Surplus summer Chinook salmon that traveled more than 500 river miles up the Columbia River to Wells Hatchery have continued migration after being trucked upstream and released in several locations above Chief Joseph and Grand Coulee dams by the Confederated Tribes of the Colville Reservation over the past two years.
About 20 of the 392 released salmon have been detected in Canada. At least one went downstream past Chief Joseph Dam and ventured up the Okanogan River. Dozens more traveled back and forth multiple times through Rufus Woods Lake above Chief Joseph Dam.
Six of them spawned next to the dam, in a shallow gravel area that had not previously been identified as a possible spawning ground. One fish found its way to the Nespelem River to spawn. And three dozen of 100 fish that were released in the Sanpoil River spawned within 6 miles of their release site.
The Northwest Power and Conservation Council's Fish and Wildlife Committee got a thorough briefing on what the Colville Tribes Fish and Wildlife Department is learning from releases of PIT-tagged and acoustic-tagged Chinook that began in 2019.
"We're obviously very, very excited about this project and effort," Casey Baldwin, the tribe's senior research biologist, told the Council committee on Jan. 12.
Baldwin said the tribe is conducting cultural and educational releases on a parallel path to the phased approach for reintroducing salmon in the upper Columbia River being pursued through the Council's Fish and Wildlife Program.
By tracking the fish from these releases, the tribe will be better informed about how to conduct future studies, he said. "It's a lot easier to set up an experiment when we know a little about survival and behavior," he said.
In 2019, the Council received a Phase 1 report from the Upper Columbia United Tribes which found the technology is available for upstream and downstream passage at both Chief Joseph and Grand Coulee dams, and hundreds of miles of suitable spawning and rearing habitat above the dams is available. The Independent Scientific Advisory Board agreed with the assessment, and recommended additional analyses before moving on to the second phase.
Baldwin said the tribe has some objectives that aren't consistent with the timeframe of the Council's phased approach for reintroducing salmon above the dams. Those include having ceremonies and keeping the salmon culture alive, providing harvest opportunities in areas that have not had anadromous fish for between 60 and 110 years, and educating tribal members and others through activities, such as raising salmon in classrooms and releasing them.
"It's important to the tribe to do some of these additional releases to meet some of these objectives," he said.
The releases started in 2019 with three ceremonies at the Columbia River on the Colville Indian Reservation. Elders and young people participated in freeing 90 salmon, by forming a human chain from the salmon truck to the river, and passing a water-filled rubber "boot" holding an adult Chinook, which was released when it reached the river.
Colville Tribal Councilman Jarred-Michael Erickson, who chairs the council's natural resources committee, explained why it's important to him to move forward with releasing salmon in areas that haven't seen anadromous fish for almost a century.
He said his mother—who wasn't raised with tribal traditions—hadn't understood the emotions surrounding the loss of salmon until she attended one of the ceremonies. During the release, he said, she started crying while watching the reactions of elders as they reconnected with salmon. "It was really emotional for a lot of our people," he said.
Baldwin said in addition to the 90 fish released at those three ceremonies, tribal biologists released 59 salmon with acoustic tags and 93 salmon with PIT tags into Rufus Woods Lake for a tracking study.
From the 2019 releases, he said, 76 percent survived and remained in the reservoir into October's spawning season. Only two fish, or 3.4 percent, were detected below Chief Joseph Dam by mid-October, which is a very low initial fallback rate, he said. One of those fish made its way into the Okanogan River, he said. That fish's journey is an indication that falling back through the dam is not always lethal, he added. More fish were detected below the dam after spawning season in mid-October, he said, but those could have spawned and died, later drifting downstream past the dam.
At least three fish swam up the Nespelem River, and one spawned there.
Most of the fish made multiple trips upstream, and then back downstream to Chief Joseph Dam, he said, noting that on average, fish made five trips upstream, and two trips downstream. "What we found out is, some fish will do almost anything" to find a suitable spawning area, he added.
The vast majority—92 percent—were first observed upstream after release, he noted. So although they originated from a hatchery farther downstream, their instincts were to swim upstream to spawn, he said. Once they reached the area below Grand Coulee Dam, there was no way to detect them, so receivers near the dam would be useful for future studies, Baldwin said.
In 2020, there were no ceremonial releases due to the ban on gatherings because of the pandemic, he said. In late July, biologists released 50 fish with acoustic tags into Lake Roosevelt—25 just above Grand Coulee Dam, and 25 at Northport, just south of the Canadian border. He said initial reports suggest that about 20 fish were detected in Canada, and several were detected by Douglas County PUD downstream of Chief Joseph Dam. But with dozens of receivers in the 150-mile long reservoir above Grand Coulee, it will take a few more months to analyze the tens of thousands of detections throughout the lake, he said.
A couple weeks after those releases, another 100 Chinook were unexpectedly available for release, so an impromptu decision was made to release them in the Sanpoil River, just upstream from Grand Coulee Dam, Baldwin said.
After their release in August, a drone fly-over confirmed that many were holding in pools. By October, they started to spread out to spawn, he said.
Baldwin said three of the fish were detected upstream in the West Fork of the Sanpoil River, but with limited time and staff, biologists focused on the 5-mile stretch of river that encompassed the area above and below the two release sites, counting 36 redds from Oct. 8 to 22. "We found this to be a really good outcome—that they survived so well, and spawned apparently in a fashion you would expect wild fish to be spawning," he said.
Baldwin said biologists don't know if any of the Chinook spawned farther downstream, in the 35 miles of the Sanpoil River between the release sites and the mouth of the river. Three were detected at a downstream weir in late October, he said.
If spawning was successful, their offspring may be caught in a downstream rotary screw trap next spring, Baldwin said. Those fish will be tagged if they're big enough, and genetic sampling will be used to identify their parents.
He noted that all of the fish—which are not listed under the Endangered Species Act—were tested for disease, and genetic samples were taken from each so their offspring can later be identified.
Baldwin said that by using surplus summer Chinook from Wells Hatchery for these releases, the tribe is sacrificing fish they would otherwise receive to share with tribal members for food and for tribal ceremonies. "It's a tradeoff," he noted.