Wild salmon may not be as wild as you think


Thumbnail for 560Alaska uses hatcheries to boost their stocks — but there may be risks

When it comes to sustainable seafood, Alaska’s wild salmon is unquestionably one of the best choices out there for conscientious eaters. But questions are mounting over just what counts as wild.

Today, a third of all salmon harvested in the state of Alaska — a whopping 58 million of them — are what are known in the industry as “hatch and catch.” Fully-wild salmon start life in a cool, gurgling stream, in a depression its mother formed by her wriggling. Instead, these salmon begin life in one of the state’s 31 hatchery facilities, where they’re bred from captured local broodstock, hatched, fed, and raised for two to three months (some as long as a year) before being released into the wild.

A third of all salmon harvested in the state of Alaska are “hatch and catch”

But there’s growing concern among scientists and environmentalists over the Alaska’s enhancement program for wild salmon. Worries over straying hatchery salmon, competition for food at sea, overharvesting of wild salmon in mixed stocks, and genetic fitness of hatchery-bred fish are gaining attention, prompting the state’s regulators to take a closer look at practices that have been in place for over 40 years.

Although most consumers of wild salmon aren’t aware of the state’s use of hatchery fish to supplement stocks, it isn’t a secret. Alaska’s hatchery program stretches back to the early 1970s and, from the beginning, was carefully planned. Hatcheries were intentionally placed away from large natural production areas, in spots where returning fish could be harvested separately from wild stocks. Each year, the Alaska Department of Fish and Game provide lawmakers and the public with updated reports detailing things like number of egg takes, releases, and adult returns, while wild stock numbers are continuously monitored.

Alaska is the largest producer of hatchery salmon in north America

Today, Alaska is the largest producer of hatchery salmon in North America, releasing about 1.6 billion juvenile salmon into the wild each year; it’s second only in the world to Japan, which releases approximately 2 billion fish a year. According to the 2014 Alaska Salmon Fisheries Enhancement Program report, in some parts of the state, hatchery fish make up the majority of the catch. In Prince William Sound, for example, 45 million salmon returned from hatchery releases, including 93 percent of the commercial catch of pink salmon, and 68 percent of the chum. In Southeast Alaska, 85 percent of the commercial chum catch started life in a hatchery, as did 27 percent of the commercial coho catch. And now, new studies are raising concerns that these millions of hatchery-raised salmon may in fact be harming wild salmon and other species, including young seabirds, after all.

We now know not all hatchery fish return to the exact streams where their lives began. Salmon sometimes stray. As far back as 1991, after the Exxon Valdez spill, hatchery fish were discovered in streams where they didn’t belong.

sockeye cluster

A mob of spawning salmon in Bristol Bay. (USEPA)

“That was the first we saw them straying into other streams,” said Jeff Regnart, director of the Division of Commercial Fisheries for the Alaska Department of Fish and Game at a conference in February. “Later, we found that was continuing for pink and chum salmon, and that has given us pause. We want to understand if it’s going to have a fitness impact on wild populations. Our job is to protect wild salmon.”

What makes Alaska’s hatchery enhancement program different than those in Japan or Russia is the state is not using hatchery-bred fish to restore natural stocks lost to development or overfishing.

Greg Ruggerone, a salmon scientist with Natural Resources Consultants, a company specializing in fish ecology and fisheries management, says he is most worried about interbreeding of wild and hatchery fish.

“The biggest issue and the one that’s raised the greatest concern over the decades has been genetic issues — interbreeding of hatchery and wild salmon in spawning grounds,” says Ruggerone. “When hatchery fish interbreed with wild fish, it confounds our interpretation of the wild stock, making it hard to evaluate.”

“Our job is to protect wild salmon.”

But Ron Josephson, the section chief of the Alaska Department of Fish and Game, says they are diligently monitoring areas with mixed stocks.

“If [scientists] find out hatcheries are impacting wild stocks, we’ll have to decide what action to take. These are decisions down the road. It depends on the magnitude of the effect. It’s hard to imagine it’s too large, or we would have seen it in areas like Prince William Sound or Southeast Alaska,” he says.

The state is in the third year of a 12-year Hatchery Wild Interaction Study looking at genetic and ecological interactions between hatchery and wild salmon and any impacts that may have on wild stocks.

“We’re now able to do family tracking through genetics,” says Sam Rabung, who is the PNP Hatchery Program Coordinator.

Today, scientists are able to identify the progeny from two salmon that spawned in a natural system. Or identify hatchery fish that spawned in the wild with another hatchery fish, or if it bred with a fully-wild salmon. And, they can identify their offspring, and whether or not those salmon came back to their spawning grounds at the same rate. “It’s remarkable,” says Rabung.

The numbers are massive — 58 million returning hatchery fish last year alone — which explains why straying of hatchery fish into wild populations and spawning grounds is a growing concern.

“If 1 percent of fish naturally stray, and 93 percent are hatchery salmon, that’s a big impact on the natural population in terms of sheer numbers,” says Randy Ericksen, the fisheries science director at Ocean Outcomes, a not-for-profit that studies global fisheries.

Straying isn’t the only the only worry. Generations of returning hatchery salmon could change the timing of natural salmon runs, warns Ericksen. And nuances in salmon, even within the same species, aren’t always controllable in hatchery breeding programs.

“There are differences even in fish that return to the same river,” says Ericksen. “Some sockeye, for example, specialize in spawning in rivers, others in tributaries, and others on beaches. You can look at them, and they can even be physically different, but they’re all sockeye.”

Hatchery enhancement is very much on the radar of the Monterey Bay Aquarium’s Seafood Watch program, which provides sustainable seafood recommendations to consumers. Wild Alaskan salmon (including hatchery fish) still merit a “best choice,” but the group is in the midst of updating its salmon standards.

“The concerns we’ve been looking at are mainly interactions between hatchery fish and wild fish,” says Sam Wilding, a senior fisheries scientist at Seafood Watch. “Over the last five years, there’s been more science looking at impacts. But what we don’t want to do is to put something in our criteria that says this is a concern, but we have no way to measure it. You have to be able to measure. Hopefully that will incentivize greater research.”

The use of hatcheries to enhance stocks has been a point of contention between the salmon industry and the Marine Stewardship Council, the world’s largest wild seafood certification program. MSC’s greater scrutiny of hatchery salmon are now being addressed in new standards went into effect April 1st, and for the first time, spell out how salmon enhancement activity will be measured.

“Our natural system is finite.”

“The requirement is that enhancement does not negatively impact wild stocks,” says Megan Atcheson, an assessment manager at MSC.

While Alaska takes a closer look at its hatchery program, don’t expect enhancement practices to go away anytime soon. Hatchery salmon provide additional harvestable fish and important economic benefits to the state.

“Our natural system is finite. The only way to produce more harvestable fish is through our hatchery program,” says Rabung.

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