3 days ago
Low flow blues: springer fishing made tougher by below-average flows on Clearwater River
Jun. 1—By the time you are reading this, the spring chinook fishery on the lower end of the Clearwater River may be fading.
It is the first day of June and the tail of the run should start to get thinner and thinner as biology urges the fish upriver and closer to their spawning grounds — be it hatcheries or natal streams. At the same time, fishing should pick up closer to the hatcheries and acclimation sites where the fish were released as juveniles.
Late last week, Joe DuPont, regional fisheries manager for the Idaho Department of Fish and Game at Lewiston, speculated that about 75% of the adult chinook bound for the Clearwater River had already passed Lower Granite Dam. At the time, he was hopeful that a bump in flows related to warmer weather would deliver a corresponding bump in catch rates during what has been a tough season for many anglers on the lower Clearwater.
Despite the best run since 2016 that has produced an estimated harvest share of more than 4,800 adult chinook, anglers had caught only about 800 adult chinook as of the last update. There is much speculation about what is causing the low catch rates but the leading theory behind them and the one DuPont adheres to is that fishing is more difficult when river flows, measured in cubic feet per second, are low.
"I would say once flows drop below the upper 20-thousands, we see catch rates drop in the pass-through fisheries," he said. "It's very evident, when flows go down, catch rates go down."
Higher flows will push chinook to the edges of the river. But DuPont said his experience, which spans four decades starting as a guide in Alaska to his job now, tells him chinook prefer deeper water far from shorelines.
"Something is ingrained in them. It has to be a safety type thing. It comes with the depth and probably staying away from the shoreline.
The low flow theory shows up, he said, at places like Big Eddy where fishing can be hot during high flows when fish confused by the strong and swirling current stall and stack up. But during low flows, they plow through and fishing quality drops.
It shows up at the Hog Line — the string of boats across the Clearwater just above the Railroad Bridge at Lewiston.
Daily headlines, straight to your inboxRead it online first and stay up-to-date, delivered daily at 7 AM
"When flows drop, the center boats are the ones catching," he said.
The Clearwater River was forecast to flow at a rate of about 30,000 to 34,000 through Monday before starting a steep slide. The next run update, expected early this week, will show whether the higher flows did indeed help anglers.
DuPont said the Nez Perce Tribe has reported that its gillnet fishers are also having a tough season. As of last week, about 240 chinook had been caught in gillnets.
Even if fishing is tough here, the strength of the run should lead to better angling farther up the Clearwater where chinook concentrate at places like the North Fork of the Clearwater River and the area in front of Clear Creek. Fish stack up at both spots as they seek to return to the hatcheries from which they were released as juveniles. Likewise, the South Fork of the Clearwater, which is much smaller than the main Clearwater, should give anglers a better shot even if chinook travel up the middle instead of along the edges.
Rapid River
On the Salmon River, the estimated harvest share jumped last week following genetic analysis of fish trapped at Lower Granite Dam, which showed a better-than-projected return to Rapid River that fuels fisheries on the lower Salmon and Little Salmon rivers.
The harvest share had been pinned at about 800 but is now estimated to be about 1,200.
Lower Snake
The Washington Department of Fish and Wildlife will allow four more days of fishing on the lower Snake River. The fishery at Little Goose Dam will be open Tuesday and Friday and the Ice Harbor fishery will be open Wednesday and Thursday. The days were added when the return of hatchery spring chinook to the Snake River and its tributaries was upgraded.
Barker may be contacted at ebarker@
