Building a Better Fish Trap

Story by Megan Hill

The Columbia River’s once-epic salmon runs are in trouble. The solution could lie in the revival of a millennia-old method of fishing called a fish trap.

Last year on the Columbia River, the historically epic salmon migration was a trickle of its former self. 

In the fall, Chinook numbers at the Bonneville Dam barely hit 30 percent of the preseason forecast, leading the Washington Department of Fish & Wildlife shut down fishing on much of the river. It was the same story earlier in the year, with significant reductions in the number of spring Chinook and coho salmon returning upstream. Overall, 2018 was one of the worst wild Chinook runs in history in the Columbia River and its tributaries. 

That meant fewer Columbia River salmon on plates around the Northwest, but also — perhaps more infamously — fewer fish in the bellies of the region’s beleaguered southern resident killer whales. In late July, an orca known as J35, or Tahlequah, gave birth to a calf that died within half an hour. The mother captivated the world by carrying her dead calf on her head, through Puget Sound and the Salish Sea, for 1,000 miles over 17 days. Her agonizing display brought attention to a host of interrelated issues plaguing these whales. Their struggle is linked in part to the dwindling number of Chinook salmon, caused by over-fishing and environmental degradation.

The Columbia River was once a legendary fishery, revered first by native people and later by white fishers, especially during the early runs of Chinook, or king, salmon. These fish head far up river to spawn, but they don’t eat once they leave the salt water, so they need huge fat reserves to get them through their months-long ordeal. The tribes living along the Columbia River traded these fatty, flavorful fish across the region, spreading their legacy far and wide. 

Today, the story of salmon in the Columbia River and its tributaries, like the Snake, could not be more different. The state of wild fish there is dire: 13 stocks (seasonally-specific populations such as fall Chinook) of Columbia River Basin salmon and steelhead are protected by the Endangered Species Act. Those epic salmon runs are a distant memory. Historical overfishing is in part to blame, as are dams that make it hard for fish to move upriver, despite bypass mechanisms like fish ladders.

With salmon numbers so low, fishers must release all wild fish caught in the river — only hatchery fish, those bred specifically for human consumption, can be kept. Some years, there aren’t enough returning wild fish to allow any fishing at all, even if hatchery numbers are healthy. Because most gears are non-selective in their catches, officials can’t risk fragile wild fish populations getting caught, even if fishers are theoretically pursuing hatchery fish. 

The solution — at least in part — could lie in the revival of a millennia-old method of fishing called a fish trap or pound net. Though it’s still being tested for its market viability, fish traps could revolutionize the commercial salmon industry on the Columbia River.

Ironically, fish traps were once reviled on the Columbia, to the point of being outlawed. This gear saw the height of its use during the late 1800s and early 1900s. First developed by Native Americans and used from the Columbia to Alaska, fish traps involve a series of piling-mounted nets that funnel fish into a holding chamber.

Unlike some other commercial fishing methods, which capture fish by the mouth or gills, modern fish traps simply corral the animals into a holding area called a spiller, where there’s flowing, oxygenated water. Next, they’re then lifted into a live well. A wader-clad operator stands in the water to sort the fish, letting undesirable catches — including fragile wild salmon — go free. The fish, whether they’re released or destined for the dinner plate, aren’t harmed during the process and don’t spend more than a second or two out of the water, reducing the stress inflicted by other fishing techniques. 

Fish traps are also incredibly efficient, and they were once deployed in abundance to catch as many fish as possible, with no considerations made for sustainability. When used indiscriminately, a single trap could net a staggering 1.2 million salmon in a single season. The impact was so devastating that, in 1934, Washington voters passed a measure to outlaw fixed-gear fishing methods, including fish traps.

But fish traps, on their own merits, weren’t the reason the salmon population in the Columbia and its tributaries plummeted; they simply weren’t regulated well. In fact, none of the fishing methods in use at the time — from gillnetting to purse seining and beyond — had sufficient oversight to maintain healthy fish populations. 

“There were hundreds of gillnetters out there, there were many traps, there were many seines all operating simultaneously, and it’s kind of a miracle that anything still moves up the Columbia River,” says Adrian Tuohy, a Wild Fish Conservancy biologist and fish trap project manager. “Back then, they weren’t operating fish traps to save fish. The purpose was to harvest as many as possible.”

But now, fish traps are being updated for modern use and finding new life on the river, thanks to the Wild Fish Conservancy, a nonprofit dedicated to reviving wild fish populations. In 2016, with funding from the Washington Coastal Restoration Initiative and the Washington Department of Fish & Wildlife (WDFW), the Wild Fish Conservancy built an experimental, modernized fish trap on mile 42 of the Columbia River. Funding for additional research came in 2017 from NOAA Fisheries, WDFW, and the Oregon Department of Fish and Wildlife. 

Updates to the fish trap help prevent overcrowding, harness energy from solar power, and keep waiting fish away from the hungry jaws of crafty sea lions. Hatchery-born fish can be sent to market, while the wild fish are fitted with harmless electronic tags that track their upriver progress after they’re released. 

For the first two years of the study, Wild Fish Conservancy’s biologists tested to see if this type of gear was even feasible for the Columbia River today. From there, they assessed fish survival rates to determine if it was possible to release fish from the trap unharmed: Could they selectively target hatchery fish and release endangered wild fish unharmed, to aid their recovery?

Adrian says they studied two elements of survival. First, were the wild fish surviving immediately out of the trap? Overwhelmingly, the answer was yes. Second, were the fish surviving long enough to make it up the river to their spawning grounds? While Adrian acknowledges that there’s no perfect detection system to follow the fish for hundreds of miles upriver, the current tracking methods do show that the fish are thriving well past release. 

That’s promising, especially when compared to other fishing methods. The Wild Fish Conservancy tested other gear before installing the fish traps, to see how the results would stack up. Gillnets saw a survival rate of 52 percent for released Chinook salmon; that percentage hit the upper 70s for beach and purse seines and tangle nets, which scoop fish but don’t ensnare them by the gills. 

But fish traps beat them all by quite a margin: Chinook salmon had a 99.5 percent survival rate coming out of the fish traps in 2017; for steelhead trout, the survival rate was an equally impressive 94.4 percent. Those results could be game-changers for wild fish.

That was more than enough to convince Washington State to green-light a test fishery in the 2018 fishing season to see how the traps performed in a commercial setting, to see if fish traps could successfully graduate from a research tool to a solution that actually brought salmon to market.   

The results were well-received. The traps’ processor — the middleman bringing the fish to market — said that “they had never seen fish of that quality — not a scale off the fish, just in pristine condition, no lactic acid buildup from stress and trying to dislodge themselves and then eventually drowning,” Adrian says. 

In 2019, with additional funding, the test fishery is set to continue monitoring results. Wild Fish Conservancy has only tested the gear during the late summer and fall runs; this spring, they’re testing it again to see if they achieve similar survival numbers.

Long term, the Wild Fish Conservancy hopes to build fish traps in other places, too, and it is floating ideas to bring them to Willapa Bay, Puget Sound, and British Columbia. One of the nonprofit’s goals is to expand these projects into fisher-run cooperatives, creating jobs in the process. The cooperatives could also implement techniques used by fishers on the Copper River and off Lummi Island that minimize handling and stress on the fish, thus improving the flavor. The result would be a boutique product that commands a higher price — a boon to fishers and fishing communities. 

More than just jobs are at stake, though. If the project grows, it has serious potential for the recovery of wild fish, which would provide more Chinook for the endangered southern resident killer whales.

The fish traps aren’t exactly welcome news to the river’s commercial gillnetting fleet, the professional fishers who see the traps as a threat to their livelihood. It’s expensive to build a fish trap, and gillnetters have already invested heavily in the gear they currently use. They have questions about whether the expensive traps will yield enough fish to give them a return on their investment. And they may not welcome a cooperative approach when they’re used to being solo entrepreneurs. 

To that, Adrian says, “If you can’t fish at all because the fish are endangered, you might as well have a tool that allows you to fish. I really feel for the gillnetters, but it’s very clear there needs to be an alternative, where you can have a very low impact on these threatened and endangered fish, catch a product of higher quality, and use a gear that’s certified as sustainable. Suddenly, fishermen are in a much better position.” One of the project’s future steps is to work with the state to secure funding that helps interested fishers invest in the education and start-up costs needed to transition to this more sustainable gear.

It’s early on in this story, but the results are promising. And it’s one bright spot in an otherwise grim reality for wild salmon — and the orcas they sustain.

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