Keeping hope on the high Columbia | Outside

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SPOKANE — With thousands of miles of prime salmon habitat in the upper Columbia River, a restored chinook run there could dramatically increase the numbers of anadromous fish throughout the basin.

The tribes of the upper Columbia River — the Coeur d’Alene, Spokane, and Colville, as well as the First Nations of Canada — aim to do just that.

But it’s tricky. Daring even.

Consider that salmon and steelhead trout returning to the Snake River struggle largely because of the eight dams they must cross. These eight dams, four on the Columbia and four on the Snake, all have adult and juvenile fish passage facilities.

There is honest debate about their performance. Many scientists say every dam has an impact and eight is too many, hence their call to remove all four dams on the Snake River as a necessary measure to save wild salmon and rainbow trout of the Snake River.

But adult fish returning to the upper Columbia River will also have to cross eight dams before reaching Chief Joseph and Grand Coulee — two massive hydroelectric dams with no fish ladders. Juvenile fish must make their way through the turbines of the two large dams and over the spillways or through the turbines of the three small Avista Corp dams. on the Spokane River, all before passing eight more on the middle and lower Columbia River.

How is it possible? Or rather, is it possible?

The tribes think so and they are in the second phase of a four-phase project to figure out how to make it happen. They must do this without the power of the Endangered Species Act.

“We’re talking about getting the fish through five weirs that don’t have a fish pass. Sure, it’s a daunting task but, you know, that’s probably why it hasn’t been tried yet,” said Tom Biladeau, nonresident habitat restoration biologist for the fisheries program for the Coeur d’Alene tribe.

“If it was simple, someone would have done it. But the tribes are really committed to making this happen and there are many new or innovative technologies that were not available decades ago for getting the fish through the high head dams, and when I’m talking about getting the fish through, I’m talking about the juveniles going down and the adults going up.

The fish have disappeared from the territory of Coeur d’Alène for a century. But they used to spawn in places like Hangman Creek and other tributaries of the Spokane River. Spokane Falls, an impassable barrier on the Spokane River, was a destination for several tribes.

“Salmon and rainbow trout would hit there and, like Celilo and Kettle Falls, it would be a place where all the tribes would come to harvest fish,” said Aaron Penney, supplementation biologist for the Heart Tribe. of Alène.

At last summer’s Salmon and Orca Summit in Shelton, Wash., Coeur d’Alene Tribal Council member Hemene James issued a grave warning to the Nez Perces and other tribes of the northwest. of the Pacific who strive to preserve and improve salmon runs.

“My people are relegated to pulling fish out of the back of a truck,” James said. “Any of you with salmon should freak out. Excuse my language, you should shit in your pants because you don’t want to end up like us.

The disappearance of the Upper Columbia salmon began with the construction of the Little Falls Dam northwest of Spokane. Then came the Long Lake and Nine Mile Falls dams.

“They were the first that started to deplete salmon runs in the Spokane River,” Penney said. “And when Grand Coulee walked in, that was the nail in the coffin.”

He has spent his entire career helping salmon reclaim their territory. For about two decades, the Nez Perce man worked on his tribe’s efforts to supplement wild salmon and steelhead salmon with hatchery fish. He then ran the Nez Perce Tribal Hatchery. Now he leads a fledgling hatchery program for the Coeur d’Alene Tribe.

The Grand Coulee Dam is a high-head barrier with no passage for fish. The Chief Joseph Dam was built downstream. There is also no fish pass. Together, the two dams are the power-generating workhorses of the region.

The effort is therefore audacious. Undaunted, the tribes of the upper Columbia rise to the challenge. It begins with a long-running study that began in 2014 with Phase 1 – an effort by the tribes to assess the quality of habitat for salmon and rainbow trout in what is known as the area. blocked.

“The results of that, they were encouraging to say the least,” Biladeau said. “This modeling exercise estimated that tens of thousands of adults could be produced from the reintroduction into the blocked area. That is, tens of thousands of adult Chinook salmon, pushing out a hundred thousand We haven’t gone that far into the exercise of estimating how many adult rainbow trout might be produced, or coho, or lamprey, (but) it’s certainly on the horizon .

Phase 2 started last week. The fish reared by Penney were released into Hangman Creek, a tributary of the Spokane River, the Spokane River itself, and into Lake Roosevelt – the stretch of calm waters of the Columbia River behind Grand Coulee Dam.

These fish, about 5,000 in total, have been tagged so that biologists can track their movements downstream. Most had passive integrated transponder, or PIT, tags inserted into their abdominal cavities via a 12-gauge needle. But a small subset were surgically implanted with more sensitive acoustic tags.

PIT tags can only be detected a short distance from antennas or arrays, and detection efficiency varies from about 10% to 30%, said Toby Koch, a fish biology researcher at the US Geological Survey who participated in the study.

“Acoustic beacons, we can hear them from around 200 meters away on average and we usually have a detection probability greater than 95% on those.”

The downside, in addition to the surgery required to implant them, is that the acoustic tags flash after about 80 days. Signals from PIT beacons are only triggered when they pass over an antenna, so they last for years.

Together, the tags will show fisheries biologists how juvenile and possibly adult fish move through the blocked area, the part of the Columbia River upstream from Grand Coulee.

“Phase 2 is largely testing the feasibility of reintroduction,” Biladeau said. “Releasing fish, looking at survival, looking at passageways, looking at behavior and starting to fill those assumptions into this life cycle model so we can start making informed decisions going forward on the best course of action for reintroduction.

If the reintroduction is successful, ways will have to be found to get the juvenile fish through all these dams and the adults over or around them. New technologies such as the Whoosh system – a giant suction tube for adults – and floating surface collectors for juveniles placed in front of dams, show promise.

“A lot of opportunities”

There is evidence that reintroduction might be possible. The Spokane Tribes released 750 juvenile Summer Chinook to Chamokane Creek in 2017.

“They had to go through Little Falls Dam or through Little Falls (Dam). They had to go into Lake Roosevelt, where there are all kinds of predators, and they had to cross Grand Coulee Dam – another dam with no passage for fish,” said Tim Peone, resident hatchery manager. of the Spokane tribe. “Then they had to cross another reservoir and another dam without any sort of passage.”

It was all about reaching the downstream side of Chief Joseph Dam and entering the “anadromous zone”, an area where salmon and rainbow trout can still reach. Ahead of them was Wells Dam, the first of eight where the fish could be detected.

“We’ve had over 90 individuals detected downstream,” said Conor Giorgi, anadromous fisheries manager for the Spokane Tribe.

Further downstream, 24 were detected at Bonneville Dam and four in the Columbia River estuary.

In the summer of 2019, one of these fish, an adult female who was now big and strong from feeding in the ocean, started swimming upstream again.

“We watched her as she went through each of the roadblocks,” Giorgi said.

Eventually, she entered the ladder of Chief Joseph’s Hatchery below Chief Joseph’s Dam.

A year later, three more adults from the same release of juveniles were detected in the Columbia River. At least one has been documented as having been harvested and it is likely that the others have been as well.

Giorgi said the 750 juveniles released had a smolt-to-adult return rate of about 0.4%. Not a great survival rate overall, but on par with the return rates of threatened rainbow trout from the upper Columbia that year.

“Without any upgrades to the fish passage systems, nothing, just an impromptu release we did, we got a lot of hope out of it,” Giorgi said. “So we see a lot of opportunity, a lot of hope for this reintroduction effort. Yes, it is disappointing that we did not recover these three fish but, at the same time, it also expresses the benefits of the reintroduction. That we can have that cultural connection while contributing to fisheries downstream where other people also benefit is much larger than the Upper Columbia region alone.

A subsequent release of 1,400 Chinook smolts by the Coeur d’Alene Tribe showed that approximately 90 of these fish survived the passage downstream of the three Spokane River dams, as well as Grand Coulee, Chief Joseph and the Eight middle and lower Columbia River dams.

Phase 2 will be repeated and expanded to include adult monitoring in future years, all with the goal of learning what can be done to help the fish.

Giorgi said the tribes believe they can achieve this and do so without the benefits of the Endangered Species Act.

“We don’t tell anyone they have to. We’re not asking for operational changes, we’re not asking for increased abstraction, more discharges, reduced irrigation water power, anything. You maintain all of these current operations and benefits and see what we can achieve for salmon while continuing to provide these services, and at the moment the outlook is optimistic.

“My people are relegated to pulling fish out of the back of a truck. Any of you with salmon should freak out. Excuse my language, you should shit in your pants because you don’t want to end up like us.

Coeur d’Alene Tribal Council member Hemene James speaking at a summit with the Nez Perce and other Pacific Northwest tribes

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