problem in pond- based tilapia farms) is not considered a significant risk here since the tilapia have no access to the reservoir substrate in which to dig a nest.
Due to the size of the reservoir, the cages are at risk of damage from severe weather. In one storm, 200 cages were damaged resulting in the loss of a large quantity of fish. Trickle losses are likely during several routine operations such as net changing and harvest. Individual fish were observed to escape during the visit while the fish were being harvested and transferred to live- transport containers.
Although a non-native species in China, tilapia have become established in many natural water bodies. According to Qiuming and Yi (2004): The first tilapia species introduced to mainland China is Mozambique tilapia (Oreochromis mossambicus) from Vietnam in 1957. Since then, several tilapia species such as blue tilapia (O. aureus) and different strains of Nile tilapia (O. niloticus) have been introduced to China from different places. Tilapia culture in China started in the early 1960s, but was not popular until the early 1980s. Since then, tilapia culture has been expanded rapidly in response to the introduction of new strains.
The potential for further ecological damage from new introductions or ongoing escapes remains. For example, according to Senanan and Bart (2009): New introductions of tilapias for aquaculture and enhanced fisheries into areas with no captive or free-living tilapias need careful consideration, and new introductions of tilapias for aquaculture and enhanced fisheries should not be made into areas with high conservation value; or into areas with no existing free-living populations of tilapias.
Despite several decades of discussion among ecologists, tilapia that escape from farms and aquaculture research and development establishments remain a concern to suppliers and consumers as well as to environmentalists (Senanan and Bart, 2009).
The risk of fish escape from a particular farming system depends on farm location, the engineering design and construction of the farm, and maintenance and farm management by the farm operators. The number of possible escaped fish may also depend on the intensity of production, ranging from low intensity (integrated aquaculture, extensive) to high intensity (large commercial monoculture) production systems (Senanan and Bart, 2009). Therefore, Elite’s intensive cage site in a large reservoir using basic cages carries a high risk of escapes.
Escaped tilapia that become established as feral populations can cause adverse ecological impacts through competition with wild fish for territory, especially for feeding and breeding sites, and can alter habitats by grazing vegetation, releasing nutrients in excreta and building nests. The cultured tilapia at Elite are all male due to a methyl-testosterone hormone
48 Seafood Watch® Farmed Tilapia Report May 16, 2006
treatment at the hatchery. This process is not 100% effective and some females do exist in the population. Although the dominance of male fish would reduce the rate of establishment in the wild, the presence of some females means that it is technically possible for self-sustaining populations to establish rapidly in suitable locations.
The impacts of escape that may be most pertinent for tilapia include competition for food and space for breeding, spread of pathogens, and changes in the physical or chemical properties of the water bodies (Senanan and Bart, 2009). However, in Xiaojiang Reservoir these impacts are likely to be small. After construction, the lake was stocked with fish that now support a small fishery by local villagers; escaped tilapia are more likely to enhance this fishery than reduce it. Tilapia are not predatory, so an adverse ecological impact due to tilapia predation on other biota is unlikely.
Since the reservoir is man-made, it is unlikely to be considered an area of high conservation value, yet the potential for escaped tilapia to enter upstream or downstream watercourses exists (although downstream survival through the hydro-electric station or via other routes is unknown).
The potential for a negative impact (on the basis of the potential impacts described above) beyond the reservoir must be considered, but positive impacts are also possible (Senanan and Bart, 2009). Potential positive impacts include increases in species diversity and productivity, although these are considered mainly in areas of the Asia-Pacific region where native species with similar characteristics to tilapia are limited.
Considering the above information, assessing the conservation risk of Elite’s operation is not straightforward. A risk characterization matrix between the probability of an escape event occurring and the severity of the resulting impact shows a high probability of escape from Elite’s operation but most likely a low impact severity. The default position is that escapes are considered a serious concern unless there are studies or evidence that prove otherwise.
According to Seafood Watch criteria (see Annex 1), if a species escapes ‘Regularly and often in open systems’ and is ‘Non-native and not yet fully established’ this criteria ranks as ‘Red’. Since tilapia were not present in Xiaojiang Reservoir before Elite began farming, a strict assessment makes ‘Red’ the appropriate ranking. However, it could be argued that the impacts on wild stocks in the man-made reservoir are low and tilapia are now widely established in China; therefore, rather than ‘Non-native and not yet fully established’, this factor could be ranked ‘Non-native but historically widely established’, resulting in a ‘Yellow’ ranking for this criterion. This view does not, however, consider the potential for negative impacts beyond the reservoir, and these must also be taken into account.
Synthesis Considering the lack of free-living tilapia in Xiaojiang Reservoir and the surrounding area before Elite began operations, tilapia are considered to be ‘Non-native and not yet fully established’ according to Seafood Watch criteria. When combined with the high risk of escapes from the cage-culture system, the unknown impacts on upstream and downstream habitats in the water catchment area and the lack of proof of no negative impacts, these criteria rank as a high concern by Seafood Watch guidelines and match that of China as a whole.
49 Seafood Watch® Farmed Tilapia Report May 16, 2006
Risk of Escaped Fish to Wild Stocks Rank:
Low Moderate High Critical
Criterion 3: Risk of Disease and Parasite Transfer to Wild Stocks
According to Senanan and Bart (2009), escaped tilapia can introduce and spread a wide range of pathogens and parasites to wild fish and other farmed fish. Although disease outbreaks have been reported for tilapia in other farming areas outside of China (Jack Morales, Sustainable Fisheries Partnership, pers. comm.), tilapia are relatively resistant to disease in comparison to most aquaculture species. With the cage production method, there is clearly an opportunity for any disease on the farm to be transferred to any surrounding fish populations, and therefore the risk is high. At Elite, however, there is little if any evidence of disease or parasite problems in the cultured stock. As a result, or due to the difficulty of demonstrating it, there appears to be little risk of disease or parasite amplification or retransmission beyond the farm, or of introducing or translocating novel diseases or parasites. Based on the difficulty of demonstrating disease or parasite transfer, these factors are ranked ‘Unknown’ as a precaution.
In addition, the man-made nature of the reservoir and the vague definition of ‘wild stocks’ in this context combined with the unknown potential for transmission to water bodies beyond the reservoir make a clear assessment challenging.
The introduction of disease or parasites to the reservoir by way of infected fry from an external hatchery is possible, but with little evidence of disease during growout production, this risk seems low.
Synthesis Although there is no evidence of disease or parasite amplification and retransmission to date at Elite, and the man-made nature of the reservoir blurs the definition of ‘wild stocks’, cage culture carries an inherently high potential risk of pathogen or parasite transfer from farmed to wild stocks, and therefore Elite’s farm must be ranked a ‘Moderate’ risk to wild stocks according to Seafood Watch criteria. This is the same ranking as the overall Seafood Watch Farmed Tilapia Report for all countries except the US where tilapia are grown in closed production systems.
Risk of Disease Transfer to Wild Stocks Rank:
Low Moderate High Critical
50 Seafood Watch® Farmed Tilapia Report May 16, 2006
Criterion 4: Risk of Pollution and Habitat Effects
First impressions of Elite’s reservoir farm site are of large-scale intensive production with rafts of cages spread over a large area. In reality, the cages occupy only 2% of the reservoir surface area, and while it would be expected that they have an impact on the immediate local area, sampling data shows that despite elevated nutrient (and chlorophyll) levels near the cages, the effects are minimal in areas of the reservoir distant from the cages (500 m required sampling for BAP certification).
The open nature of the cage farming system means that there is no treatment of the farm’s soluble and particulate effluent wastes from fish feces and uneaten feed. The farm relies on the carrying capacity of the reservoir to maintain adequate water quality for the farming operation. Since the nutrients are originally sourced from distant locations and transported by truck to the reservoir in the form of pellet feed, this loss of nutrients from the farm is inefficient.
Water quality on the farm is checked by workers regularly (typically daily) and every three months by the local Fishery Bureau as part of the fishery license. Samples are only taken at the surface since deep-water sampling is more complex. Benthic impacts are not assessed due to the complexities of sampling.
The man-made nature of the reservoir is also a factor here and clearly dictates the habitats present in the area. Although the reservoir is roughly fifty years old, there appears to be relatively little wildlife in the area at risk of impact. There are stocks of fish in the reservoir that support a small local fishery, but these are unlikely to be negatively impacted by the farm and may even benefit from the increased nutrient input and primary productivity.
According to the BAP certification, the hydraulic retention time of the reservoir is low with approximately 80% of the water volume of the reservoir being exchanged each year. The water downstream of the reservoir is used for irrigation (but not exclusively).
Synthesis Due to the large scale of production, the intensity of the site and the open nature of the cage farming system, there is substantial nutrient loss from the farm, which would be expected to have a significant impact on the reservoir’s nutrient status. However, the farm meets the water quality requirements of the BAP certification (available at www.aquaculturecertification.org), and the man-made nature of the reservoir and lack of diverse habitats indicate that the risk of habitat damage or other negative impacts from pollution is probably low. In addition, the reservoir is used for irrigation, and any elevated nutrient levels would be used to fertilize crops downstream. According to Seafood Watch criteria, the lack of effluent treatment in this open farming system results in a ‘Moderate’ risk for pollution and habitat effects. This is the same ranking as China as a whole.
51 Seafood Watch® Farmed Tilapia Report May 16, 2006
Risk of Pollution and Habitat Effects Rank:
Low Moderate High
Criterion 5: Effectiveness of the Management Regime
Despite many conversations with farmers, processors and fishery officials in China, the regulatory structure and mechanisms for its enforcement are still unclear. Federal, state and local laws do apply, but anecdotal evidence suggests their effectiveness and level of enforcement are unknown.
The regulatory structure is housed within China’s Ministry of Agriculture. The China Inspection and Quarantine (CIQ) bureau is the department responsible (comparable to the US Food and Drug Administration), which closely regulates the producers exporting tilapia to protect the international market and operates in accordance with the Certification and Accreditation Administration of China (CNCA). Much of CIQ’s governance relates to food safety requirements. Enforcement of environmental regulations by the Ministry of Agriculture appears to be considerably under-staffed and is therefore considered to be ineffective.
For example, in common with the majority of tilapia farms in China (and elsewhere), Elite purchases all-male fry from a hatchery that uses the banned hormone methyl-testosterone (MT). Fishery Bureau officials report that this practice does not take place in China, but the use of MT is clearly widespread. This casts further doubt on enforcement by the Chinese authorities. Concerns over the effectiveness and enforcement of regulations in China resulted in a ‘High concern’ ranking in the overall Seafood Watch report for China’s management effectiveness.
With the benefit of a farm-level visit to Elite and the ability to interview the managers and inspect documentary records, the farm and its daily operations appear well managed. The farm has detailed production records available, partly resulting from the requirements of certification to Best Aquaculture Practice standards (although records are also available from prior to BAP certification), in addition to documentary evidence of compliance with siting and water quality regulations.
Elite has documents demonstrating their sole right to use Xiaojiang Reservoir and their water quality data demonstrate that the farm operation, although appearing relatively large and intense, is only moderately affecting the nutrient dynamics of the reservoir. The monitoring of the food safety aspects of export-focused farms by CIQ does appear robust and is considered to be effective in preventing the use of antibiotics and other banned therapeutics, a conclusion supported by Seafood Watch’s on-farm observations.
Despite the apparent effectiveness of Elite’s management, neither the farm’s management nor the requirements of the Best Aquaculture Practices standards prevent (or require a precautionary approach to) the significant potential for escapes from the cage production system or account for the significant amount of nutrient wastes lost to the environment. Better management practices (BMPs) are in place to prevent escapes (both at the farm level and incorporated into the Best
52 Seafood Watch® Farmed Tilapia Report May 16, 2006
Aquaculture Practices standards), but BMPs are not generally sufficient to prevent escapes, and their effectiveness at Elite is clearly in doubt.
The use of a precautionary principle to control expansion of the industry is difficult to assess at the farm level but is considered to be partly addressed in Elite’s case by their sole control over production in Xiaojiang Reservoir and their effective management in controlling production volumes according to the maintenance of satisfactory water quality.
Synthesis Elite appears to be a very well managed farm. It is focuses on producing for the rigorous export market, is increasingly vertically integrated (with a hatchery planned for 2010) and maintains the detailed sampling and other documentary records of effective farm management necessary for BAP certification.
In these respects, the management regime at Elite is considered to be good, yet the management is not effective at preventing escapes or in utilizing nutrients lost to the environment in the farm’s effluent—two key impact categories among the Seafood Watch criteria.
Due to the concerns expressed above and in the Seafood Watch Farmed Tilapia report, China as a whole receives a ‘High Concern’ ranking for management effectiveness. The farm-level visit to Elite enabled direct observation of their more effective management. As a result, Elite’s management effectiveness is ranked as ‘Moderate’.
Effectiveness of Management Rank:
Low Moderate High
Overall Evaluation and Seafood Ranking
Table of Sustainability Ranks
Conservation Concern Sustainability Criteria Low Moderate High Critical Use of Marine Resources √ Risk of Escaped Fish to Wild
Stocks √ Risk of Disease and Parasite
Transfer to Wild Stocks √ Risk of Pollution and Habitat Effects √ Management Effectiveness √
53 Seafood Watch® Farmed Tilapia Report May 16, 2006
About the Overall Seafood Recommendation: • A species receives a recommendation of “Best Choice” if: 1) It has three or more green criteria and the remaining criteria are not red.
• A species receives a recommendation of “Good Alternative” if: 1) Criteria “average” to yellow 2) There are four green criteria and one red criterion
• A species receives a recommendation of “Avoid” if: 1) It has a total of two or more red criteria 2) It has one or more Critical Conservation Concerns.
Overall Seafood Recommendation:
Best Choice Good Alternative Avoid
Acknowledgements Seafood Watch would like to thank the management and staff of Elite Aquaculture for opening their farm and records to inspection as well as Jack Morales (Sustainable Fisheries Partnership) and Irene Tetreault Miranda (author of Seafood Wacth Farmed Tilapia report) for reviewing this report.
Scientific review does not constitute an endorsement of the Seafood Watch® program, or its seafood recommendations, on the part of the reviewing scientists. Seafood Watch® is solely responsible for the conclusions reached in this report.
References Senanan, W., Bart, A. 2009. The Potential Risks from Farm Escaped Tilapias. Sustainable Fisheries Partnership. http://media.sustainablefish.org/Tilapia_escapes_WP.pdf
Qiuming, L.,Yang, Y. 2004. Tilapia Culture in Mainland China. Paper presented at the Sixth International Symposium on Tilapia in Aquaculture, 12–16 September 2004. Philippine International Convention Center, Manila, Philippines.
54 Seafood Watch® Farmed Tilapia Report May 16, 2006
Appendix II. Aquaculture Evaluation of Elite Aquaculture Ltd Farmed Tilapia
Species: Tilapia Region: Elite - China
Analyst: Peter Bridson Date: June 2009
Seafood Watch™ defines sustainable seafood as from sources, whether fished or farmed, that can maintain or increase production into the long-term without jeopardizing the structure or function of affected ecosystems.
The following guiding principles illustrate the qualities that aquaculture operations must possess to be considered sustainable by the Seafood Watch program. Sustainable aquaculture: • uses less wild caught fish (in the form of fish meal and fish oil) than it produces in the form of edible marine fish protein, and thus provides net protein gains for society; • does not pose a substantial risk of deleterious effects on wild fish stocks through the escape of farmed fish1; • does not pose a substantial risk of deleterious effects on wild fish stocks through the amplification, retransmission or introduction of disease or parasites; • employs methods to treat and reduce the discharge of organic waste and other potential contaminants so that the resulting discharge does not adversely affect the surrounding ecosystem; and • implements and enforces all local, national and international laws and customs and utilizes a precautionary approach (which favors conservation of the environment in the face of irreversible environmental risks) for daily operations and industry expansion.
Seafood Watch has developed a set of five sustainability criteria, corresponding to these guiding principles, to evaluate aquaculture operations for the purpose of developing a seafood recommendation for consumers and businesses. These criteria are: 1. Use of marine resources 2. Risk of escapes to wild stocks 3. Risk of disease and parasite transfer to wild stocks 4. Risk of pollution and habitat effects 5. Effectiveness of the management regime
Each criterion includes: • Primary factors to evaluate and rank • Secondary factors to evaluate and rank • Evaluation guidelines2 to synthesize these factors • A resulting rank for that criterion
1 “Fish” is used throughout this document to refer to finfish, shellfish and other farmed invertebrates. 2 Evaluation Guidelines throughout this document reflect common combinations of primary and secondary factors that result in a given level of conservation concern. Not all possible combinations are shown – other combinations should be matched as closely as possible to the existing guidelines.
55 Seafood Watch® Farmed Tilapia Report May 16, 2006
Once a rank has been assigned to each criterion, an overall seafood recommendation for the type of aquaculture in question is developed based on additional evaluation guidelines. The ranks for each criterion, and the resulting overall seafood recommendation, are summarized in a table.
Criteria ranks and the overall recommendation are color-coded to correspond to the categories on the Seafood Watch pocket guide:
Best Choices/Green: Consumers are strongly encouraged to purchase seafood in this category. The aquaculture source is sustainable as defined by Seafood Watch.
Good Alternatives/Yellow: Consumers are encouraged to purchase seafood in this category, as they are better choices than seafood from the Avoid category. However, there are some concerns with how this species is farmed and thus it does not demonstrate all of the qualities of sustainable aquaculture as defined by Seafood Watch.
Avoid/Red: Consumers are encouraged to avoid seafood from this category, at least for now. Species in this category do not demonstrate enough qualities to be defined as sustainable by Seafood Watch.
56 Seafood Watch® Farmed Tilapia Report May 16, 2006
CRITERION 1: USE OF MARINE RESOURCES
Guiding Principle: To conserve ocean resources and provide net protein gains for society, aquaculture operations should use less wild-caught fish (in the form of fish meal and fish oil) than they produce in the form of edible marine fish protein.
Feed Use Components to Evaluate A) Yield Rate: Amount of wild-caught fish (excluding fishery by-products) used to create fish meal and fish oil (ton/ton): ¾ Wild Fish: Fish Meal; Enter ratio = 4.5 [i.e. value = 4.5:1 from Tyedmers (2000)3] ¾ Wild Fish: Fish Oil; Enter ratio: n/a [i.e. value = 8.3:1 from Tyedmers (2000)]
B) Inclusion rate of fish meal, fish oil, and other marine resources in feed (%): ¾ Fish Meal; Enter % = 7.5% ¾ Fish Oil; Enter % = n/a
C) Efficiency of Feed Use: Known or estimated average economic Feed Conversion Ratio (FCR = dry feed:wet fish) in grow-out operations: ¾ Enter FCR here = 1.78
Wild Input:Farmed Output Ratio (WI:FO) Calculate and enter the larger of two resultant values:
¾ Meal: [Yield Rate]meal x [Inclusion rate]meal x [FCR] = 0.6
¾ Oil: [Yield Rate]oil x [Inclusion rate]oil x [FCR] = n/a ¾ WI:FO = 0.6
Primary Factor (WI:FO) Estimated wild fish used to produce farmed fish (ton/ton, from above): ¾ Low Use of Marine Resources (WI:FO = 0 - 1.1) OR supplemental feed not used ¾ Moderate Use of Marine Resources (WI:FO = 1.1 - 2.0) ¾ Extensive Use of Marine Resources (WI:FO > 2.0)
3 Tyedmers (2000): Salmon and sustainability: The biophysical cost of producing salmon through the commercial salmon fishery and the intensive salmon culture industry. PhD Thesis. The University of British Columbia. 272 pages.
57 Seafood Watch® Farmed Tilapia Report May 16, 2006
Secondary Factors Stock status of the reduction fishery used for feed for the farmed species:
¾ At or above BMSY (> 100%)
¾ Moderately below BMSY (50 - 100%) OR Unknown
¾ Substantially below BMSY (e.g. < 50%) OR Overfished OR Overfishing is occurring OR fishery is unregulated ¾ Not applicable because supplemental feed not used
Source of stock for the farmed species: ¾ Stock from closed life cycle hatchery OR wild caught and intensity of collection clearly does not result in depletion of brood stock, wild juveniles or associated non-target organisms ¾ Wild caught and collection has the potential to impact brood stock, wild juveniles or associated non-target organisms ¾ Wild caught and intensity of collection clearly results in depletion of brood stock, wild juveniles, or associated non-target organisms
58 Seafood Watch® Farmed Tilapia Report May 16, 2006
Evaluation Guidelines
Use of marine resources is “Low” when WI:FO is between 0.0 and 1.1.
Use of marine resources is “Moderate” when WI:FO is between 1.1 and 2.0.
Use of marine resources is “Extensive” when: 1. WI:FO is greater than 2.0 2. Source of stock for the farmed species is ranked red 3. Stock status of the reduction fishery is ranked red
Use of marine resources is deemed to be a Critical Conservation Concern and a species is ranked Avoid, regardless of other criteria, if: 1. WI:FO is greater than 2.0 AND the source of seed stock is ranked red. 2. WI:FO is greater than 2.0 AND the stock status of the reduction fishery is ranked red
Conservation Concern: Use of Marine Resources
Low (Low Use of Marine Resources) Moderate (Moderate Use of Marine Resources) High (Extensive Use of Marine Resources) Critical Use of Marine Resources
59 Seafood Watch® Farmed Tilapia Report May 16, 2006
CRITERION 2: RISK OF ESCAPED FISH TO WILD STOCKS
Guiding Principle: Sustainable aquaculture operations pose no substantial risk of deleterious effects to wild fish stocks through the escape of farmed fish.
Primary Factors to evaluate
Evidence that farmed fish regularly escape to the surrounding environment ¾ Rarely if system is open OR never because system is closed ¾ Infrequently if system is open OR Unknown ¾ Regularly and often in open systems
Status of escaping farmed fish to the surrounding environment ¾ Native and genetically and ecologically similar to wild stocks OR survival and/or reproductive capability of escaping farmed species is known to be naturally zero or is zero because of sterility, polyploidy or similar technologies ¾ Non-native but historically widely established OR Unknown ¾ Non-native (including genetically modified organisms) and not yet fully established OR native and genetically or ecologically distinct from wild stocks
Secondary Factors to evaluate
Where escaping fish is non-native – Evidence of the establishment of self-sustaining feral stocks ¾ Studies show no evidence of establishment to date ¾ Establishment is probable on theoretical grounds OR Unknown ¾ Empirical evidence of establishment
Where escaping fish is native – Evidence of genetic introgression through successful crossbreeding ¾ Studies show no evidence of introgression to date ¾ Introgression is likely on theoretical grounds OR Unknown ¾ Empirical evidence of introgression
Evidence of spawning disruption of wild fish ¾ Studies show no evidence of spawning disruption to date ¾ Spawning disruption is likely on theoretical grounds OR Unknown ¾ Empirical evidence of spawning disruption
60 Seafood Watch® Farmed Tilapia Report May 16, 2006
Evidence of competition with wild fish for limiting resources or habitats ¾ Studies show no evidence of competition to date ¾ Competition is likely on theoretical grounds OR Unknown ¾ Empirical evidence of competition
Stock status of affected wild fish
¾ At or above (> 100%) BMSY OR no affected wild fish
¾ Moderately below (50 – 100%) BMSY OR Unknown
¾ Substantially below BMSY (< 50%) OR Overfished OR “endangered”, “threatened” or “protected” under state, federal or international law
Evaluation Guidelines
A “Minor Risk” occurs when a species: 1) Never escapes because system is closed 2) Rarely escapes AND is native and genetically/ecologically similar. 3) Infrequently escapes AND survival is known to be nil.
A “Moderate Risk” occurs when the species: 1) Infrequently escapes AND is non-native and not yet fully established AND there is no evidence to date of negative interactions. 2) Regularly escapes AND native and genetically and ecologically similar to wild stocks or survival is known to be nil. 3) Is non-native but historically widely established.
A “Severe Risk” occurs when: 1) The two primary factors rank red AND one or more additional factor ranks red.
Risk of escapes is deemed to be a Critical Conservation Concern and a species is ranked Avoid, regardless of other criteria, when: 1) Escapes rank a “severe risk” AND the status of the affected wild fish also ranks red.
Conservation Concern: Risk of Escaped Fish to Wild Stocks Low (Minor Risk) Moderate (Moderate Risk) High (Severe Risk) Critical Risk
61 Seafood Watch® Farmed Tilapia Report May 16, 2006
CRITERION 3: RISK OF DISEASE AND PARASITE TRANSFER TO WILD STOCKS
Guiding Principle: Sustainable aquaculture operations pose little risk of deleterious effects to wild fish stocks through the amplification, retransmission or introduction of disease or parasites.
Primary Factors to evaluate
Risk of amplification and retransmission of disease or parasites to wild stocks ¾ Studies show no evidence of amplification or retransmission to date ¾ Likely risk of amplification or transmission on theoretical grounds OR Unknown ¾ Empirical evidence of amplification or retransmission
Risk of species introductions or translocations of novel disease/parasites to wild stocks ¾ Studies show no evidence of introductions or translocations to date ¾ Likely risk of introductions or translocations on theoretical grounds OR Unknown ¾ Empirical evidence of introductions or translocations
Secondary Factors to evaluate
Bio-safety risks inherent in operations ¾ Low risk: Closed systems with controls on effluent release ¾ Moderate risk: Infrequently discharged ponds or raceways OR Unknown ¾ High risk: Frequent water exchange OR open systems with water exchange to outside environment (e.g. nets, pens or cages)
Stock status of potentially affected wild fish
¾ At or above (> 100%) BMSY OR no affected wild fish
¾ Moderately below (50 – 100%) BMSY OR Unknown
¾ Substantially below BMSY (< 50%) OR Overfished OR “endangered”, “threatened” or “protected” under state, federal or international law
62 Seafood Watch® Farmed Tilapia Report May 16, 2006
Evaluation Guidelines
Risk of disease transfer is deemed “Minor” if: 1) Neither primary factor ranks red AND both secondary factors rank green. 2) Both primary factors rank green AND neither secondary factor ranks red
Risk of disease transfer is deemed to be “Moderate” if the ranks of the primary and secondary factors “average” to yellow.
Risk of disease transfer is deemed to be “Severe” if: 1) Either primary factor ranks red AND bio-safety risks are low or moderate. 2) Both primary factors rank yellow AND bio-safety risks are high AND stock status of the wild fish does not rank green.
Risk of disease transfer is deemed to be a Critical Conservation Concern and a species is ranked Avoid regardless of other criteria, if either primary factor ranks red AND stock status of the wild fish also ranks red.
Conservation Concern: Risk of Disease Transfer to Wild Stocks Low (Minor Risk) Moderate (Moderate Risk) High (Severe Risk) Critical Risk
63 Seafood Watch® Farmed Tilapia Report May 16, 2006
CRITERION 4: RISK OF POLLUTION AND HABITAT EFFECTS
Guiding Principle: Sustainable aquaculture operations employ methods to treat and reduce the discharge of organic effluent and other potential contaminants so that the resulting discharge and other habitat impacts do not adversely affect the integrity and function of the surrounding ecosystem.
Primary Factors to evaluate
PART A: Effluent Effects Effluent water treatment ¾ Effluent water substantially treated before discharge (e.g. recirculating system, settling ponds, or reconstructed wetlands) OR polyculture and integrated aquaculture used to recycle nutrients in open systems OR treatment not necessary because supplemental feed is not used ¾ Effluent water partially treated before discharge (e.g. infrequently flushed ponds) ¾ Effluent water not treated before discharge (e.g. open nets, pens or cages)
Evidence of substantial local (within 2 x the diameter of the site) effluent effects (including altered benthic communities, presence of signature species, modified redox potential, etc) ¾ Studies show no evidence of negative effects to date ¾ Likely risk of negative effects on theoretical grounds OR Unknown ¾ Empirical evidence of local effluent effects
Evidence of regional effluent effects (including harmful algal blooms, altered nutrient budgets, etc) ¾ Studies show no evidence of negative effects to date ¾ Likely risk of negative effects on theoretical grounds OR Unknown ¾ Empirical evidence of regional effluent effects
Extent of local or regional effluent effects ¾ Effects are in compliance with set standards ¾ Effects infrequently exceed set standards ¾ Effects regularly exceed set standards
PART B: Habitat Effects
64 Seafood Watch® Farmed Tilapia Report May 16, 2006
Potential to impact habitats: Location ¾ Operations in areas of low ecological sensitivity (e.g. land that is less susceptible to degradation, such as formerly used agriculture land or land previously developed) ¾ Operations in areas of moderate sensitivity (e.g. coastal and near-shore waters, rocky intertidal or subtidal zones, river or stream shorelines, offshore waters) ¾ Operations in areas of high ecological sensitivity (e.g. coastal wetlands, mangroves)
Potential to impact habitats: Extent of Operations ¾ Low density of fish/site or sites/area relative to flushing rate and carrying capacity in open systems OR closed systems ¾ Moderate densities of fish/site or sites/area relative to flushing rate and carrying capacity for open systems ¾ High density of fish/site or sites/area relative to flushing rate and carrying capacity for open systems
Evaluation Guidelines
Risk of pollution/habitat effects is “Low” if three or more factors rank green and none of the other factors are red.
Risk of pollution/habitat effects is “Moderate” if factors “average” to yellow.
Risk of pollution/habitat effects is “High” if three or more factors rank red.
No combination of ranks can result in a Critical Conservation Concern for Pollution and Habitat Effects.
Conservation Concern: Risk of Pollution and Habitat Effects Low (Low Risk) Moderate (Moderate Risk) High (High Risk)
65 Seafood Watch® Farmed Tilapia Report May 16, 2006
CRITERION 5: EFFECTIVENESS OF THE MANAGEMENT REGIME
Guiding Principle: The management regime of sustainable aquaculture operations respects all local, national and international laws and utilizes a precautionary approach, which favors the conservation of the environment, for daily operations and industry expansion.
Primary Factors to evaluate
Demonstrated application of existing federal, state and local laws to current aquaculture operations ¾ Yes, federal, state and local laws are applied ¾ Yes but concerns exist about effectiveness of laws or their application ¾ Laws not applied OR laws applied but clearly not effective
Use of licensing to control the location (siting), number, size and stocking density of farms ¾ Yes and deemed effective ¾ Yes but concerns exist about effectiveness ¾ No licensing OR licensing used but clearly not effective
Existence and effectiveness of “better management practices” for aquaculture operations, especially to reduce escaped fish ¾ Exist and deemed effective ¾ Exist but effectiveness is under debate OR Unknown ¾ Do not exist OR exist but clearly not effective
Existence and effectiveness of measures to prevent disease and to treat those outbreaks that do occur (e.g. vaccine program, pest management practices, fallowing of pens, retaining diseased water, etc.) ¾ Exist and deemed effective ¾ Exist but effectiveness is under debate OR Unknown ¾ Do not exist OR exist but clearly not effective
Existence of regulations for therapeutants, including their release into the environment, such as antibiotics, biocides, and herbicides ¾ Exist and deemed effective OR no therapeutants used ¾ Exist but effectiveness is under debate, or Unknown ¾ Not regulated OR poorly regulated and/or enforced
Use and effect of predator controls (e.g. for birds and marine mammals) in farming
66 Seafood Watch® Farmed Tilapia Report May 16, 2006 operations ¾ Predator controls are not used OR predator deterrents are used but are benign ¾ Predator controls used with limited mortality or displacement effects ¾ Predator controls used with high mortality or displacement effects
Existence and effectiveness of policies and incentives, utilizing a precautionary approach (including ecosystem studies of potential cumulative impacts) against irreversible risks, to guide expansion of the aquaculture industry ¾ Exist and are deemed effective ¾ Exist but effectiveness is under debate ¾ Do not exist OR exist but are clearly ineffective
Evaluation Guidelines
Management is “Highly Effective” if four or more factors rank green and none of the other factors rank red.
Management is “Moderately Effective” if the factors “average” to yellow.
Management is deemed to be “Ineffective” if three or more factors rank red.
No combination of factors can result in a Critical Conservation Concern for Effectiveness of Management.
Conservation Concern: Effectiveness of the Management Regime
Low (Highly Effective) Moderate (Moderately Effective) High (Ineffective)
67 Seafood Watch® Farmed Tilapia Report May 16, 2006
Overall Seafood Recommendation
Overall Guiding Principle: Sustainable farm-raised seafood is grown and harvested in ways can maintain or increase production in the long-term without jeopardizing the structure or function of affected ecosystems.
Evaluation Guidelines
A species receives a recommendation of “Best Choice” if: 1) It has three or more green criteria and the remaining criteria are not red.
A species receives a recommendation of “Good Alternative” if: 1) Criteria “average” to yellow 2) There are four green criteria and one red criteria
A species receives a recommendation of “Avoid” if: 1) It has a total of two or more red criteria 2) It has one or more Critical Conservation Concerns.
Summary of Criteria Ranks Conservation Concern
Sustainability Criteria Low Moderate High Critical
Use of Marine Resources
Risk of Escapes to Wild Stocks
Risk of Disease/Parasite Transfer to Wild Stocks
Risk of Pollution and Habitat Effects
Effectiveness of Management
Overall Seafood Recommendation
Best Choice
Good Alternative
Avoid
68