Older steelhead making up bulk of return

There’s a good news-bad news scenario shaping up in this year’s return of steelhead to the Salmon and Snake rivers.

The bad: One-ocean steelhead aren’t showing up as projected.

The good: Two-ocean fish are bailing us out.

We are talking about the A-run here — steelhead that return mostly to the Snake, Salmon and Grande Ronde rivers. Most of them spend just one year in the ocean before returning as adults, But a small fraction stay at sea for two to three years.

As far as timing, the older fish tend to lead the charge and are followed by the youngsters. That profile has shaped up this year. The front end was loaded with two-ocean and three-ocean fish, so much so that early returns spiked above the 10-year average. But with the meager showing from one-ocean fish, the run now trails the 10-year trend.

Joe DuPont, regional fisheries manager for the Idaho Department of Fish and Game, said 90% of the run, as measured at Bonneville Dam on the Columbia River, has been composed of two-ocean fish. The Grande Ronde run is made up of about 83% two-ocean fish.

“Usually it’s kind of the other way around,” said DuPont. “So we are missing a huge portion of that run. Hopefully it means those fish decided to stay out in the ocean another year.”

Last year, scientists from NOAA Fisheries recorded the second-best ocean conditions in a 24-year data set. That should be good news for anadromous fish, and both spring chinook and sockeye returns exceeded expectations.

But steelhead behave a little differently. When they reach the ocean as juveniles, steelhead tend to head out to the open ocean. Chinook, sockeye and coho tend to stick closer to shore. Scientists have a long data set of near-shore ocean conditions but know little about conditions farther out or exactly where steelhead go.

DuPont said the two-ocean component of the A-run is higher than average and higher than fisheries managers would have expected based on last year’s return of one-salt fish.

“We could potentially see more two- and three-ocean fish come over Bonneville than we have since 2010 or 2011,” he said. “I would say they are bailing us out.”

The bigger B-run steelhead that tend to spend two years in salt water are just starting to show up at Bonneville Dam. Those fish are mostly bound for the Clearwater Basin and the Middle Fork of the Salmon River. It’s super early, with just 5% of the run above the dam, but DuPont said the numbers are promising.

“The numbers we are seeing are great. We haven’t seen this many fish since 2011,” he said. “Granted, it’s still very early but it’s an exciting start.”

Barker may be contacted at ebarker@lmtribune.com or at (208) 848-2273. Follow him on Twitter @ezebarker.

Season opens Thursday

The catch-and-keep season for steelhead opens Thursday on the Snake, Salmon and Grande Ronde rivers, below Memorial Bridge on the Clearwater River and on the North Fork of the Clearwater River.

Under a new scenario this year, the rest of the Clearwater River and its South Fork will open for catch-and-keep steelhead fishing Sept. 10. Those sections will revert to catch-and-release fishing from Oct. 15 to Nov. 9. The catch-and-keep season returns Nov. 10 and runs through the end of the year and into the spring.

By the numbers

The fall chinook run is on pace to meet and perhaps surpass expectations of fisheries managers.

The fishing season on the Snake River in Washington and Idaho opened last week. The Idaho Department of Fish and Game recorded the harvest of about 180 adult chinook and Washingon tallied the harvest of another 90 fish.

Fisheries managers are forecasting a bit less than 26,500 adult fall chinook to return at least as far as Lower Granite Dam. Some of those will be trapped at the dam and kept for spawning at various hatcheries.

Thus far the return is on pace to meet the forecast, said Becky Johnson, production director of the Nez Perce Tribe’s Department of Fisheries Resources Management. The fish are a little ahead of schedule, which makes it difficult to determine if the run is just early or more numerous than expected.

“There is a chance the run will be above (the preseason forecast). It’s kind of early to put a stake in the sand but it looks good,” she said.