Idaho Species Series: B-Run Steelhead

In Part I of IWF’s Idaho Species Series: B-Run Steelhead, we focused on the history of Idaho’s iconic oversized B-run bruisers. The series will continue with conversation about what we can do to conserve these stocks, including conversations with guides and anglers whose lives were changed forever by them. With the legend and lore surrounding Idaho’s B-run steelhead, it is important that all Idaho anglers understand the nitty-gritty details regarding the status of Idaho’s most iconic fish.

Management

Marika Dobos is the Anadromous Fisheries Staff Biologist at the Idaho Department of Fish and Game. She works collaboratively on wild salmon and steelhead monitoring and evaluation for statewide programs and oversees all projects within the Clearwater Region, specifically. 

She explained that the majority of funding for IDFG’s statewide wild salmon and steelhead program comes from Bonneville Power Administration contractually required mitigation requirements largely due to the lower Snake River dams impact on now Endangered Species Listed species like salmon and steelhead.

IDFG has an obligation to perform status assessments for listed species. They monitor populations, identify trends and evaluate things like restoration actions in select watershed areas. That is all wrapped up in the state’s status assessment which determines alignment with the NOAA Fisheries Recovery Plan for Snake River Spring/Summer Chinook Salmon and Snake River Basin Steelhead

Currently, Idaho’s steelhead are managed under the 2019-2024 Fisheries Management Plan. Next year, IDFG will begin formulating the next statewide management plan, to include public comment and data from recent wild salmon and steelhead returns.

Courtesy of Idaho Fish and Game

Trends

Dobos noted that steelhead in Idaho are managed by what’s called a major population group. In Idaho, we have two major population groups, the Clearwater and the Salmon. This is important because ESA listing and delisting is based on major population group recovery, as opposed to single populations, OR entire species.

Last year, Dobos recognized Idaho saw an increased proportion of two ocean, B-index fish. 

“It’s really hard to predict steelhead returns, Dobos said. “We have these predicted runs, but what actually comes back can be off by quite a bit. Last year was the case where more two-ocean fish returned, categorized as B-Index fish, than expected. In comparison, there were far fewer than one-ocean, largely A-index fish. The unfortunate part about that is when we don’t see one-ocean fish show up, it could mean they stayed in the ocean and will return as two ocean fish, but, more often, that isn’t the case. Usually it means they did not survive.” 

Courtesy of NOAA

What To Expect in 2023

“If sea surface temperatures are warm, that’s not a good thing. It's pretty indicative that the open ocean is in bad shape and that’s not good for steelhead,” Dobos continued. 

Earlier in March, NOAA released its 2023-2024 forecast for Columbia River and Snake River basin salmon and steelhead. The Snake River summer steelhead, which includes Idaho’s famed B-run, is forecast to have the lowest return in history. 

Only 910 wild B-run steelhead are forecasted to pass over Lower Granite dam in the 2023-2024 season.

The 9,560 total wild steelhead (A-run and B-run combined) forecasted returning to Idaho is only 13-percent of the NOAA’s designated escapement goal of 72,000 wild steelhead from Idaho’s component of the Snake River basin goals. 

Courtesy of IDFG

Courtesy of NOAA

“Since the last relatively sizable run in 2015, returns have really decreased and it’s changed a lot in our state in a lot of ways,” Dobos continued. “It’s made a lot of our monitoring efforts more important because our information becomes that much more valuable when these numbers are coming back. It affects how we’re managing the fish, how all sorts of organizations, not just managers, relate to these fish.” 

“Most of the power we have is the information we can get out,” Dobos said. “Idaho has a lot of information on our steelhead, a lot more than a lot of places.”  

Courtesy of NOAA

More About Classification

Courtesy of Idaho Fish & Game: 

“The terms A and B are unique to steelhead management in the Columbia and Snake river basins and does not classify specific populations.

Rather the A and B terms define steelhead based on their adult size and the date they pass Bonneville Dam during their adult migration upstream. Snake River basin steelhead populations can be broadly termed “A-run” or “B-run” based on the dominant traits expressed. It is important to note that steelhead are extremely diverse, so there are overlaps in migration timing, age, and size across all summer-run steelhead populations in the Columbia River basin. To understand the reasoning for defining these two “types” of steelhead, we need to go downriver into the mainstem Columbia River and look at some history.

Dworshak National Fish Hatchery was completed in 1969 during the construction of Dworshak Dam and used wild fish returning to the North Fork Clearwater River as broodstock to ensure that those large steelhead would continue returning at similar levels as the wild population that would be extirpated. Because the wild North Fork Clearwater River steelhead were much bigger than steelhead from other Columbia River hatchery programs, they were first termed “B” steelhead.

The term “A” steelhead went to all other hatchery steelhead stocks. Meanwhile, steelhead bound for Idaho were drastically declining, and in 1974, Idaho closed steelhead fisheries for the first time ever to protect Dworshak Hatchery broodstock and wild populations. To further protect these unique Idaho wild and hatchery fish, Columbia River harvest in the 1970’s and 1980’s was initially managed using a date method at Bonneville Dam because of the historic distinction in run timing. Group A steelhead were defined as wild- or hatchery-origin steelhead passing Bonneville Dam between July 1 and August 25 and Group B steelhead were those wild- and hatchery-origin fish passing Bonneville Dam between August 26 and October 31. Bonneville Dam escapement goals were developed for wild summer-run Group A and Group B steelhead so that a certain amount of wild fish would be expected to pass Lower Granite Dam.”