Skip to main content
Bridge Michigan
Michigan’s nonpartisan, nonprofit news source

Battle building over fish farming in Great Lakes

In 1982, a Canadian named Gord Cole built a Norwegian-style fish cage on the far eastern end of Lake Huron, in Parry Sound. He said he believes it was the first use of this technology in fresh water to produce fish for food, and that it may be the oldest continuously operated fish farm in North America.

A handful of producers followed Cole’s lead, many in Huron’s North Channel, around Manitoulin Island, and a modest industry sprang up in the province that today produces about $16 million worth of rainbow trout annually, which are sold to restaurants and groceries. But it’s an industry that’s now highly regulated, after waste from fish pens was found to starve water in the LaCloche Channel of oxygen and contribute to algae blooms.

No U.S. state has followed Ontario into this type of farming on the Great Lakes. But now a policy debate is underway in Michigan about whether to open the Great Lakes to farming operations. A report produced by Michigan Sea Grant last year suggested a billion dollar industry is possible.

Supporters of the idea say Michigan is perfectly positioned to be a world leader in freshwater aquaculture and home to all the science, engineering and manufacturing that would accompany this growing part of the world’s food economy. But critics counter that the Great Lakes is no place for so-called net-pen fish farming because of the higher risk of disease and water pollution that accompanies this method.

Environmental groups and sport anglers have come out against it; even one of the few fish farmers in Michigan ‒ Russ Allen, who grows shrimp in an indoor facility in Okemos and is on the board of the Michigan Aquaculture Association ‒ says the Great Lakes is no place for net-pen fish production. Net-pen fish farming is considered to have a higher environmental impact than other methods because fish waste is allowed to flow freely into the surrounding water.

“There is good aquaculture, and there is bad aquaculture,” Allen says. “Net-pen aquaculture in the Great Lakes is bad aquaculture.”

The main problem with these farms is having so many fish pooping in one spot. Allen says that lakes are unforgiving compared with oceans, where tides can wash the fish waste away. He says when things go wrong, like in the LaCloche Channel, the changes in the lake will be slow to heal.

Last year, controversy erupted in Michigan when a trout farmer in Harrietta, near Manistee, proposed expanding production at the Grayling Fish Hatchery. The farm in Grayling sits alongside the Au Sable River just above a stretch known as the “Holy Waters”; water that flows through where fish are raised empties out in the river.

Dan Vogler runs the county-owned hatchery as a historic site for tourists and produces a small number of rainbow trout. His plan to go to a commercial scale (from less than 20,000 pounds of fish annually to hundreds of thousands of pounds) upstream from the most revered stretch of trout water in Michigan has drawn scrutiny and legal challenges from the Sierra Club and Anglers of the Au Sable, a conservation group. [Disclosure: Center for Michigan CEO John Bebow is an officer and board member of Anglers of the Au Sable; he had no role in the reporting or editing of this report]

Great Lakes or go home

In the background has been a conversation about cage farming in the open waters of the Great Lakes. Quietly promoting that idea has been a man named Kent Herrick, who is both a trustee with the Michigan chapter of the Nature Conservancy and a board member of the Mackinac Center for Public Policy, a conservative Michigan think tank.

Herrick sees pen farming as a way to help compensate for the decline of manufacturing in the state. In turning away from heavy manufacturing, Michigan “made a conscience decision we’d rather have clean waters, clean rivers, and have this pristine land,” he says.

Herrick contends a major fish producing industry could fit comfortably in the state’s water economy, help feed the world, and not conflict with the popular vision of a “Pure Michigan.” He said the state’s strong regulatory regime and academic institutions would allow fish farms to prosper and not cause problems. Until recently, he ran a small indoor aquaculture system in Tecumseh and experimented with perch.

But Herrick said commercial fish producers will need the Great Lakes for the industry to reach a scale that’s sustainable. Without it, he sees smaller land-based operations, like Dan Vogler’s, facing an uphill climb to build a stable supply chain. The Canadians, he says, have reached that threshold.

“Trucks come north from southern Ontario up to Parry Sound and Manitoulin carrying a truck full of feed and they’ll return that same day with a truck full of fish to be processed and delivered into the major markets, like Toronto,” he said.

To reach a viable scale, Herrick said the industry in Michigan needs to be more than half the size of that in Canada. That would mean at least five or six rainbow trout farms in the Michigan waters of the Great Lakes.

But even groups that see the value in a fish farming industry draw the line at the Great Lakes. There are other places to build fish farms, like alongside streams, in abandoned quarries or even indoors in warehouses, these critics say. These inland facilities allow more control over the fish waste because it can be captured and even used as fertilizer.

There is no way to capture fish feces from an open water farm, and Sean Hammond from the Michigan Environmental Council says the risks aren’t worth it. For that reason, Hammond argues that cities with abandoned warehouses like Detroit or Flint are a far better place to develop a fish farming industry.

“That’s where we see a great potential for recirculating aquaculture growth,” he said.

Learning from Ontario

In addition to fish waste, there are also concerns about diseases and even genetics because farmed fish can escape and breed in the wild. A science panel was formed by Michigan earlier this year to look into these matters and is expected to issue a report in October.

Of all the doubts about pen farms, the question of fish waste has been the most discussed and is likely to be most contentious.

Fish waste contains phosphorous. The nutrient is essential for any ecosystem, but too much leads to problems like the ones experienced in Lake Erie, where excessive nutrients caused widespread algal blooms the past few summers and even created enough toxins to make Toledo’s drinking water unsafe last year.

ADDITIONAL COVERAGE: “Algae bloom, the sequel, spells big trouble for Lake Erie”

But advocates for commercial farming note that lakes Michigan and Huron are not like Lake Erie. In fact, parts of the upper Lakes are considered nutrient poor and Ontario fish producers will argue that their operations, and the waste that comes with them, can improve fisheries in these areas. At a conference in St. Ignace in August, Gord Cole credited himself with the restoration of lake trout in Parry Sound. (Lake trout have recovered across Lake Huron in the past decade.)

Cole argues that phosphorous that comes off a fish farm does not end up dissolved in the water in significant amounts but is mostly solid and eaten by minnows and other organisms that in turn can be eaten by larger fish. He says he has been testing the water around his fish cages for years and not been able to detect any difference.

“And I spend about $15,000 a year doing phosphorous tests,” he says.

Provincial officials that regulate Ontario trout farms have been largely absent from the discussion in Michigan so far and unresponsive to media inquiries, making verification of these claims difficult. In response to an email seeking comment, an official from the Ontario Ministry of Natural Resources said the department is considering some applications for new farms and the issue is “complex” because of water-quality issues, among others. Nobody was available to discuss those complexities.

There has not been much published research on the danger these commercial farms pose to the Great Lakes. After the first 20 years of the Canadian experience in Lake Huron, there was just one published report on fish farms and water quality.

Cole contends that there has been plenty of research but it hasn’t been published because scientists aren’t finding any problems.

A seascape of pens

Fish farming advocates have great ambitions for the Great Lakes.

The Michigan Sea Grant Report was written by and with support from promoters of the aquaculture industry. It suggests up to 5,000 acres of the Michigan waters of the Great Lakes could be used to farm fish. Both critics and proponents of the idea have cited this number to show how large or small the proposed industry could be.

Cole seemed to make it a moot point when he visited Michigan last month and announced he didn’t see many sites at all on the Michigan side of the lakes that would be suitable for rainbow trout farms. He says that net pens need protection from the open water and was doubtful there are more than a handful of places that would work.

“There are very, very strict requirements,” he said.

But a handful of farms might be all that is needed to spark a large-volume industry in Michigan, according to Herrick.

Herrick sees some farming in the near shore waters of the Great Lakes as essential to building a base for the industry. Once that’s established, he said, other types of farms, in abandoned quarries or warehouses, would be more likely to succeed financially and the industry could grow in other ways. His bet is that eventually indoor systems, already preferred by conservationists, will advance and also become the preferred method of the aquaculture industry in Michigan.

Critics of the aquaculture industry are less than convinced by the assurances of Canadian farmers and other proponents that all is well. Mark Ebener is a fisheries biologist with the Chippewa Ottawa Resource Authority, an agency based in Sault Ste. Marie that supports the commercial fishing efforts of five Michigan tribes.

The tribal perspective could have considerable weight on this debate since the tribes have treaty rights to fish in broad swaths of lakes Huron and Michigan, rights that cannot be limited by Michigan, according to a federal court ruling from 1979.

Ebener said he is particularly concerned that one location being discussed for cage pens in Michigan is in the Little and Big Bays de Noc in northern Lake Michigan. He says these are among the most fertile spawning grounds in Michigan for native species like perch, walleye and whitefish. Whitefish are critical to the tribal fishing economy.

Ebener concedes he does not know what impact aquaculture would have on this area.

“But I do know the aquaculture industry has no idea, either,” he told Bridge in an email. “If they really do want to institute ‘best management practices’ then it seems to me that they must prove their actions will not harm the perch, walleye, and whitefish population and fund studies to test that.”

Peter Payette is news director at Interlochen Public Radio and has been reporting on the debate over fish farming in the Great Lakes. He can be reached at

How impactful was this article for you?

Only donate if we've informed you about important Michigan issues

See what new members are saying about why they donated to Bridge Michigan:

  • “In order for this information to be accurate and unbiased it must be underwritten by its readers, not by special interests.” - Larry S.
  • “Not many other media sources report on the topics Bridge does.” - Susan B.
  • “Your journalism is outstanding and rare these days.” - Mark S.

If you want to ensure the future of nonpartisan, nonprofit Michigan journalism, please become a member today. You, too, will be asked why you donated and maybe we'll feature your quote next time!

Pay with VISA Pay with MasterCard Pay with American Express Pay with PayPal Donate Now