Seafood Assessment

Rainbow Trout Oncorhynchus mykiss

Image Credit: Fisheries and Oceans Canada

January 2008

Laura Winter Gintas Kamaitis Rainbow Trout January 2008

About Sea Choice and Seafood Assessments

The Sea Choice program evaluates the ecological sustainability of wild-caught and farmed seafood commonly found in the Canadian marketplace. Sea Choice 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. Sea Choice makes its science-based recommendations available to the public in the form of a pocket guide, Canada’s Seafood Guide, that can be downloaded from the Internet (www.seachoice.org) or obtained from the Sea Choice program directly by emailing a request to us. The program’s goals are to raise awareness of important ocean conservation issues and empower Canadian seafood consumers and businesses to make choices for healthy oceans. Each sustainability recommendation on Canada’s Seafood Guide is supported by a Seafood Assessment by Sea Choice or a Seafood Report by Monterey Bay Aquarium; both groups use the same assessment criteria. Each assessment synthesizes and analyzes the most current ecological, fisheries and ecosystem science on a species, then evaluates this information against the program’s conservation ethic/sustainability criteria to arrive at a recommendation of “Best Choices”, “Concerns” or “Avoid”. The detailed evaluation methodology is available on our website at www.seachoice.org. In producing Seafood Assessments, Sea Choice 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 scientific reviews of ecological sustainability. Information used to evaluate fisheries and aquaculture practices for assessments regularly comes from ecologists, fisheries and aquaculture scientists, members of industry and conservation organizations. Capture fisheries and aquaculture practices are highly dynamic; as the scientific information on each species changes, Sea Choice’s sustainability recommendations and the underlying Seafood Assessments 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 Assessments in any way they find useful, with acknowledgement. For more information about Sea Choice and Seafood Assessments, please contact the Sea Choice program via e-mail and telephone information available at www.seachoice.org

Sea Choice and Seafood Assessments are made possible through a grant from the David and Lucile Packard Foundation.

1 Rainbow Trout January 2008

Executive Summary

Rainbow trout ( Oncorhynchus mykiss ) are hardy fish that can adapt to a variety of environments, making them ideal fish for aquaculture. They are grown in both land-based and floating cage systems. Land-based production methods include re-circulating systems and freshwater flow- through systems, which consist of concrete raceways or earthen ponds with a continuous flow of freshwater moving through them. The main aquaculture methods used in Canada are floating cages and flow-through systems; re-circulating systems in the Prairie Provinces provide small quantities of fish primarily for local markets. Ontario, where 80% of production comes from floating cages, produces the majority of Canadian farmed trout.

Rainbow trout are carnivorous fish, raising concerns about the appropriation of marine resources for their feed. In the wild, adult trout feed on freshwater shrimp, crustaceans, insects, and fish eggs, while in aquaculture operations they are fed artificial feeds containing fishmeal and fish oil. These are derived from reduction fisheries that target small pelagic fish such as anchovy, herring, and menhaden specifically for their conversion to fishmeal and fish oil. Despite concerns that rainbow trout aquaculture still relies on wild capture fisheries for feed, rainbow trout actually require less than 1 unit (e.g. kg) of fish from the reduction fishery to produce 1 unit (e.g. kg) of trout. Therefore the use of marine resources for rainbow trout aquaculture is low.

In North America, rainbow trout are native to the Pacific coast but have been introduced throughout the continent for sport fishing and aquaculture. They have established feral populations in most Canadian provinces, including in the Great Lakes. Escapes from aquaculture operations are quantitatively small in comparison to the size of these feral populations, and their impact on the aquatic environment and wild stocks is minimal. There have been no recorded escapes from flow-through systems. Cage farms are more susceptible to escapes because of their design, and large escapes have occurred during storm events.

In open cage culture, there is a free exchange of water with the surrounding environment, allowing excess nutrients, dissolved substances, and pathogens to diffuse freely. Solid materials sink to the lake bottom. As the effluent from cages is not treated, this results in changes in the benthic community directly below the farm. Lake-wide effects are also likely on theoretical grounds, but none have been established empirically to date. In addition, aquaculture can cause diseases to be transferred to wild fish, but to date the evidence has been for the reverse – wild fish in the vicinity of cages transmitting diseases and/or parasites to cultured fish.

Flow-through systems are able to treat water before it is discharged into the natural environment. Usually settling ponds are used; these are areas at the ends of raceways or ponds from which fish are absent, allowing suspended particles to settle out of the water. Nevertheless, some suspended solids may still be present in the effluent, as well as any dissolved substances and pathogens. These have been found to alter the biotic community structure downstream of the point of discharge. An increased prevalence of viruses has also been documented, although the risk of retransmission to wild fish is very small.

Rainbow trout aquaculture in Canada is regulated and managed jointly by several federal and provincial agencies. The federal Department of Fisheries and Oceans (DFO) plays the lead role in

2 Rainbow Trout January 2008

developing aquaculture, with implementation of its policies and guidelines carried out by various provincial agencies. This results in a complex management and regulatory framework. As rainbow trout aquaculture continues to grow, better coordination between the many federal and provincial agencies will be necessary. In addition, two critical areas for improving management are the development and implementation of “better management practices” and policies that guide expansion while protecting the natural environment. This will ensure that aquaculture development is sustainable, as per the official DFO vision for Canada.

3 Rainbow Trout January 2008

Table of Sustainability Ranks

Freshwater Flow-Through Systems: Conservation Concern Sustainability Criteria Low Moderate High Critical Use of Marine Resources √ Risk of Escaped Fish √ Risk of Disease and Parasite Transfer √ Risk of Pollution and Habitat Effects √ Management Effectiveness √

Floating Freshwater Cages: Conservation Concern Sustainability Criteria Low Moderate High Critical Use of Marine Resources √ Risk of Escaped Fish √ Risk of Disease and Parasite Transfer √ Risk of Pollution and Habitat Effects √ Management Effectiveness √

Overall Seafood Recommendation:

Freshwater Flow-Through Systems:

Best Choice
Good Alternative
Avoid

Floating Freshwater Cages:

Best Choice
Good Alternative
Avoid

4 Rainbow Trout January 2008

About the Overall Seafood Recommendation: • A seafood product is ranked Avoid if two or more criteria are of High Conservation Concern (red) OR if one or more criteria are of Critical Conservation Concern (black) in the table above. • A seafood product is ranked Good Alternative if the five criteria “average” to yellow (Moderate Conservation Concern) OR if the “Status of Stocks” and “Management Effectiveness” criteria are both of Moderate Conservation Concern. • A seafood product is ranked Best Choice if three or more criteria are of Low Conservation Concern (green) and the remaining criteria are not of High or Critical Conservation Concern.

Introduction

Biology

Rainbow trout ( Oncorhynchus mykiss ) belong to the family Salmonidae and subfamily Salmoninae (Wooding 1994). This species was formerly classified as Salmo gairdneri , but was subsequently found to be more similar to Pacific salmon than to trout, resulting in its reclassification as O. mykiss (Smith and Stearley 1989).

Rainbow trout are hardy fish that have adapted to a variety of environments. They inhabit cold freshwater rivers, streams, and lakes. Spawning and growth are limited to a temperature range of 9-14ºC, but rainbow trout can tolerate temperatures from 0-27ºC (Cowx 2006). Spawning occurs in early spring (April to June), with eggs hatching four to seven weeks later (Scott and Crossman 1973, Wheeler 1985).

Different strains of O. mykiss display different life histories. Most rainbow trout permanently inhabit freshwater environments; some remain within localized areas throughout their life cycles, traveling short distances from natal streams to adjacent larger water bodies. Migratory rainbow trout in the Great Lakes, however, may travel long distances: a rainbow trout tagged in Great Lakes rivers in Michigan was caught eight months later in Lake Ontario, having travelled 375 km (Scott and Crossman 1973). One strain of O. mykiss , known as steelhead, has developed an anadromous life history in which juveniles migrate to the ocean and spend their adult life in marine waters, returning to freshwater streams to spawn (e.g. Scott and Crossman 1973, Wooding 1994, Cowx 2006).

Rainbow trout are native to the Pacific coast and drainages of North America and Asia and to the north Pacific Ocean. In North America, rainbow trout historically occurred west of the Rocky Mountains from Mexico to Alaska (DFO 2003, Cowx 2006). However, they have been introduced throughout North America and the world, to all continents except Antarctica, for sport fishing and aquaculture (Cowx 2006). Their current distribution in Canada, apart from British Columbia, covers the southern parts of Newfoundland, Nova Scotia, Quebec, and Ontario and extends north into central Manitoba, northern Saskatchewan and Alberta, and the Yukon (DFO 2003). Various rainbow trout stocks have been introduced throughout Canada since the late

5 Rainbow Trout January 2008

1800s; the migratory rainbow trout in the Great Lakes originate from the anadromous strain introduced there in 1895 (DFO 2003, Nova Scotia Department of Agriculture and Fisheries 2005).

Production

Rainbow trout aquaculture has been practised in Canada since 1874, but production greatly increased in the 1950s with the introduction of pelleted feeds, and has grown exponentially since that time (Cowx 2006). Rainbow trout are raised in freshwater, brackish water, and marine environments; this report, however, is focused only on freshwater production. In 2005, the global industry produced 291,000 tonnes of fish for a market value of US$911.7 million (FAO 2007). Production is dominated by eight countries: France, Italy, Spain, Denmark, Germany, Iran, the USA and the UK (Cowx 2006).

Canadian rainbow trout production is small in a global context, accounting for approximately 1- 2% of worldwide production by quantity. Nevertheless, it is the largest freshwater aquaculture industry in Canada (DFO 2005). In 2003, Canadian production totalled 5290 tonnes with a value of C$21.6 million (DFO 2005). Rainbow trout are raised commercially in freshwater systems across Canada, in BC, Alberta, Saskatchewan, Manitoba, Ontario, Quebec, New Brunswick, and Prince Edward Island (Lanteigne 2002, Statistics Canada 2006). The largest producer is Ontario, which produced 4075 tonnes of trout in 2005 for a value of $15.5 million (Lanteigne 2002, Moccia and Bevan 2007). The majority is raised in freshwater cage operations in the Great Lakes, of which there were seven totalling 24 hectares in 2002 (Lanteigne 2002). Today there are ten such farms in the Great Lakes (S. Naylor, pers. comm., 16 Oct 2007), as well as one large cage culture operation in Lake Diefenbaker, Saskatchewan. This farm markets its fish as “steelhead” although they are raised exclusively in a freshwater environment. In 2002, their production was approximately 900 tonnes for a value of $4.6 million (Statistics Canada 2006). The remaining production comes from small land-based operations.

Rainbow trout are cultured in land-based and floating cage systems. Land-based production methods include both intensive aquaculture, such as freshwater flow-through and re-circulating systems, and extensive aquaculture. Intensive systems stock fish at high densities in specially- designed facilities and require human intervention, through practices such as feeding, disease treatment, and grading of stock. Extensive operations, on the contrary, stock fish at lower densities in man-made or natural ponds and lakes and leave them undisturbed to grow to adult size. The main aquaculture method used in Canada for commercial purposes is floating cage culture. Land-based systems include flow-through, re-circulating and extensive systems. Re- circulating facilities are used in the Prairie Provinces and provide small quantities of fish primarily for local markets, whereas extensive aquaculture operations often raise fish for private use or as U-fish operations.

The production cycle for rainbow trout begins in freshwater, land-based hatcheries. Eggs are produced from specially-designated brood stock and incubated in hatching troughs or vertical flow incubators (Cowx 2006). Once fry hatch and begin actively searching for food, they are transferred to circular tanks, where they are reared until they reach the fingerling stage (Cowx 2006). At this stage rainbow trout are moved to outdoor, grow-out facilities (Cowx 2006)

6 Rainbow Trout January 2008

Floating cages in freshwater lakes are the major grow-out system used in Canada. They allow free exchange of water with the lake environment, thus allowing rainbow trout to be grown in their natural habitat. Cages are typically 6 m by 6 m squares with a depth of 4-5 m, and can hold up to 100,000 fish (Boyd et al. 2005, Cowx 2006). There is no opportunity for wastewater treatment in cage culture, as all wastes diffuse freely into surrounding waters.

Freshwater flow-through systems consist of concrete raceways or earthen ponds that have a continuous flow of freshwater moving through the facility (Cowx 2006, NOAA 12 Dec 2006). Water is often diverted from adjacent rivers, but may also come from wells or springs (Cowx 2006, O’Neill 2006). Raceways and ponds are typically 12-30 m long, 2-3 m wide, and 1-1.2 m deep (Boyd et al. 2005, Cowx 2006, O’Neill 2006). Several raceways or ponds can be connected in either a linear or parallel setup, as shown in Figure 1. Flow-through systems typically use settling ponds or settling areas at the ends of raceways to treat wastewater before it is discharged (Boyd et al. 2005, Cowx 2006, O’Neill 2006). These are areas from which fish are absent, allowing suspended particles to settle out of the water; the solid wastes may be removed using drains or suction devices (Cowx 2006, O’Neill 2006).

Figure 1. Two typical layouts of freshwater flow-through systems for rainbow trout aquaculture. Water is diverted from an adjacent river and flows through raceways or ponds in either a linear or parallel setup. (Cowx 2006)

During the grow-out period, rainbow trout are graded several times in order to keep fish of similar size together and to maintain optimal stocking densities (Boyd et al. 2005, Cowx 2006). This ensures fast growth and improves feed efficiency (Cowx 2006). Grading is usually done four times (at 2-5 g, 10-20 g, 50-60 g, and >100 g) in a production cycle of 9-12 months. In floating cages, sweep nets are used to crowd fish together so they can be easily removed and sorted, while in flow-through systems a bar grader is used for the same purpose (Cowx 2006, O’Neill 2006). Alternatively, the water level may be lowered so that fish can be netted out (Cowx 2006). With either production method, rainbow trout typically attain market size of 30-40 cm within nine months; they may, however, be grown to larger sizes depending on market demand (Cowx 2006).

Scope of the analysis and the ensuing recommendation:

The recommendation from this analysis is limited to rainbow trout raised in freshwater flow- through systems or floating cages in Canada. Because of the significant differences between these two production methods, they are analysed separately for all criteria except Criterion 1: Use of

7 Rainbow Trout January 2008

Marine Resources. This report is based on the current levels and methods of production. A rapid expansion in the industry could lead to impacts currently not observed to be a problem.

Availability of Science

There is a large volume of literature available regarding rainbow trout biology and some aspects of aquaculture. Many studies have investigated feed characteristics in relation to cost, fish growth, and environmental impacts. There is a considerable body of research available pertaining to land-based flow-through systems. The effluent characteristics of these systems are well- studied, but less research has explored the potential environmental impacts. Freshwater floating cage culture, in contrast, has not been studied much, particularly in Canada where most attention has gone to the farming of Atlantic salmon in marine net-pens. Little science is available regarding the pollution and habitat effects of cage culture, as well as its effects on wild fish populations through escapes and/or disease transmission. However, the Department of Fisheries and Oceans Canada (DFO) is currently undertaking several studies to investigate the environmental effects of freshwater cage culture.

Market Availability

Common and market names: Rainbow trout (also sold as “steelhead” trout).

Seasonal availability: Available year-round.

Product forms: Fresh and frozen whole fish and fillets, smoked products, canned products, value-added products.

Import and export sources and statistics: The majority of Canadian farmed rainbow trout is produced for local and domestic markets. Rainbow trout is not among Canada’s top seafood imports or exports (Statistics Canada 2006).

Analysis of Seafood Watch® Sustainability Criteria for Wild-caught Species

Criterion 1: Use of Marine Resources

Rainbow trout are carnivorous fish. In the wild, fry feed on plankton and shift to a diet consisting of freshwater shrimp, crustaceans, insects, other invertebrates, and fish eggs as they mature (Scott and Crossman 1973, Wheeler 1985, Cowx 2006). Some populations further shift to a piscivorous diet (Scott and Crossman 1973). In aquaculture, however, rainbow trout are fed artificial feeds containing fishmeal and fish oil from the fry stage, when they first start feeding (Boyd et al. 2005, Cowx 2006).

Fishmeal and fish oil used in rainbow trout feeds are derived from reduction fisheries. These are commercial fisheries that target small pelagic fish such as anchovy, herring, menhaden, and mackerel specifically for their conversion to fishmeal and fish oil (i.e. for feed production for aquaculture and other industries) rather than for human consumption (Naylor et al. 2000, O’Neill 2006). Replacement of fishmeal and oil by alternative protein sources such as soy, wheat, maize,

8 Rainbow Trout January 2008

rapeseed, or linseed has resulted in a reduction to less than 50% fishmeal in trout feed (Cowx 2006, Moffitt 2003, Papatryphon et al. 2004). There is continuing research to further reduce the proportions of both fishmeal and fish oil (Adelizi et al. 1998, Cheng and Hardy 2002, Papatryphon et al. 2004).

Reduction in the proportion of fishmeal and oil in feed is both ecologically and economically beneficial (Folke et al. 1998, Naylor et al. 2000). Feed represents the largest single production cost for aquaculture (Naylor et al. 2000). Prices of fishmeal and oil are increasing; this is an economic concern for aquaculture operations. Therefore, decreasing the percentage of fishmeal is a priority, as it will result in more stable prices and better product consistency. Much research has been devoted to alternate sources of protein (Cowx 2006, Moffitt 2003, Naylor et al. 2000, Papatryphon et al. 2004), yet the inclusion of fishmeal in trout feed is still an order of magnitude higher than in poultry and swine feeds (Hardy 2001c in Moffitt 2003, Naylor et al. 2000). Because of this, the aquaculture industry uses a large percentage of annual global fishmeal production (32% in 2000) even though the conversion from fish feed to animal biomass is two to three times more efficient in fish than in poultry and swine (Moffitt 2003).

Yield Rate

Yield rate is the amount of wild fish caught in reduction fisheries that is needed to produce fishmeal and fish oil. Many factors affect and cause variations in yield rate, including fish species, season, condition of fish at capture, fish freshness when processed, and efficiency of the reduction plant (Tyedmers 2000). Fishmeal used in rainbow trout feed includes the Peruvian anchovy ( Engraulis ringens ) (Adelizi et al. 1998); this is the largest global source of fishmeal (Tuominen 2003). Tyedmers (2000) suggests a representative annual average yield rate of 22% for South American fishmeal, which includes the Peruvian anchovy, the South American sardine or pilchard ( Sardinops sagax sagax ), and several other species. This means that 4.5 units of wild fish are required to produce one unit of fishmeal. Fish oil used in rainbow trout feed is derived from Gulf of Mexico menhaden (Adelizi et al. 1998), for which Tyedmers (2000) suggests an average year-round yield rate of 12%. This corresponds to 8.3 units of wild fish needed to produce one unit of fish oil.

Inclusion Rate

The inclusion rate of fishmeal and fish oil in rainbow trout feed varies significantly as the fish mature. Typically, start-up feeds used at the fry stage contain 50% protein and 15-20% fat, while grower feeds contain lesser amounts of both (Hinshaw 1999). The grower diets represent a much larger percentage of the feed consumed over a production cycle, as they are used over a longer time period and with the purpose of putting on biomass (Huntington 2004). Therefore, they are more significant for evaluating the use of marine resources in rainbow trout aquaculture.

A diet formulation provided by a feed supplier to the Canadian rainbow trout aquaculture industry had inclusion rates of 15% and 7-8% for fishmeal and fish oil, respectively. It is difficult to obtain recent published references to commercial diets. In their evaluation of three commercial trout feeds, for example, Okumu and Mazlum (2002) were unable to obtain exact formulations for commercial reasons. In comparison to those provided above, however, those diets which are published have significantly higher inclusion rates for either one or both of fishmeal and fish oil,

9 Rainbow Trout January 2008

For example, Cheng and Hardy (2002) used a control diet that contained 25% fishmeal and 19.5% fish oil, while Adelizi et al. (1998) referenced a “standard commercial trout diet” with 30% fishmeal and 8% fish oil. Huntington (2004) gave a 45% fishmeal inclusion rate. The discrepancy could reflect the success of ongoing research to reduce the amount of fishmeal and oil in feeds. In this report, the Canadian feed supplier’s formulation, with a fishmeal inclusion rate of 15% and fish oil inclusion rate of 7.5%, is used because it is specific to the aquaculture industry in Canada.

Feed Conversion Ratio (FCR)

Rainbow trout are able to efficiently convert the energy in their feed to fish biomass. Feed conversion ratios (FCR), the ratio of feed inputs (dry weight) to farmed fish outputs (wet weight), generally range from 0.9-1.3 (Adelizi et al. 1998, Cheng and Hardy 2002, Huntington 2004, Okumu and Mazlum 2002). The average of this range, an FCR of 1.1:1, is used in this report.

Factor 1: Estimated wild fish used to produce farmed fish (ton/ton), Wild Input to Farmed Output ratio

The Wild Input to Farmed Output ratio (WI:FO) is calculated as the product of yield rate, inclusion rate, and FCR. The calculation is performed separately for both fishmeal and fish oil, and the larger of the two values is used. This avoids double-counting, as fish caught in reduction fisheries are used to produce both fishmeal and fish oil.

Fishmeal: kg 5.4 kg wild fish 15.0 kg fish meal .11 kg feed × × = 74.0 kg wild fish per kg rainbow trout kg 1 kg fish meal 1 kg feed 1 kg rainbow trout

Fish oil: kg .38 kg wild fish .0 075 kg fish oil .11 kg feed × × = 68.0 kg wild fish per kg rainbow trout kg 1 kg fish oil 1 kg feed 1 kg rainbow trout

The WI:FO ratio for farmed rainbow trout is the larger of these two values, 0.74. This means that 0.74 kg of wild fish is needed to produce one kg of farmed rainbow trout. This ranks as a low use of marine resources; thus, this factor receives a green ranking.

Secondary Factor 1: Stock status of the reduction fishery used for feed for the farmed species

The South American fishmeal industry targets several pelagic species, most notably the Peruvian anchovy. These fish stocks are either fully exploited or over-fished, and all are vulnerable to climatic fluctuations such as El Niño Southern Oscillation (ENSO) events (Naylor et al. 2000, Tuominen 2003, Huntington 2004). Fisheries for the Chilean jack mackerel ( Trachurus murphyi ) and the South American pilchard are generally considered to be over-fished (Tuominen 2003, Huntington 2004). The Peruvian anchovy fishery has experienced large fluctuations as a result of over-fishing and El Niño, with annual catches from 1960 to 1999 ranging between 23 thousand

10 Rainbow Trout January 2008

metric tons and 12.3 million metric tons (Pontecorvo 2001). Because of the vulnerability to climatic variations and uncertainty in subsequent recovery, it is difficult to determine whether this fishery is operating at or below maximum sustainable yield.

The fishery for Gulf of Mexico menhaden, used to produce fish oil, is generally considered to be fully exploited but stable. Since 1988, average annual catch has varied between 421,400 t (1992) and 761,600 t (1994) without any trends (Vaughan et al. 2007); stock abundance is influenced by Mississippi River discharge (Vaughan et al. 2000, Hanson et al. 2006). Modeling studies of the Gulf menhaden stock show that fishing mortality and stock status are within biological reference points, although current trends of decreasing population fecundity and increasing fishing mortality must be carefully monitored (Vaughan et al. 2000, 2007).

This factor receives a yellow ranking. Some reduction fisheries for South American fishmeal are over-exploited, while Gulf of Mexico menhaden populations are stable. Furthermore, the stock status of Peruvian anchovy cannot accurately be determined. Secondary Factor 2: Source of stock for the farmed species

Wild fish are not used as brood stock in rainbow trout aquaculture. All brood stock is artificially cultured; facilities either maintain their own brood stock or purchase eggs from closed life cycle hatcheries. This factor is given a green ranking.

Synthesis

For this criterion the green ranking is based on the low WI:FO ratio. However, there is a trend towards high energy diets which contain significantly higher amounts of fish oil. Given the lower yield rate of fish oil in comparison to fishmeal, this could substantially increase the WI:FO ratio and affect the ranking of this criterion in the future.

Criterion 1: Use of Marine Resources

Primary Factor to Evaluate Ranking Wild Input to Farmed Output ratio
Secondary Factors to Evaluate Stock status of reduction fishery
Source of stock

Overall Use of Marine Resources Rank

Criterion 2: Risk of Escaped Fish to Wild Stocks

Factor 1: Evidence that farmed fish regularly escape to the surrounding environment

There is no evidence of rainbow trout escaping from freshwater flow-through systems, although escapes are possible. Barriers or screens are used at inflows and outflows to prevent escapes. High-security raceways with no anticipated losses require screened pipes for both the inflow and outflow, as well as flow-through gravel boxes at the receiving end of outflow pipes (OAA and NBTFA 2002). Many facilities use simpler methods, with lower associated costs and medium

11 Rainbow Trout January 2008

security, to minimize escapes, for example screens across inflows directly from streams. Since there is no evidence of escapes in Canada, this factor receives a green ranking for flow-through systems.

It is difficult to ascertain the frequency of escapes from floating cages. A study of rainbow trout farming in the Alicura Reservoir, Patagonia, Argentina, found evidence of continuous escapes (Temporetti et al. 2001). No studies or statistics are available on the number of escapes in Canada. In 2004, a large hundred-year storm severely damaged one cage in the Great Lakes, resulting in the release of thousands of farmed trout into the wild (S. Naylor, pers. comm., 16 Oct 2007). Such events are extremely rare, however, and otherwise escapes from floating cages occur infrequently (S. Naylor, pers. comm., 16 Oct 2007). Cage culture operations regularly inspect nets for damage, for example through inspection dives every 4-6 weeks, in order to prevent escapes (D. Foss, pers. comm., 13 Dec. 2006). This factor receives a yellow ranking for cage culture, since the exact magnitude of escapes is unknown.

Factor 2: Status of escaping farmed fish to the surrounding environment

In Canada, rainbow trout are native only to the Pacific coast and drainages west of the Rocky Mountains. However, they have been introduced throughout the country, including to all areas in which aquaculture is currently practiced, since the late 1800s. Although rainbow trout are not native to most of the areas in which they are cultured in Canada, they are historically widely distributed; thus, this factor ranks yellow for both flow-through and floating cage systems.

Secondary Factor 1: Where escaping fish is non-native – Evidence of the establishment of self- sustaining feral stocks

The effect of escaping fish is minimal, as rainbow trout have successfully established feral populations throughout Canada since they were first introduced east of the Rocky Mountains in the late 1800s. They continue to be stocked into many lakes in Canada on an annual basis for sport fishing, and provincial stocking programs and commercial fish farms often purchase fingerlings from the same hatchery. This factor receives a yellow ranking for both flow-through and floating cage operations. Escaping fish are able to establish feral stocks, but the impacts of these stocks are negligible in relation to the large feral populations already established through intentional stocking programs. If future farms are proposed in areas without established populations, this factor is relevant.

Secondary Factor 2: Where escaping fish is native – Evidence of genetic introgression through successful crossbreeding

In Canada, rainbow trout are native only to the Pacific coast west of the Rocky Mountains. In this area there is a risk of genetic introgression through crossbreeding. Fuller (2007) gives several examples in which stocked rainbow trout, both within and outside their native range, have compromised the genetic integrity of native trout species through hybridization; this includes native rainbow trout populations in one instance. Other authors, however, have shown that interactions between farmed and wild rainbow trout are minimal due to differences in spawning location and timing (Mackey et al. 2001, McLean et al. 2003). Escaped fish have shown homing behaviour to the hatchery in which they were raised, resulting in spatial segregation from wild

12 Rainbow Trout January 2008

fish (Bridger et al. 2001, Mackey et al. 2001). Farm fish may also be selected for early or late spawning. In Washington State, for example, hatchery-raised fish have been selected for early spawning, and studies have shown temporal separation between the return of hatchery and wild fish (Mackey et al. 2001, McLean et al. 2003). Nevertheless, it is impossible to fully separate wild and hatchery-raised trout spawning in the same stream. If wild and farmed trout do crossbreed, the genetic differences between the two populations will decrease the fitness of hybrids and the genetic integrity of wild trout.

Transgenics have been proposed as a method to protect wild fish stocks from the deleterious effects of crossbreeding. The use of a sterile, triploid, female strain of fish is increasing in popularity for both stocking programs and aquaculture operations (Dillon et al. 2000, Bridger et al. 2001, Teuscher et al. 2003, Lightfoot 2004). Triploid eggs are readily available from commercial hatcheries (Dillon et al. 2000, Troutlodge 2006). This prevents crossbreeding if fish were to escape.

This factor receives a yellow ranking for both culture systems. There is a possibility of crossbreeding and genetic introgression, but it is minimized with the increasing use of sterile strains of fish.

Secondary Factor 3: Evidence of spawning disruption of wild fish

No studies of spawning disruption of wild fish were found. This factor is unknown, and thus ranks yellow for both flow-through and cage culture systems.

Secondary Factor 4: Evidence of competition with wild fish for limiting resources or habitats

No evidence of competition with wild fish for food and habitat has been found to date, although some research suggests it is likely. Over generations, farmed rainbow trout have been selected for adaptation to the aquaculture environment, where they are fed feeds containing fishmeal and fish oil from the fry stage in order to maximize growth. This can result in divergence between farmed and wild fish in traits such as risk-taking and aggression, which affect their interactions in the wild (Berejikian et al. 1996, Biro et al. 2004). Farmed trout have been found to display higher levels of aggression (Berejikian et al. 1996) and to engage in higher-risk feeding behaviour (Biro et al. 2004); the latter behaviour would provide a competitive advantage to escaped fish in areas with low predation (Biro et al. 2004).

In their study of rainbow trout farming in the Alicura Reservoir, Patagonia, Argentina, Temporetti et al. (2001) found that escaped fish displaced wild fish populations. Furthermore, triploid rainbow trout, which are increasingly used in aquaculture to decrease the genetic risks of escapes, were shown to have higher survival rates than diploid fish in two Idaho reservoirs (Teuscher et al. 2003). In an ongoing study of the effects of cage aquaculture on wild fish in Canada, however, no effects have been found to date (S. Naylor, pers. comm., 16 Oct 2007). Fish that were tagged and released to simulate escapes remained close to the cages (S. Naylor, pers. comm., 16 Oct 2007); similar behaviour was found in a study of escaping steelhead from marine cages in Newfoundland (Bridger et al. 2001).

13 Rainbow Trout January 2008

Despite the lack of evidence of competitive interactions to date in Canada, many studies have shown that such interactions are theoretically likely and have occurred in other parts of the world in which rainbow trout farming has a longer history. Therefore, this factor ranks yellow for both land-based flow-through systems and cage aquaculture.

Secondary Factor 5: Stock status of affected wild fish

The stock status of affected wild fish varies geographically. In B.C., 50% of native steelhead populations are listed as being of conservation concern or of extreme conservation concern (BC MWLAP 2002). Large declines in the past few decades are a result of anthropogenic influences and climatic changes (NMFS 12 Dec 2006); even with conservation efforts that include hatchery programs and stream rehabilitation, many populations continue to decrease (NMFS 2006). In the Great Lakes, where the largest proportion of rainbow trout aquaculture occurs, 168 exotic species, from invertebrates to fish, have been introduced, changing the ecosystems of the lakes (S. Naylor, pers. comm., 16 Oct 2007). There are now continuing efforts to restore native fish populations such as lake trout ( Salvelinus namaycush ) (Kitchell et al. 2000). Lake trout populations are increasing, and estimates of mortality rates show that they are near target rates (Kitchell et al. 2000). This factor ranks green for both flow-through and floating cage systems as a reflection of the situation in the Great Lakes Basin, where most rainbow trout aquaculture occurs.

Synthesis

All but one secondary factor for this criterion rank yellow, largely on theoretical grounds. Overall, however, the effects of escaped farm fish in Canada are insignificant in relation to the much larger numbers of rainbow trout intentionally stocked each year for sport fishing. Government agencies have historically stocked and encouraged the management of feral stocks of rainbow trout as a resource within the Great Lakes Basin and in other areas of Canada, including within their native range in British Columbia. Extensive feral populations have been established in this manner, with restocking often using the same fingerling source as aquaculture operations. Thus, the impacts of escaped farm fish are minimal.

This factor receives a green ranking for freshwater flow-through systems, as there is no evidence of escapes from these facilities. Floating cage operations receive a yellow ranking for this factor because escapes have been documented, but their effects are comparatively small.

Criterion 2: Risk of Escaped Fish to Wild Stocks

Primary Factors to Evaluate Flow-Through Floating Cage Ranking Ranking Evidence of escape

Status of escaping fish

Secondary Factors to Evaluate Where non-native: Evidence of feral stocks

Where native: Evidence of genetic introgression

Evidence of spawning disruption of wild fish

14 Rainbow Trout January 2008

Evidence of competition with wild fish

Stock status of affected wild fish

Overall Status of Risk of Escaped Fish Rank

Criterion 3: Risk of Disease and Parasite Transfer to Wild Stocks

Diseases and parasites are able to quickly spread within fish farms because of their high stocking densities; this creates a disease reservoir from which wild stocks can be infected. Rainbow trout aquaculture is susceptible to parasitic infections such as Whirling Disease, caused by the protozoan Myxosoma cerebralis , as well as several bacterial and viral diseases such as infectious pancreatic necrosis (Cowx 2006).

Prevention of disease outbreaks within aquaculture facilities is crucial to mitigating the risks of transfer to wild populations. Establishment of large disease reservoirs can be prevented through proper farm management, including good fish husbandry techniques and sanitation practices. Many studies have also been conducted to examine other methods of improving fish health; these have shown, for example, the health benefits of iodine-supplemented feed (Gensic et al. 2004) or of adding a mannan oligosaccharide to diets (Staykov et al. 2007), as well as the effects of stocking density on fish welfare, stress, and disease susceptibility (North et al. 2006).

Factor 1: Risk of amplification and retransmission of disease or parasites to wild stocks

There is some evidence of disease amplification from freshwater flow-through systems. McAllister and Bebak (1997) found an increased prevalence of Infectious Pancreatic Necrosis Virus (IPNV) to a distance of 19.3 km downstream of two fish culture facilities, but only one case (of 106 fish sampled) of probable retransmission of IPNV to a wild fish. Moreover, a second aquaculture site further downstream did not increase the IPNV load in the stream. This factor receives a yellow ranking because there is empirical evidence for the amplification of pathogens in the effluent of flow-through systems, albeit at low levels that do not appear to pose a significant risk of retransmission.

There is no documented evidence of disease amplification or retransmission within the Great Lakes Basin, where the largest proportion of cage culture occurs. The fish stocks used have a high level of disease resistance; for example, they are almost completely immune to Aeromonas salmonicida , the bacterium causing furunculosis. The only disease of concern in floating cages is cold water disease, caused by the bacterium Flavobacterium psychrophilum , but this is not transferred to wild populations (S. Naylor, pers. comm., 16 Oct 2007). This factor receives a green ranking for floating cages.

Factor 2: Risk of species introductions or translocations of novel disease/parasites to wild stocks

There is no evidence of introductions or translocations to date. Inter-basin fish transfers are highly regulated and transfers from outside the basin require lengthy quarantine in certified facilities. This factor ranks green for flow-through and floating cage systems.

15 Rainbow Trout January 2008

Secondary Factor 1: Bio-safety risks inherent in operations

Freshwater flow-through facilities are able to prevent the spread of some pathogens. Settling ponds or settling areas are used to remove solid wastes from effluents. However, micro- organisms, including disease-causing bacteria or viruses, are not removed with this wastewater treatment method. Parasitic infections, and hence the transmission of parasites, can be prevented by removing habitat for intermediate hosts such as worms or snails. This is accomplished with the use of concrete raceways or fiberglass or concrete tanks, but earthen ponds can provide habitat for intermediate hosts. Overall, land-based systems pose a moderate bio-safety risk and rank yellow for this factor.

Floating cages allow free water exchange with the lake environment. This is a high bio-safety risk, resulting in a red ranking for this factor.

Secondary Factor 2: Stock status of potentially affected wild fish

Wild and stocked rainbow trout and other salmonids may potentially be affected by disease transfer from farmed fish. The stock status of native populations varies with species and region, as described for criterion 2. In addition, the status of introduced fish that have established feral populations, such as rainbow trout, is generally good (Kitchell et al. 2000). This factor receives a green ranking.

Synthesis

There is some evidence of pathogen amplification in freshwater flow-through systems. In combination with the moderate bio-safety risks of current facilities, in which only settling ponds are used to treat effluent, this results in a yellow ranking for this criterion.

Cage aquaculture has a high inherent bio-safety risk, as there is no method of treating effluent. Although there is no evidence of disease or parasite transfer to wild fish stocks to date, this criterion receives a yellow ranking.

Criterion 3: Risk of Disease and Parasite Transfer to Wild Stocks

Primary Factors to Evaluate Flow-Through Floating Cage Ranking Ranking Risk of amplification and retransmission

Risk of species introductions or translocations of novel

disease/parasites Secondary Factors Bio-safety risks inherent in operations

Stock status of potentially affected wild fish

Overall Risk of Disease and Parasite Transfer Rank

16 Rainbow Trout January 2008

Criterion 4: Risk of Pollution and Habitat Effects

Effluent Effects

Factor 1: Effluent water treatment

Freshwater flow-through systems mainly use settling ponds to treat effluent. This removes solid wastes, in which a large proportion of excess nutrients are bound in faeces and uneaten feed, but does not remove dissolved nutrients or other substances. Furthermore, if wastes are not regularly removed from the bottom of settling ponds or settling areas, nutrients are released and leached back into the water as the solids decompose. This factor ranks yellow.

Floating cage systems do not employ any form of effluent treatment. This factor ranks red.

Factor 2: Evidence of substantial local (within 2x the diameter of the site) effluent effects (including altered benthic communities, presence of signature species, modified redox potential, etc.)

Numerous studies have shown increased solid and nutrient loads in the water discharged by flow- through facilities (Axler et al. 1997, Moffitt 2003, Brinker et al. 2005, Maillard et al. 2005). Settling ponds remove most but not all suspended solids from the effluent, while other wastes, such as dissolved excess phosphorus and nitrogen, are not removed. Instead, they are transmitted to the natural environment. In a study of the effluent impacts of five Virginia aquaculture facilities, Helfrich (1998) found that this resulted in localized benthic effects, with increased substrate embeddedness, as well as changes in the biotic community structure immediately downstream of the point of discharge. Sensitive taxa such as mayflies and stoneflies decreased in abundance, while pollution-tolerant non-insect taxa such as isopods and gastropods increased (Helfrich 1998). Furthermore, macroinvertebrate richness decreased (Helfrich 1998). As local effluent effects from flow-through farms have been demonstrated empirically, this factor ranks red.

Floating cage production results in significant local effluent effects through sediment deposition. Solid wastes such as faeces and uneaten feed sink to the lake bottom, substantially altering the benthic community. In a study of the impacts of freshwater cage culture in Canada, Kullman et al. (2007) found that sediments below cages had higher concentrations of carbon, nitrogen and phosphorus, as well as copper and zinc. They also demonstrated biological effects of the altered environment; a bioassay using fingernail clams ( Sphaerium simile ) resulted in 100% mortality in sediments directly below the cages, while 100% survival was recorded for sediments 1 m and further from the cages (Kullman et al. 2007). Because of the experimental evidence of negative local effluent effects, this factor receives a red ranking for floating cages.

Factor 3: Evidence of regional effluent effects (including harmful algal blooms, altered nutrient budgets, etc.)

Phosphorus is the limiting nutrient in freshwater environments, and thus it is the main nutrient of concern for eutrophication. Excess phosphorus and nitrogen may be present in aquaculture effluent in solid forms such as faeces and uneaten feed, as well as in dissolved form. Substantial

17 Rainbow Trout January 2008

research has been performed both to quantify phosphorus levels and bioavailability in effluent and to minimize these levels. The effects of different diets and feeding schedules on phosphorus uptake in rainbow trout have been well studied, resulting in feeding regimes that have successfully increased its retention (Sugiura et al. 1999, Satoh et al. 2003, Papatryphon et al. 2004, Sevgılı et al. 2006).

No studies to date have shown regional effects as a result of the increased levels of bioavailable phosphorus in the effluent of either freshwater flow-through or floating cage systems. There was no evidence of regional effects in Alicura Reservoir, an oligotrophic lake in Patagonia, Argentina, as a result of fish farms (Temporetti et al. 2001). Furthermore, an ongoing study of environmental impacts of cage culture in the Experimental Lakes Area in Canada has not found any regional effects (DFO 2007); instead, it appears that the increased phosphorus levels have gone directly to secondary producers such as invertebrates and minnows rather than to algae (S. Naylor, pers. comm. 18 Oct 2007). This factor receives a green ranking for both culture systems.

Factor 4: Extent of local or regional effluent effects

There are no set standards for effluent effects, except for the phosphorus controls under international agreement on the International Joint Commission. Further information on these standards and their relation to Canadian effluent levels have not been obtained.

In Ontario, the Ministry of the Environment has developed Guidelines for the Protection and Management of Aquatic Sediment Quality. Effect levels ranging from lowest to severe are expressed as concentrations of various elements in the sediment (µg g -1). Sediments taken from below a cage farm had copper concentrations that were near the severe effect level and zinc concentrations that exceeded it (Kullman et al. 2007). No similar studies have been done for flow-through systems.

This factor is unknown for flow-through facilities, and ranks yellow for floating cages, as only one study to date has confirmed the extent of local effluent effects.

Habitat Effects

Factor 1: Potential to impact habitats: Location

Land-based flow-through systems require a constant supply of clean, well-oxygenated water, and thus tend to be located on river or stream shorelines. These are areas of moderate ecological sensitivity, resulting in a yellow ranking.

Cage aquaculture operations are located in freshwater lakes of varying sizes, which are areas of moderate sensitivity. This factor ranks yellow.

Factor 2: Potential to impact habitats: Extent of operations

The extent of operations for both flow-through and cage culture facilities is currently low. Therefore, this factor ranks green.

18 Rainbow Trout January 2008

Most flow-through facilities in Canada are small-scale producers of rainbow trout, not coming near the level of production from the state of Idaho, USA: over 18,000 tonnes in 2004 (O’Neill 2006). The density of sites/area is small; it is two orders of magnitude lower than in Idaho, where there were over 200 production hatcheries along the Snake River in 1995 (Moffitt 2003).

The density of floating cages is low relative to the carrying capacity of the lakes. Of the ten cage farms that currently exist in the Great Lakes, the nearest ones are 5 km apart (S. Naylor, pers. comm., 16 Oct 2007). Salmonids require high water quality; therefore, if the extent of operations were high in comparison to the system’s threshold, farmed rainbow trout would be among the first fish affected. Moreover, the stocking density of fish in floating cages is lower than it is in land-based operations, as it is limited by the amount of oxygen available for fish, which can be artificially enhanced in flow-through systems (S. Naylor, pers. comm., 16 Oct 2007). If fish were stocked above the flushing rate of the ecosystem, they would not obtain sufficient levels of oxygen.

Synthesis

Freshwater flow-through systems have better effluent water treatment than floating cages. Settling ponds are used to remove solid wastes before the effluent is discharged, but filtration, ozonation, or other methods to remove dissolved particles are not commonly employed. With floating cage production, in comparison, it is impossible to implement any wastewater treatment. As empirical evidence of local effluent effects exists for both types of aquaculture operations, criterion 4 ranks yellow for both.

Criterion 4: Risk of Pollution and Habitat Effects

Primary Factors to Evaluate Flow-Through Floating Cage Ranking Ranking Effluent water treatment

Evidence of local effluent effects

Evidence of regional effluent effects

Extent of local or regional effluent effects unknown
Potential habitat impact: Location

Potential habitat impact: Extent of operations

Overall Risk of Pollution and Habitat Effects Rank

Criterion 5: Effectiveness of the Management Regime

Regulation of aquaculture in Canada is complex, with government agencies and legislation at both the provincial and federal levels involved. The Constitution Act of 1867 divided jurisdiction between the provinces and the federal government; for example, the provinces have jurisdiction over species and land, while the federal government has authority over waterways. Hence, responsibility for aquaculture is split between these different levels of government.

19 Rainbow Trout January 2008

The federal Department of Fisheries and Oceans plays the lead role in developing aquaculture in Canada through a national aquaculture framework. Other agencies involved at the federal level include Health Canada, Agriculture and Agri-Food Canada, and Environment Canada (Moccia & Bevan 2000). The application and further, province-specific development of the guidelines established by these federal bodies are left to provincial governments; in each province, responsibilities and jurisdiction have been divided differently, resulting in different ministries involved in aquaculture in each province .For example, in Ontario the Ministry of Natural Resources, the Ministry of the Environment, and the Ministry of Agriculture, Food and Rural Affairs are all involved, while in BC both the Ministry of Water, Land, and Air Protection and the Ministry of Agriculture and Lands have a role to play.

Appendix 1 lists the legislation, from both federal and provincial/territorial agencies, which applies to aquaculture in Canada.

Factor 1: Demonstrated application of existing federal, state and local laws to current aquaculture operations

Existing laws are applied by both flow-through and cage farms, but the level of controls legally required for these different types of operations differs widely. The controls required for flow- through systems are much more rigorous than those for cage culture. In Ontario, for example, anz land-based farms (hence including flow-through systems) must meet the same regulations for effluent treatment as wastewater treatment facilities, while cage culture operations have no similar restrictions. They must monitor water quality on all four sides at a certain distance from the farm and meet prescribed standards that are much less rigorous (G. Kamaitis, pers. comm., 11 Oct 2007). This inconsistency in the regulations and requirements between the different aquaculture systems results in a green ranking for flow-through facilities and a yellow ranking for cage farms.

Factor 2: Use of licensing to control the location (siting), number, size, and stocking density of farms

Licenses are required for all commercial operations, and licensing is used effectively to control rainbow trout farms. The conditions to obtain a license stipulate, for example, a farm separation buffer, which is the minimum distance that a farm must be separated from neighbouring farms. In Ontario, the licensing process requires companies to develop Standard Operating Procedures that detail how the farm will be run and how environmental influences such as ice movement during the winter will be dealt with (S. Naylor, pers. comm., 16 Oct 2007). Furthermore, “Best Management Practices” are also required. This factor currently ranks green for both flow-through and floating cage aquaculture.

Factor 3: Existence and effectiveness of “better management practices” for aquaculture operations, especially to reduce escaped fish

In Ontario, “Best Management Practices” (BMPs) are required during the licensing process for floating cage farms. In addition, a BMP for rainbow trout aquaculture has been developed by the Canadian Aquaculture Industry Alliance (CAIA), but its adoption is voluntary. Several of the requirements are more stringent for land-based systems than for floating cages; this is especially

20 Rainbow Trout January 2008

true of the requirements for effluent treatment, most of which do not apply to floating cages. For example: “Rearing units should be designed for efficient and rapid removal of solids from the water, incorporating settling basins and sediment traps where practical.” (p. 10, CAIA 2002). In addition, some of the wording relating to key issues such as effluent treatment is vague and open to interpretation. Aquaculturists can do very little and remain in compliance with these criteria. For example: “When economically and technically possible, improvements will be made to effluent treatment.” (p. 15, CAIA 2002).

BMPs for land-based flow-through facilities are voluntary; therefore, this factor ranks yellow. Cage farms are required to have BMPs in Ontario, where the majority of cage culture occurs, but the content of these BMPs is unkown. The BMP developed by CAIA is voluntary and moreover is less stringent than for land-based facilities. Overall, this factor ranks yellow for open cages.

Factor 4: 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.)

The primary method of disease treatment is through prevention and early intervention. Vaccines are becoming more common as a preventative measure in rainbow trout aquaculture.

Raceways and ponds provide an excellent opportunity for intervention, ranging from salt baths and other treatments to managing water quality and the culture environment. One of the primary concerns in land-based facilities, especially those on stream supply, is gill disease. This can largely be prevented by controlling environmental conditions, or it may be treated with salt baths or hydrogen peroxide.

Floating cages provide fewer opportunities to prevent and treat diseases and this topic is not well studied. The main preventative measure is to reduce stress, for example by limiting feeding when environmental conditions are unfavourable. Dead fish must also be removed regularly, and medicated feeds are used if needed. However, the use of medicated feeds in Canada is quite rare.

The measures used to prevent and, if necessary, treat disease outbreaks are largely effective for raceways and ponds and less known for floating cages. This factor receives a green ranking for raceways and a yellow ranking for floating cages.

Factor 5: Existence of regulations for therapeutants, including their release into the environment, such as antibiotics, biocides, and herbicides

Therapeutants are federally regulated in Canada. All medications must be used under a veterinary license; they require a veterinary script, which is issued only if a disease is present and diagnosed. Medications cannot be stockpiled in case of emergency, and preventative or prophylactic treatments are not permitted. Therapeutants are thus tightly regulated, resulting in a green ranking for this factor.

21 Rainbow Trout January 2008

Factor 6: Use and effect of predator controls (e.g. for birds and marine mammals) in farming operations

The primary method of predator control used in both land-based and cage farms is bird netting, which prevents birds from catching fish. This method is benign, and thus this factor ranks green.

Factor 7: 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

DFO’s Aquaculture Policy Framework (DFO 2002) is the official federal document that guides further expansion of the rainbow trout aquaculture industry. In addition, DFO is currently conducting experiments in the Experimental Lakes Area of Ontario to study the environmental impacts of freshwater cage aquaculture so as to be able to better inform policy decisions. However, DFO plays a double role in the development of aquaculture, as both a regulator and an enabler. There do not appear to be any guidelines as to which role DFO should take when these twin objectives conflict. A precautionary approach would see the regulatory role trump the enabling role in cases of uncertainty. Because of the controversy surrounding DFO’s dual roles in aquaculture development, this factor ranks yellow.

Synthesis

Rainbow trout aquaculture in Canada is currently well regulated. As it continues to grow, more attention must be given to the development and implementation of “better management practices” and policies that guide expansion while protecting the natural environment. These areas to ensuring that aquaculture development is sustainable, as per the official DFO vision for Canada (DFO 2002). Overall, the current state of management ranks green for flow-through and yellow for floating cage production.

Criterion 5: Effectiveness of the Management Regime

Primary Factors to Evaluate Flow-Through Floating Cage Ranking Ranking Application of existing laws

Use of licensing

“Better management practices”

Measures to prevent disease and to treat outbreaks

Regulations for therapeutants

Predator controls

Policies and incentives to guide expansion

Overall Effectiveness of the Management Regime Rank

22 Rainbow Trout January 2008

Overall Evaluation and Seafood Recommendation

Table of Sustainability Ranks

Freshwater Flow-Through Systems: Conservation Concern Sustainability Criteria Low Moderate High Critical Use of Marine Resources √ Risk of Escaped Fish √ Risk of Disease and Parasite Transfer √ Risk of Pollution and Habitat Effects √ Management Effectiveness √

Floating Freshwater Cages: Conservation Concern Sustainability Criteria Low Moderate High Critical Use of Marine Resources √ Risk of Escaped Fish √ Risk of Disease and Parasite Transfer √ Risk of Pollution and Habitat Effects √ Management Effectiveness √

Overall Seafood Recommendation:

Freshwater Flow-Through Systems:

Best Choice
Good Alternative
Avoid

Floating Freshwater Cages:

Best Choice
Good Alternative
Avoid

23 Rainbow Trout January 2008

References

Adelizi, P.D., R. Rosati, K. Warner, Y. Wu, T. Muench, M. White, and P. Brown. 1998. Evaluation of fishmeal free diets for rainbow trout, Oncorhynchus mykiss . Aquaculture Nutrition. 4: 255-262.

Axler, R.P., C. Tikkanen, J. Henneck, J. Schuldt and M.E. McDonald. 1997. Characteristics of effluent and sludge from two commercial rainbow trout farms in Minnesota. Progressive Fish-Culturist. 59: 161-172.

BC Ministry of Water, Land, and Air Protection (BC MWLAP). 2002. Environmental Indicator – Fish in British Columbia. Available at http://www.env.gov.bc.ca/soerpt/4fish/steelhead.html Accessed 22 October 2006.

Berejikian, B.A., S.B. Mathews and T.P. Quinn. 1996. Effects of hatchery and wild ancestry and rearing environments on the development of agonistic behavior in steelhead trout (Oncorhynchus mykiss ) fry. Canadian Journal of Fisheries and Aquatic Sciences. 53: 2004-2014.

Biro, P.A., M.V. Abrahams, J.R. Post and E.A. Parkinson. 2004. Predators select against high growth rates and risk-taking behaviour in domestic trout populations. Proceedings of the Royal Society of London, Series B, Biological Sciences. 271: 2233-2237.

Bridger, C.J., R.K. Booth, R.S. McKinley and D.A. Scruton. 2001. Site fidelity and dispersal patterns of domestic triploid steelhead trout ( Oncorhynchus mykiss Walbaum) released to the wild. ICES Journal of Marine Science. 58: 510-516. doi:10.1006/jmsc.2000.1041

Brinker, A., W. Koppe and R. Rösch. 2005. Optimizing trout farm effluent treatment by stabilizing trout feces: A field trial. North American Journal of Aquaculture. 67: 244-258.

Boyd, C., A. McNevin, J. Clay, and H. Johnson. 2005. Certification issues for some common aquaculture species. Reviews in Fisheries Science. 13: 231-279.

Canadian Aquaculture Industry Alliance (CAIA). 2002. Management Practices for Sustainable Aquaculture in Freshwater.

Cheng, Z. and R. Hardy. 2002. Apparent digestibility coefficients and nutritional value of cottonseed meal for rainbow trout ( Oncorhynchus mykiss ). Aquaculture. 212: 361-372.

Cowx, I.G. Updated Mon 09 Oct 2006 09:58:51 CEST. Cultured Aquatic Species Information Programme - Oncorhynchus mykiss . Cultured Aquatic Species Fact Sheets. FAO Inland Water Resources and Aquaculture Service (FIRI). FAO - Rome. http://www.fao.org/figis/servlet/static?dom=culturespecies&xml=Oncorhynchus_mykiss. xml Accessed 28 October 2006.

24 Rainbow Trout January 2008

Department of Fisheries and Oceans Canada (DFO). 2002. DFO’s Aquaculture Policy Framework. http://www.dfo-mpo.gc.ca/aquaculture/ref/APF_e.htm Accessed 13 October 2007.

Department of Fisheries and Oceans Canada (DFO). 2003. National Factsheet – Rainbow Trout. http://www.dfo-mpo.gc.ca/canwaters-eauxcan/infocentre/guidelines-conseils/factsheets- feuillets/national/rainbowtrout_e.asp Accessed 29 November 2006.

Department of Fisheries and Oceans Canada (DFO). 2005. Canadian Aquaculture Industry 2003- 2004 Key Figures. http://www.dfo-mpo.gc.ca/aquaculture/ref/CAIKF0304_e.htm Accessed 29 October 2006.

Department of Fisheries and Oceans Canada (DFO). 2007. Ecosystem experiment to assess environmental impacts of freshwater cage aquaculture. http://www.dfo- mpo.gc.ca/science/aquaculture/acrdp-pcrda/ca/CA-01-09-001_e.htm Accessed 5 October 2007.

Dillon, J.C., D.J. Schill and D.M. Teuscher. 2000. Relative return to creel of triploid and diploid rainbow trout stocked in eighteen Idaho streams. North American Journal of Fisheries Management. 20: 1-9.

Folke, C., N. Kautsky, H. Berg, A. Jansson, and M. Troell. 1998. The ecological footprint concept for sustainable seafood production: A review. Ecological Applications. 8: S63- S71.

Food and Agriculture Organisation of the United Nations (FAO). 2006b. Yearbooks of Fishery Statistics – Summary Tables. Table A6: World aquaculture production of fish, crustaceans, molluscs, etc., by principal species in 2005. ftp://ftp.fao.org/fi/stat/summary/a-6.pdf Accessed 13 October 2007.

Food and Agriculture Organisation of the United Nations (FAO). 2007. Global Aquaculture Production Statistics. Available at http://www.fao.org/figis/servlet/static?dom=root&xml=aquaculture/index.xml Accessed 13 October 2007.

Fuller, P. 2007. Oncorhynchus mykiss . USGS Nonindigenous Aquatic Species Database, Gainesville, FL. http://nas.er.usgs.gov/queries/factsheet.asp?SpeciesID=910 Revision Date: 4/20/2006.

Gensic, M., P.J. Wissing, T.R. Keefe and A. Mustafa. 2004. Effects of iodized feed on stress modulation in steelhead trout, Oncorhynchus mykiss (Walbaum). Aquaculture Research. 35: 1117-1121.

Hanson, P.J., D.S. Vaughan and S. Narayan. 2006. Forecasting annual harvests of Atlantic and Gulf menhaden. North American Journal of Fisheries Management. 26: 753-764.

25 Rainbow Trout January 2008

Helfrich, L.A. 1998. Impacts of trout culture effluent on water quality and biotic communities in Virginia headwater streams. The Progressive Fish-Culturist. 60: 247-262. DOI: 10.1577/1548-8640(1998)060<0247:IOTCEO>2.0.CO;2

Hinshaw, J. 1999. Trout Production: Feeds and Feeding Methods. Southern Regional Aquaculture Center Publication SRAC-223.

Huntington, T.C. 2004. Feeding the fish: Sustainable fish feed and Scottish aquaculture. Report to the Joint Marine Programme (Scottish Wildlife Trust and WWF Scotland) and RSPB Scotland.

Kitchell, J.F., S.P. Cox, C.J. Harvey, T.B. Johnson, D.M. Mason, K.K. Schoen, K. Aydin, C. Bronte, M. Ebener, M. Hansen, M. Hoff, S. Schram, D. Schreiner and C.J. Walters. 2000. Sustainability of the Lake Superior fish community: Interactions in a food web context. Ecosystems. 3: 545-560.

Kullman, M.A., C.L. Podemski, K.A. Kidd. 2007. A sediment bioassay to assess the effects of aquaculture waste on growth, reproduction, and survival of Sphaerium simile (Say) (Bivalvia: Sphaeriidae). Aquaculture. 266: 144-152.

Lanteigne, S. 2002. Current status and potential of the Canadian aquaculture industry. Office of the Commissioner for Aquaculture Development (OCAD) Study No. 1. http://govdocs.aquake.org/cgi/content/abstract/2004/410/4100160 Accessed 15 October 2007.

Lightfoot, G. 2004. Triploid trout in native trout waters: Phase 1--literature review and recommendations for Phase 2. Trout News. 38: 25-26.

Mackey, G., J.E. Mclean ad T.P. Quinn. 2001. Comparisons of run timing, spatial distribution, and length of wild and newly established hatchery populations of steelhead in Forks Creek, Washington. North American Journal of Fisheries Management. 21: 717-724.

Maillard, V.M., G.D. Boardman, J.E. Nyland and D.D. Kuhn. 2005. Water quality and sludge characterization at raceway-system trout farms. Aquacultural Engineering. 33: 271-284.

McAllister, P.E. and J. Bebak. 1997. Infectious pancreatic necrosis virus in the environment: Relationship to effluent from aquaculture facilities. Journal of Fish Diseases. 20: 201-207.

McLean, J.E., P. Bentzen, and T..P. Quinn. 2003. Differential reproductive success of sympatric, naturally spawning hatchery and wild steelhead trout (Oncorhynchus mykiss) through the adult stage. Canadian Journal of Fisheries and Aquatic Sciences. 60: 433-440.

Moccia, R.D. and D.J. Bevan. 2000. Aquaculture Legislation in Ontario. http://www.aps.uoguelph.ca/~aquacentre/aec/publications Accessed 6 October 2007.

Moccia, R.D. and D.J. Bevan. 2007. Aquastats: Ontario Aquacultural Production in 2005. http://www.aps.uoguelph.ca/~aquacentre/aec/publications Accessed 18 October 2007.

26 Rainbow Trout January 2008

Moffitt, C.M. 2003. The Implications of Aquaculture Production and Development on Sustainable Fisheries. Symposium on Sustainable Fisheries, American Fisheries Society.

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. 405: 1017-1024.

NOAA. Korea-US Aquaculture. Raceway Culture for Freshwater Species. http://www.lib.noaa.gov/korea/korean_aquaculture/raceway.htm Accessed 12 December 2006.

NOAA National Marine Fisheries Service (NMFS). Pacific Salmonids: Major Threats and Impacts. http://www.nmfs.noaa.gov/pr/species/fish/salmon.htm Accessed 12 December 2006.

NOAA National Marine Fisheries Service (NMFS). 2006. Steelhead Trout ( Oncorhynchus mykiss ). http://www.nmfs.noaa.gov/pr/species/fish/steelheadtrout.htm Accessed 12 December 2006.

North, B.P., J.F. Turnbull, T. Ellis, M.J. Porter, H. Migaud, J. Bron and N.R. Bromage. 2006. The impact of stocking density on the welfare of rainbow trout ( Oncorhynchus mykiss ). Aquaculture. 255: 466-479.

Nova Scotia Department of Agriculture and Fisheries. 2005. Factsheet: Rainbow Trout (Oncorhynchus mykiss ). http://www.gov.ns.ca/nsaf/sportfishing/species/rain.shtml Accessed 29 November 2006.

Okumu , Đ and M.D. Mazlum. 2002. Evaluation of commercial trout feeds: Feed consumption, growth, feed conversion, carcass composition and bio-economic analysis. Turkish Journal of Fisheries and Aquatic Sciences. 2: 101-107.

O’Neill, B. 2006. US Farmed Rainbow Trout Seafood Watch Report. Available at http://www.mbayaq.org/cr/SeafoodWatch/web/sfw_factsheet.aspx?fid=64 Accessed 21 September 2006.

Ontario Aquaculture Association (OAA) and New Brunswick Trout Farmers Association. (NBTFA) (eds.) 2002. Guide for Fish Containment in Land-Based Aquaculture Facilities.

Papatryphon, E., J. Petit, S.J. Kaushik, and H.M.G. van der Werf. 2004. Environmental impact assessment of salmonid feeds using Life Cycle Assessment (LCA). Ambio. 33: 316-323.

Pontecorvo, G. 2001. Supply side uncertainty and the management of commercial fisheries: Peruvian Anchovetta, an illustration. Marine Policy. 25: 169-172.

27 Rainbow Trout January 2008

Satoh, S., A. Hernández, T. Tokoro, Y. Morishita, V. Kiron, and T. Watanabe. 2003. Comparison of phosphorus retention efficiency between rainbow trout ( Oncorhynchus mykiss ) fed a commercial diet and a low fishmeal based diet. Aquaculture. 224: 271-282.

Scott, W.B. and E.J. Crossman. 1973. Freshwater Fishes of Canada. Bulletin 184. Ottawa: Fisheries Research Board of Canada.

Sevgılı, H., Y. Emre, M. Kanyilmaz, Đ. Dıler and B. Ho su. 2006. Effects of mixed feeding schedules on growth performance, body composition, and nitrogen- and phosphorus balance in rainbow trout, Oncorhynchus mykiss . Acta Ichthyologica et Piscatoria. 36: 49- 55.

Smith, G.R. and R.F. Stearley. 1989. The classification and scientific names of rainbow and cutthroat trouts. Fisheries 14: 4-10.

Statistics Canada. 2006. Aquaculture Statistics 2005. Catalogue No. 23-222-XIE. http://www.statcan.ca/cgi-bin/downpub/freepub.cgi?subject=920#920 Accessed 13 October 2007.

Staykov, Y., P. Spring, S. Denev and J. Sweetman. 2007. Effect of a mannan oligosaccharide on the growth performance and immune status of rainbow trout ( Oncorhynchus mykiss ). Aquaculture International. 15: 153-161. DOI 10.1007/s10499-007-9096-z

Sugiura, S.H., V. Raboy, K.A. Young, F.M. Dong, and R.W. Hardy. 1999. Availability of phosphorus and trace elements in low-phytate varieties of barley and corn for rainbow trout ( Oncorhynchus mykiss ). Aquaculture. 170: 285-296.

Temporetti, P.F., M.F. Alonso, G. Baffico, M.M. Diaz, W. Lopez, F.L. Pedrozo and P.H. Vigliano. 2001. Trophic state, fish community and intensive production of salmonids in Alicura Reservoir (Patagonia, Argentina). Lakes & Reservoirs: Research and Management. 6: 259-267.

Teuscher, D.M., D.J. Schill, D.J. Megargle and J.C. Dillon. 2003. Relative survival and growth of triploid and diploid rainbow trout in two Idaho reservoirs. North American Journal of Fisheries Management. 23: 983-988.

Troutlodge. History. http://www.troutlodge.com/home.html Accessed 15 December 2006.

Tuominen, T.-R. 2003. Food for thought: The use of marine resources in fish feed. WWF- Norway Report 02/03.

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.

Vaughan, D.S., J.W. Smith and M.H. Prager. 2000. Population Characteristics of Gulf Menhaden, Brevoortia patronus . NOAA Technical Report NMFS 149.

28 Rainbow Trout January 2008

Vaughan, D.S., K.W. Shertzer and J.W. Smith. 2007. Gulf menhaden ( Brevoortia patronus ) in the U.S. Gulf of Mexico: Fishery characteristics and biological reference points for management. Fisheries Research. 83: 263-275.

Wheeler, A. 1985. The World Encyclopedia of Fishes. London, England: Macdonald and Co. Publishers Ltd.

Wooding, F.H. 1994. Lake, River, and Sea-Run Fishes of Canada. Madeira Park: Harbour Publishing.

29 Rainbow Trout January 2008

APPENDIX 1: Aquaculture Legislation in Canada From: CAIA 2002

Federal Legislation

Fisheries Act of Canada Conservation, protection and enhancement of fish Fish Health Protection Regulations Control of infectious fish diseases General and Provincial Regulations Management of wild fisheries

Fish Inspection Act and Regulations Inspection of fish safety and quality Canada Food Safety and Inspection Act Product safety/quality for export Freshwater Fish Marketing Act

Navigable Waters Protection Act Location, a pproval, marking of structures

Food and Drugs Act Animal drug use approval Feeds Act of Canada Quality and safety of animal feeds

Health of Animals Act Registration/import of vaccines Pest Control Products Act Registration of pesticides Management of Contaminated Fisheries Regulations

Canadian Environmental Protection Act Environmental protection & conservation Canadian Environmental Assessment Act Pre-assessment of development

Migratory Birds Convention Act Protection of specific birds

Goods and Services Act General sales tax

Provincial & Territorial Legislation

Alberta Alberta Fisheries Act & Regulations Alberta Water Act

British Columbia Fisheries Act (BC) Aquaculture Regulations Fisheries Act Regulations Inspections Act & Inspection Regulation Animal Disease Control Act Farm Practices Act Protection (Right to Farm) Act Farming and Fishing Industries Development Act Wildlife Act Pharmacists, Pharmacy Operation and Drug Handling Act Water Management Act Waste Management Act

30 Rainbow Trout January 2008

Aquaculture Waste Control Regulation Land-based Fin Fish Waste Control Regulation Lands Act

Manitoba Manitoba Fisheries Regulations The Environment Act and Regulations Classes of development, licensing procedures, fees The Water Rights Act and Regulations Fisheries Act Licencing and fee regulations Public Health Act and Regulations Food handling

Newfoundland Aquaculture Act & Aquaculture Regulations Environment Act

New Brunswick Aquaculture Act & Aquaculture Regulations Fish and Wildlife Act

North West Territories North West Territories Fisheries Regulations

Nova Scotia Fisheries and Coastal Resources Act Aquaculture Act Legislation/procedures for leasing & licencing Aquaculture Regulations and Policy Conditions for operation Environment Act Environmental protection Endangered Species Act Protecting & preserving threatened species & habitat Municipal Act Local by-laws and land use Water Act Withdrawal or diversions of water Minerals Act Advisory role in present or future conflicts Forest Act Advisory role in present or future conflicts

Ontario Fish and Wildlife Conservation Act Licensing of fish farms Lakes and Rivers Improvement Act Construction approvals Conservation Authorities Act Flood plain habitat protection Beds of Navigable Waters Act Leasing of lake bed for cages Public Lands Act Access to cage culture sites Aggregate Resources Act Removal from watercourses Fish Inspection Act Product safety & quality Ontario Water Resources Act Surface & groundwater quantity & quality Environmental Protection Act Environmental protection Environmental Assessment Act Design & construction requirements Pesticides Act Pesticide registration & use Planning Act Land use planning/development

31 Rainbow Trout January 2008

Farming and Food Production Protection Economic development, R&D, rural programs Act Municipal Act Local by-laws e.g. land use Drainage Act Surface water drainage/discharge Veterinarians Act Regulation of drug use Occupational Health and Safety Act Worker health & safety Highways Act Wells near highways Corporations Information Act Company registration &/or Incorporation

Prince Edward Island Fish and Game Protection Act/Wildlife Conservation Act Fisheries Act control and licencing of fish buyers and processing facilities Environment Protection Act Fish Inspection Act Prescribes grades, quality and standards of fish Maritime Provinces Fishery Regulations Prohibits live use of bait from other provinces Natural Area Protection Act Usage for designated natural area for protection Pesticides Control Act Controls licencing, storage, use and disposal Revenue Tax Act Lists products tax exempt for aquaculture operations Gasoline Tax Act Purchase of tax exempt, marked gasoline

Quebec Loi sur les pêcheries et l'aquaculture Establishment and operation of fish farms and fee commerciales fishing operations Loi sur la conservation et la mise en valeur Permitted species for fish culture and stocking de la faune Loi sur la qualité de l'environement Design, construction and operation of fish farms Loi sur l'aménagement et l'urbanisme Development and construction permits Loi sur la protection du territoire agricole Use of farm lands Loi sur les terres du domaine de l'Etat Natural resources management Loi sur le régime des eaux Regulation of water control structures Loi sur les produits agricoles, les produits marins Processing and food safety et les aliments Loi concernant les propriétaires et exploitants Fish transportation regulation de véhicules lourds Loi sur les producteurs agricoles Farm registration Loi sur le ministère de l'Agriculture, des Pêcheries et de l'Alimentation Loi sur la santé et la sécurité au travail Worker health and safety Loi sur les compagnies Company registration

Saskatchewan Fisheries Act (Saskatchewan) Gives authority to minister and officers with respect to fish farming; authority of Lieutenant-Governor to make regulations Fishery Regulations (pursuant to Act) Licensing of fish farms, marketing, imports, therapeutants, disease reporting

32 Rainbow Trout January 2008

Environmental Management and Protection Act Shoreline alterations, sewage disposal Wildlife Act Protection of wild species at risk Water Corporation Act Approval for withdrawal of surface or ground water for industrial use Environmental Assessment Act Environmental impact assessment requirements Provincial Lands Act Leases

Yukon Yukon Fisheries Regulations

33