Skip main navigation

Genetics and disease: case study on the impact of farmed hatchery on wild salmon stocks

In this step, the FoodUnfolded® team collaborated with Hakai magazine a magazine exploring science, society, and environment.
© Hakai Magazine

In this step, the FoodUnfolded® team collaborated with Hakai magazine, a magazine exploring science, society, and the environment in compelling narratives that highlight coastal life around the world. They practice journalism in the public interest and publish all of their stories exclusively online, for free.

This article includes a shortened version of the full written and audio article, available in the See also section at the bottom of this page.

The hatchery crutch: how we got here

Across much of the Pacific Northwest of North America salmon populations are struggling. An array of modern plagues—development, pollution, logging, overfishing—has decimated habitats, leaving fish gasping for oxygen, searching in vain for egg-friendly gravel, and swimming smack into concrete barriers as they return to their home rivers and streams. And yet, there are more salmon in the North Pacific Ocean than there were a century ago.

More fish has been a rallying cry in the region—often referred to as Salmon Nation—since the late 1800s. But to reach that goal, the trade-off has been ruinous for the salmon: we’ve got fish, but not a lot of habitat.

Cannery operators in Oregon built the first salmon hatchery on the west coast to supplement their catches in the late 19th century. At least 243 hatcheries are strung along salmon habitat from California to Alaska and more feed fish into the North Pacific via hatcheries in Russia, Japan, and South Korea. Annually, since 1988, the five—including Canada—salmon-producing countries release over five billion hatchery salmon.

Most hatcheries are industrial affairs. Eggs and sperm first meet in white plastic buckets and are released after some months of growth. They crowd degraded streams, competing with wild fish for food and safe havens. Later in their lives, hatchery fish enter spawning grounds and interbreed with wild salmon, diminishing their genetic robustness. And, like boats, hatchery fish are money pits. The cost of salmon varies per hatchery, but 20 years ago, a researcher calculated that to keep hatchery salmon in swimming the Columbia and Snake River basins in Oregon, Washington, and Idaho, the price tag was US $400 per fish.

We’ve known for a long time that hatcheries are no solution to diminishing salmon runs. By the early 1930s, the science had already aligned against fish hatcheries. Why did we abandon the restoration and protection of salmon habitat and instead lean so heavily on hatcheries for fish?

At first, it was mainly politics and blind faith in technology. Today, the reliance on hatcheries is a combination of politics, law, and desperation.

A brief history

Almost a century ago, a Canadian scientist revealed that hatcheries were at best failed experiments and at worst monuments to delusional thinking. In the early 1920s, fisheries biologist Russell Earl Foerster arrived at Cultus Lake, which drains into the lower Fraser River in British Columbia, to run a salmon hatchery built by the province 10 years earlier. He established a research station as well. Foerster had a few questions, including whether raising fish in hatcheries worked: were the wild runs of salmon at Cultus less or more productive compared with the hatchery fish raised at a creek downstream of the lake?

Without any evidence that playing God with fish was a good idea, hatcheries had proliferated across the Pacific Northwest after the US government built the first national hatchery in 1872 in California. Canada built its first west coast hatchery in 1884. Salmon runs were already diminishing, but there was no political will to protect or restore habitat: fisheries managers declared artificial spawning the price of progress, an economic journey measured in dollars, mostly benefiting the few who ran timber companies, mining operations, and canneries. When the University of Washington (UW) launched a fisheries department in 1919, students studied canning technology and fishing methods. It took 10 years for the focus to switch to biology and conservation.

Foerster’s 12-year experiment comparing hatchery sockeye and wild runs became a classic in the field of salmon research. He showed for the first time—in a published scientific paper—that in the early stages of salmon development, most fish die as prey to bigger fish, raccoons, ducks, and other predators.

Foerster also found that artificially fertilised eggs hatched at higher rates than naturally fertilised eggs. And he determined that when hatchery managers incubate and release fry, juvenile salmon flood a stream. More fish! But more fish going down the river was no guarantee they’d find their way home again. Over the years, we’ve come to know that hatchery salmon often lack the skills to navigate life the way a wild fish does, learning life lessons like what to eat—not all tiny things in the water are edible—and that a dark head against a light sky could be a killer. The early advantage for hatchery fish, Foerster showed, failed to hold. What, then, was the point of spending money on artificially raising and feeding salmon?

By 1934, understanding that running a hatchery was about the same as tossing cash directly into the ocean, the Canadian government decided against them and federal hatcheries closed in 1937. Alaska closed its hatcheries, too. The fiscal restraint was admirable, but it was also a lot easier to close hatcheries where spawning habitat remained relatively intact, in British Columbia and Alaska.

Farther south, a mishmash of jurisdictions, a cozy relationship with industry, and a larger population clamouring for more development and more hydroelectric power cemented hatcheries as the fisheries policy of choice. Those early hatcheries were a political panacea: fish culture emerged as a default solution to a problem around the politics of land use.

But by the 1960s, hatcheries had stuck around long enough for managers to be lulled into thinking technological improvements—new drugs to control disease, better feed—would make the next wave of hatcheries the best thing in fisheries since the invention of the boat engine. But really, it’s more like a stubborn belief that salvation lies in technology, and that trumped good old-fashioned conservation.

Salmon enhancement

In 1974, Peter Larkin, the first provincial fisheries biologist in British Columbia, wrote an influential essay, “Play It Again, Sam—An Essay on Salmon Enhancement,” that’s equal parts enthusiastic and skeptical. Larkin spells out the foibles humans might bring to hatcheries and other means of boosting fish populations: the lack of continuity in research, the lack of true experimentation, and muddy goals. But, as Larkin notes, “Politically, salmon enhancement is a ‘natural.’” The other option was to stop catching salmon.

Larkin called salmon enhancement a gamble, but one worth taking. Canada reversed its earlier decision and gambled that technology could restore populations and double the annual commercial catch by 2005, launching the Salmonid Enhancement Program (SEP) in 1977. They funded hatcheries and spawning channels and fertilised lakes and streams to promote the growth of fish food. In the early 1980s, the University of British Columbia hired Ray Hilborn, today a well-known fisheries scientist at UW, with funding provided by the SEP. “It was a total failure,” Hilborn says of the program. The catch went down. By 2005, the commercial catch had almost halved from 1970s levels, at 31,811 tonnes, or 54.6 percent of the average. By 2019, the catch was 3,423 tonnes, or about five percent of the catch 42 years before.

Alaska, like British Columbia, revisited its hatchery policy in the 1970s amid salmon declines, and officials there also decided the time had come to invest in salmon enhancement. It was a similar story in Washington State. Already dotted with hatcheries, the state launched a program to double the salmon harvest a year after SEP began. Runs were on the decline, and again, reducing fishing pressure is never popular even if it’s the right thing to do. Plus, a series of court rulings that gave Indigenous communities back their rights to fish apparently panicked fisheries managers: the state poured US $30-million into tribal programs over more than 10 years. Tribes built their own hatcheries to guarantee access—enshrined in treaties and through the law courts—to salmon. These hatcheries keep Indigenous cultural practices and salmon populations alive as tribes embark on the hard work of restoring habitat.

A big picture view, however, shows that Larkin’s advice to avoid past mistakes was often disregarded. As Hilborn notes today, and in many research papers in the past, ideas around monitoring outcomes and specifying clear, measurable goals fail to stick when it comes to many hatcheries and other salmon enhancements. By 1994, an economist concluded that the economic costs of the SEP would exceed the benefits by CAN $600-million.

Even though salmon catches increased between the 1970s and 2010s, geographically there are winners and losers. Russia’s total catch increased by 4.9 times, and the US catch, mostly in Alaska, went up 2.6 times. In Japan and British Columbia, catches decreased, regardless of whether fishers were harvesting wild or hatchery salmon. (Japan’s catch is almost entirely hatchery chum salmon.)

As for the fish species in this age of hatcheries, there are literal winners and losers. In a 2018 study, fisheries scientists Greg Ruggerone and scientist Jim Irvine shocked those who pay attention to salmon with the fact that the North Pacific hosted more salmon in 2015 than in 1925, when Foerster was at Cultus Lake. “But the problem was, nearly 70 percent of those fish were pink salmon,” Ruggerone says. In 2018 and 2019, more pinks returned to spawn than any year the scientists studied, causing trouble for other salmon species.

Over a 15-year time frame, Ruggerone and his colleagues found that hatchery chinook from Washington State saw a 60 percent reduction in survival in the years they compete for food with the pinks. Manufactured pinks are fighting it out in the ocean with wild fish—and competing with other hatchery fish that may have a better reason for being there. Conservation hatcheries sometimes offer the last hope for particular runs of fish: for instance, Russian River coho in northern California, Snake River fall chinook in Idaho, and Okanagan River sockeye in British Columbia. Those conservation efforts—paying attention to genetics, using locally adapted broodstock, raising juveniles in enriched environments, among others—are paying off, though barely for Russian River coho. A whiff of desperation haunts hatcheries.

Restoring salmon population

Salmon Nation finds itself in a predicament with no clear way forward. Here we are today, with an upended environment, too many fish, and not enough habitat. But we have the grim duty to look around, take our bearings, and say, “Well, where do we go from here?”

As Larkin wrote, clear goals are important. To restore salmon populations requires a thoughtful, long-term vision. Habitat restoration is key, and in some instances a conservation hatchery that keeps distinct salmon populations alive during the long process of undoing extensive damage to watersheds. Also, policies that separate hatchery fish and wild fish could give the fish more breathing room in their habitats.

To cleave apart wild from hatchery fish, and the different populations, would mean a fundamental shift in the style of commercial fishing, moving toward terminal fisheries, in which weirs or traps, rather than hooks and nets, catch fish in the river on their way home to spawn. Once standard practice from Alaska to Northern California and in Japan and Russia, weirs allow for more targeted fishing. With weirs, fishers can aim for hatchery fish, identifiable by a clipped adipose fin. An experimental fish trap near the mouth of the Columbia River in Oregon is a new take on the old technology, guiding fish into a trap where they can swim freely, and fishers can select which fish to harvest. The Lax Kw’alaams First Nation on British Columbia’s north coast has proposed fitting a fish trap on the Skeena River, where an abundance of hatcheries and artificial spawning channels has led to lower salmon diversity.

None of those solutions, however, addresses the disease or competition issues. Nor can anyone control the ocean. But managers can control hatchery fish.

Right now, there is no shared vision across the five countries on the role of hatchery fish. Randall Peterman, a fisheries scientist and professor emeritus at Simon Fraser University, has called for international cooperation since the early 1980s.

Almost 40 years ago, Peterman and his colleagues had already noted the competition between salmon populations in the ocean. BC sockeye came back smaller and less abundant in years when the Bristol Bay, Alaska, sockeye were abundant. Any efforts at enhancing sockeye populations were a classic case of the law of diminishing returns—the effort and money sunk into enhancement did not translate into consistently more fish.

“So this is not a country-specific problem. It’s an international problem,” Peterman says. “We need to be thinking in those terms. You can’t continue to pump out fish into a common pasture—the ocean—and expect continuous commensurate benefits.” Peterman muses about a cap-and-trade system, similar to the one used by British Columbia to control carbon emissions.

Salmon hatcheries are the sum of poor choices made over 150 years by policy makers and managers, often having no idea what they didn’t know about salmon, habitat, and the ocean. Magical thinking is no substitute for humility. Even Larkin, when making a case for salmon enhancement, wrote: “but natural systems being what they are, there is always a good chance that our best efforts will turn out to do more harm than good.”

The number of hatchery fish outmuscling wild in the North Pacific is not catastrophic. Not yet. The proportion of pink hatchery salmon, for example, is only 15 percent of the total pinks in the North Pacific, but what if that percentage grows? Fisheries managers have faced political and economic pressures countless times in the past. Managers don’t act soon enough and then the crisis is upon them. “And then finally they act, but it’s often too late,” Peterman says. “Here’s a case where we can get in sooner than usual. We just need to get ahead of this one.”

Author: Jude Isabella for Hakai Magazine

© Hakai Magazine
This article is from the free online

Sustainable Seafood: Barriers and Opportunities in the Fishing Industry

Created by
FutureLearn - Learning For Life

Our purpose is to transform access to education.

We offer a diverse selection of courses from leading universities and cultural institutions from around the world. These are delivered one step at a time, and are accessible on mobile, tablet and desktop, so you can fit learning around your life.

We believe learning should be an enjoyable, social experience, so our courses offer the opportunity to discuss what you’re learning with others as you go, helping you make fresh discoveries and form new ideas.
You can unlock new opportunities with unlimited access to hundreds of online short courses for a year by subscribing to our Unlimited package. Build your knowledge with top universities and organisations.

Learn more about how FutureLearn is transforming access to education