Muddy waters

Muddy waters

Aquaculture has been charged with multiple crimes against the environment. But today fish farms must abide by stringent regulations while many wild fish populations are being decimated. Can we learn to live with this industry?

By Douglas Hunter

It is harvest day at Depot Harbour on the north shore of Parry Island. The mid-March sky over eastern Georgian Bay is bright, but the temperature is below freezing as farmhands gather on a floating dock at Aqua-Cage Fisheries. The water, which mechanical agitators prevent from icing over, is streaked with iridescent flashes. An Archimedes screw inside a plastic tube gently slurps up one-kilo rainbow trout from a seine-net cage, one of an array lining the shore, and deposits them in a waist-high plastic shipping container called a tote that can hold 400 kilograms of fish.

“On a typical harvest day, we’ll fill up to 20 to 24 totes,” says Gord Cole as we watch the trout whirl up the tube. A truck will soon arrive to take them to a processing plant in St. Thomas, Ontario. From there, trout fillets are shipped to retailers and restaurants in Montreal, Toronto, Chicago and points between.

Between 1,000 and 1,100 tonnes of rainbows emerge annually from Aqua-Cage’s pens. It is the largest cage-aquaculture fish farm in Ontario, producing a fifth to a quarter of the province’s rainbow trout, and is the second largest freshwater operation in Canada. Cole, a fit 50-something who does canoe and dragon boat racing in his spare time, founded the company in 1982 after earning a biology degree at the University of Waterloo. He believes he was the first to use Norwegian cage-aquaculture technology in fresh water anywhere in the world.

Many fish farms use feed made from other fish, and the aquaculture industry’s demand for great volumes of commercial feed is putting a strain on some ocean species. This is a serious issue for the industry, not least because it belies the image of farmed fish as a responsible consumer choice that relieves pressure on global fish stocks.

The problem is that cold-water carnivorous salmonid species, such as salmon and the trout raised in Ontario fish farms, require fish meal and fish oil for their growth. (Warm-water herbivore and omnivore species like catfish, tilapia and carp can be raised on feed with minimal animal meal or oil.) Ocean species such as anchovy have been placed under tremendous stress by the global demand of the aquaculture industry for inexpensive fish meal and oil. A study of aquaculture production based on 1997 practices determined that every one kilogram of farmed salmon required 3.16 kilograms of wild fish; trout required 2.46 kilograms.

The industry is trying to find feed alternatives, such as new blends that derive some of their content from blood meal and poultry by-products, as well as from plants. But because of amino acid balances, salmonids cannot tolerate a substantial amount of plant-derived protein. A “high-nutrient dense grower diet” for
salmonids, developed at the Fish Nutrition Research Laboratory at the University of Guelph, shows some promise as a replacement feed. The blend includes 20 percent fish oil, 18 percent fish meal, 13 percent poultry by-product, 38 percent corn gluten meal and 9 percent dried whey.

Still, with feed the single largest expense for fish farms, persuading operators to switch to more expensive, environmentally friendly alternative feed will be difficult.

Unfortunately, that might only happen when wild fish stocks are depleted to the point that feed made from them becomes too pricey.
Douglas Hunter

Spend a morning with Cole down on the fish farm and you will absorb a stream of pride, fish facts and frustration. Cole is intensely interested in the science and best practices of his business. In August 1999, he presented a paper on aquaculture water quality to a roundtable hosted by the Habitat Advisory Board of the Great Lakes Fishery Commission, and the Great Lakes Water Quality Board of the International Joint Commission. He advocated a costly “fallowing” practice of moving cage sites seasonally in order to reduce the accumulation of waste on lake bottoms, and stronger rules aimed at preventing genetic cross-contamination between farmed and wild stocks. Already, he was employing “green” measures at his own operation: he’d switched to low emission four-stroke outboards on his boats, bought feed in bulk to minimize packaging waste and used environmentally friendly hydraulic fluids.

A decade later, however, Cole fears for his industry’s future. He calls the current regulation of fish farming “dysfunctional.” His detractors argue that he has put a farm where it does not belong – in public waters, imperilling human health, water quality and biodiversity. He and his colleagues counter that cage aquaculture is a responsible, homegrown source of fish for our dinner plates and provides jobs in regions of chronic unemployment. Fish farmers contend that their local environmental impact is manageable and can even be beneficial.

Ontario’s cage-aquaculture operators are counting on research to prove the environmental sustainability of their practices in order to ensure their economic survival. But they may not endure long enough to benefit from it unless a regulatory overhaul takes place. The Ontario Ministry of Natural Resources (MNR) oversees the industry under the Fish and Wildlife Conservation Act, issuing five-year operating licences. These are difficult to obtain, requiring applicants to go through an approval process that involves municipal, provincial and federal governments, First Nations reserves and some 22 different laws covering everything from water quality to navigation rights. The licences are not renewed: after five years, operators have to go through the whole approval process again. In January, MNR released a draft of new guidelines designed to create consistent standards and a coherent, if still complex, four-stage application review. Even if adopted, a start-up business would require three years or more to run this regulatory gauntlet successfully.

“It’s kind of an interesting time,” Cole says as he walks along the floating dock between the cages, pointing out trout of different ages growing in Depot Harbour. “The new licensing policies might not be finalized before the next time I have to get a licence. Not a single licence has been renewed on time in Ontario, despite the best efforts of the farmers.” After 27 years, he worries that MNR could demand a different operating regimen and put him out of business.
Aquaculture has many permutations, but essentially it involves cultivating aquatic species as a commercial crop. Fish are raised either in land facilities (tanks) or in openwater “cages,” usually formed by seines. In Canada, cage aquaculture dominates, and it is used mainly to raise salmonids – salmon and trout – in both fresh and salt water.

According to Rich Moccia, professor of acquatic and fisheries science and chair of the master’s in science in aquaculture degree program at the University of Guelph’s Aquaculture Centre, about 150 licensed fish farms operate in Ontario. About half of those are hobby farms – private rural retreats with stocked ponds. The rest are divided among businesses like Aqua-Cage that produce fish for the market, hatcheries that supply fingerlings to those farms and to sport-fish stocking programs, and fishing ponds for recreation and tourism. While some operators cultivate Arctic char, brook trout, bass and tilapia, Moccia estimates that 99 percent of Ontario’s farmed fish is rainbow trout. The aquaculture farms produce around 4,000 to 4,400 tonnes annually, which has a wholesale farmgate value of $16 to $18 million.

The great majority of those rainbows come from just a few cage operations, and all of them except Aqua-Cage are in Lake Huron’s North Channel region. Cold Water Fisheries, the largest single player, has three operations in that area. The industry is a small one that has not grown much. “Only one new cage-aquaculture licence has been issued in the last nine years,” says Moccia.

The reason? Cage aquaculture practices have been subjected to close scrutiny. Environmental Commissioner of Ontario Gord Miller criticized the industry in his 2000/01 report. The Georgian Bay Association (GBA), an umbrella organization of 23 waterfront ratepayer groups on the east side of Georgian Bay and Ontario Nature member group, has been campaigning vigorously for a decade for the total elimination of cage aquaculture, lately arguing that anything less would be a failure by Ontario to meet its obligations to its U.S. partners in improving Great Lakes water quality. Indeed, none of the U.S. Great Lakes states currently permit cage aquaculture.

Issues raised by the ECO report were multifold, but the main rap continues to be cage aquaculture’s impact on water quality. The ECO report stated “cages are not necessary to aquaculture: the fish species now raised in cages can also be raised in other types of facilities, such as man-made ponds, raceways and tanks.” It suggested that fish were mainly being raised in cages to avoid the environmental regulations on effluent discharge that apply to tanks. Bob Duncanson, executive director of the GBA, agrees, claiming that the phosphorus production of untreated waste on fish farms is “the equivalent of [that of] 8,000 market hogs.” In a spring 2009 newsletter, GBA president Mary Lee wrote that the problems with cage aquaculture come down to “one core issue – the fact that, alone in Ontario, this industry is exempt from the provincial requirement for feedlot operations to manage effluents.” The association wants the industry either to develop floating cages with “closed containment” or move to land-based tanks.

The Department of Fisheries and Oceans (DFO) is investigating closed-containment cage systems, but Moccia says the ECO report was wrong about cages being unnecessary, at least where rainbow trout are concerned. “It’s primarily an economic and production capacity issue,” he explains. Without using open-water cages, “you can’t raise the quantity of fish at a price per unit to be competitive, or even economically viable. Wholesale prices being paid to fish farmers haven’t gone up in 15 to 20 years, and in fact have gone down a bit.” The economic argument may not placate critics of aquaculture, but Moccia also argues that “fish farmers are very good stewards of the environments they manage.” Regulations require operators to monitor and report water quality. Farm must also meet stringent standards on phosphorus levels in order to ward off algal blooms and bacterial growth that cause oxygen depletion of the surrounding water.

The water-quality issue highlights a central problem in the debate: not enough is known about the relationship between cage-raised fish and the surrounding freshwater environment. Moccia, who consulted on MNR’s draft guidelines, thinks the proposed water-quality standards are based on the best available scientific foundation. But, he says, “there’s been some arbitrary setting of regulatory points, both on the high and low sides. We don’t have all the science in place to say what is acceptable and not acceptable, and it’s been very challenging to get the government to come forward with a rationale on criteria.”

The lack of hard data provoked a multi-year study, at the Experimental Lakes Area (ELA) of northwestern Ontario, of the impact of cage aquaculture. Run by the DFO, the ELA is known for producing key findings on acid rain and for identifying the role of phosphates in lake eutrophication (lake “aging” through oxygen depletion). After two years of baseline studies on the ecology of pristine Lake 375, researchers set up a working cage-aquaculture farm in 2003 and ran it until 2007. Since then, they have been monitoring the recovery of the site.

The study deliberately stressed the small, 23-hectare lake by stocking a farm on it every spring with 10,000 rainbow trout. Lake 375 is “tiny in comparison to a lake normally used for aquaculture,” says Cheryl Podemski, a research scientist at DFO’s Freshwater Institute in Winnipeg who leads the project. “We’re trying to use it as a model, to get at all the different ecosystem components.” Not all results have been published, but one finding is the impact of phosphorus. “We’re certainly seeing less ecological effect than we might have thought,” says Podemski. “It suggests that phosphorus we’re adding as fish farm waste is [having a different effect]” than other forms, such as phosphorus from fertilizer and septic leaching. Podemski suspects that the fish-farm phosphorus is sinking quickly to the bottom of the lake and resting in sediment and so does not promote algal growth in the upper layers of lake water. What will happen to that phosphorus in the sediment over the long term remains unknown. “Also, some phosphorus is going into fish production, both farm fish and wild,” she says, thus promoting growth of fish rather than algae or bacteria.

Opponents of aquaculture are likely to be skeptical of the findings. For starters, the grant for the Lake 375 study required a commercial research partner, and the Northern Ontario Aquaculture Association (NOAA) stepped up. Operators in 2002 formed the NOAA, headquartered in Little Current, in the wake of the ECO report.

Podemski says the NOAA’s financial contribution was relatively small. More important was the trade group’s cooperation in setting up the fish farm, training researchers and allowing scientists unfettered access to their operations for sediment sampling and other tests. “They all understand that they have no right to review data before publication, but they’ve been willing to provide complete cooperation,” Podemski says. “I’ve found that impressive.”

Nevertheless, the GBA accuses both DFO and Environment Canada of having conflicts of interest with respect to aquaculture oversight. In its submitted comments on the draft MNR guidelines, the GBA asked how the DFO can “justify its stated responsibility: ‘for helping to improve the business climate for aquaculture,’ when such help amounts to a government approved public subsidy for a private for-profit industry, by allowing it free use and abuse of the public waterways and aquatic ecosystem?” And in Ontario, there has long been an inherent regulatory dichotomy within the government, with the Ministry of the Environment being concerned about aquaculture’s impact on water quality, and the Ministry of Agriculture, Food and Rural Affairs being committed to helping the aquaculture industry grow and supporting the associated research at the University of Guelph.
Not all research into cage aquaculture has boosted the industry’s case. Gord Miller’s report cited an operation in the North Channel where oxygen was all but absent from the water, a situation blamed on bacteria feeding on waste from the farm. Moccia counters that research has since come to light showing that low oxygen levels in the area predate the farm and are cyclical in nature, but past bad practices sometimes haunt the current industry, reminding critics of what could happen if the industry is poorly regulated or allowed to over-expand without sufficient oversight; if businesses start cutting corners because of financial pressures or fail altogether and leave a mess behind in public waters.

One stain on cage aquaculture’s reputation is a recent study Environment Canada conducted at a former fish farm that operated through much of the nineties near Great La Cloche Island. From 2000 to 2007, the study monitored the recovery of this site. The water is only 12 to 20 metres deep, and the researchers found bottom deposits of fish feces and food waste up to a metre thick directly beneath the cage locations.

The industry considers that operation an anomaly, the result of outdated practices and a poorly chosen location. At Lake 375, a deposit of 18 centimetres accumulated over five years in similarly shallow water. “There have been quite significant gains in production technology, in feed formulations,” says Moccia. Even so, the GBA wants to see bonds posted by cage aquaculture operations as part of their condition of licence, in order to pay for any necessary environmental remediation.

“Our environmental impact is related to quantity and quality of feed,” Cole explains. While licences are intended to limit waste by capping how much feed a farm can employ, the actual quantity of waste is highly dependent on the quality of that feed, says Cole. “We’ve reduced waste production, solid and dissolved, by 80 to 90 percent simply by changing the feed formulation.” Fallowing – moving cages around – further reduces waste accumulation; in summer, Aqua-Cage’s pens are moved a short distance out into Parry Sound, into 200 feet of well-circulated water.

Cole argues that the surrounding environment benefits from his operation. “Fish [excrement is] being eaten either directly by small fish or by various invertebrates.” He believes that his operation deserves some credit for the rebound in lake trout numbers in the sound, a rare occurrence in Ontario, and for raising the total amount of sport fish for recreational fishers.

Cole believes Podemski’s research tentatively supports his claim. She conducted a study of bottom sediments beneath Cole’s cages (as well as at five other Ontario cageaquaculture facilities) and, while she cannot vouch for Aqua-Cage increasing sport fish numbers, she reports that “we saw a high abundance of benthic invertebrates close to the farm’s cages. Those invertebrates can be an important food source for some wild fish.” The Ministry of Natural Resources has reported a rebounding of lake trout in Parry Sound, and while Podemski won’t draw a positive link between cage aquaculture and lake trout health, the DFO says, “Even though the [Lake 375]cage site is close to a laketrout spawning area, the researchers have seen no adverse impact. Estimates suggest that the lake trout population in Lake 375 has increased. Podemski does note that “Lake trout are growing faster since we started the cage aquaculture study. They’re sexually maturing earlier, and their condition factor, or ‘fatness,’ which is [a] good [quality] in fish, is much higher than we have observed.”

Miller’s report raised the prospect of escaped farm fish harming genetic wild stocks. Since the provincial government’s regulatory regime requires that a cage operation raise only fish native to its location, genetic contamination is a legitimate concern. Moccia says the issue, practically speaking, is a red herring, because only rainbow trout are being raised commercially, and he notes that there is no such thing as an indigenous “wild” rainbow trout population. The species was introduced to the Great Lakes in the late 19th century and is considered “naturalized”; ongoing stocking programs support its numbers. Harming its genetic diversity,
Moccia says, is a “non-issue.”

One of the biggest criticisms of cage aquaculture is the risk of farmed fish introducing new diseases to wild species. The threat was highlighted last year, when Minnesota’s Department of Natural Resources allowed 2,000 trout to be imported fro m Wisconsin to stock a private pond. The trout were later discovered to have come from a hatchery whose fish had infectious pancreatic necrosis (IPN), a disease not yet seen in fish in Minnesota. The state, which has one of the most rigorous fish protection regimens, spent $11,000 to kill and bury every single trout from the private pond in an effort to prevent IPN from spreading elsewhere.

In Ontario cage aquaculture relies on hatcheries to screen fingerlings to ensure that diseased fish are not introduced to fish farms. Operators are permitted, with the supervision of a veterinarian, to treat sick fish in open cages with antibiotics and other pharmaceuticals. Operating licences require that incidents of infection with specific diseases be reported to the Ministry of Natural Resources. Under the provincial government’s draft guidelines for cage aquaculture licensing, farmers would not have to report fish deaths until they exceeded 1,000 per day.

Rich Moccia of the Aquaculture Centre at the University of Guelph argues that cage aquaculture farms must live up to a “stringent inspection and fish-health standard,” including the maintenance of health histories – something lacking for aquarium fish, for example.

Moccia further argues that farm fish are not the main threat in terms of disease. “Wild fish pose a greater risk to farmed fish.” He notes that viral hemorrhagic septicemia, a virus that has killed many fish throughout the Great Lakes, did not arrive through aquaculture.
Douglas Hunter

Miller’s report also maintained that the risk of genetic harm to wild species “is magnified when the farmed species are genetically modified.” Moccia rejects that concern. “No sector of the aquaculture industry in Canada uses genetic modification, except through normal breeding programs at hatcheries that select for desirable traits. There’s no place in the world that’s trying to achieve rapid growth through true genetic manipulation.” That said, DFO does conduct biotechnology and genomics research in support of aquaculture, particularly in the areas of brood stock selection and disease research. The agency states on its website: “For the record, no genetically engineered fish have been approved for commercial use, consumption or release in Canada.” Those concerned about genetic modification will have to be sure that things stay that way.

Cole, for one, has long argued that cage-aquaculture operations should not raise any species of which escapes (which are inevitable) could affect the wild genetic stock. On this point he disagrees with the draft provincial guidelines, which would continue to allow the farming of such native species as bass and muskellunge. “We need to avoid introducing new species but also avoid growing a species where it already exists and could [cause] problems of cross-breeding through escapes,” says Cole. He believes rainbow trout are ideal for Great Lakes cage aquaculture because government-approved stocking programs sustain them. In fact, Cole gets his fingerlings from a hatchery that supplies MNR for stocking. If MNR is releasing the same genetic stock into the wild, then occasional escapes from Aqua-Cage should not be an issue.

While critics push for the elimination of cage aquaculture, that is not what Ottawa wants. In last year’s budget, the federal government announced $70 million in funding for the industry over five years, aimed at streamlining regulation, strengthening the science and making the sector more competitive internationally.

As the oceans continue to be depleted, much of the world has been turning to aquaculture as a solution for harvesting fish, and as a new source of employment. These efforts have not always produced happy environmental outcomes, causing everything from water pollution to the depletion of ocean species such as anchovy to be used in fish feed for aquaculture. Avoiding or minimizing environmental impacts going forward is a major challenge. The MNR draft guidelines require that no cage aquaculture operation negatively impact a species (or its habitat) that is on the provincial or federal species-at-risk list.

Meanwhile, the European Union recently indicated its interest in promoting its aquaculture industry, but that is producing pressure to diminish interference from the EU’s own Habitat Directive, which requires proposed aquaculture operations prove they will not harm local environments and protected species.

In Ontario, Rich Moccia thinks cage aquaculture deserves to thrive. “Technological advancements have caused an almost exponential change in everything from feeding systems to environmental protocols. And people have to eat. We have to farm fish somewhere.” Maybe, but it won’t be in open cages on Georgian Bay or the North Channel, if the GBA has anything to say about it.


douglas_hunterDouglas Hunter is the author of God’s Mercies: Rivalry, Betrayal, and the Dream of Discovery. He has previously written articles for ON Nature on cougars, cormorants and the impact of climate change on Ontario’s biodiversity.

1 Comment

  1. Gintas Kamaitis Gintas Kamaitis
    October 10, 2009    

    As someone who has worked within the Ontario aquaculture industry for many years; and has worked with the GBA’s Aquaculture Committee this is a very balanced article. One of the main challenges we have is that with the introduction of exotic non-native species such as zebra mussel and the resulting dramatic changes to aquatic food web and Great Lakes fisheries it is difficult to assess the potential impacts of nutrient additions from cage farms. I do not doubt Gord Cole’s claims of helping to improve the local wild fishery are true. At the same time we need to be vigilant of the potential for lake wide impacts from a rapidly expanding industry. Moderate expansion with the long term objective of solid waste recovery through the use of closed containment technology would appear to be a prudent long term strategy.

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