Spring Chinook Salmon Fishing Update 5/8/2024: Rapid River Run, Hells Canyon, and Clearwater River Fisheries

Hi everybody.

I’m back from the conference I was at, so let’s get right to my weekly spring Chinook Salmon update (May 8, 2024).

Run Update

Since my last update on 4/20/2024, fish counts at Bonneville Dam picked up considerably, peaked on May 3 at almost 6,000 adult fish, and then have dropped off (see figure below). We need these counts to pick back up or at least stabilize for a few more days for us to achieve or exceed our preseason forecast. The tangle net test fishery near the mouth of Columbia River has shown steady catch rates for the past two weeks which gives me hope this will occur. When you compare this year’s counts (red line) to the 10-year average (dotted black line), it may seem like this run is doing OK. However, don’t let the 10-year average fool you as there have been some poor salmon returns in the last 10 years. We want better than the 10-year average. 

One of my favorite ways to evaluate the Chinook Salmon return at Bonneville Dam is to look at the counts accumulated daily. The figure below does just that. Basically, what cumulative counts show is the total number of fish that have been counted up to a given date. The figure below ends on May 31, and that is because after May 31 the fish destined for Idaho’s spring Chinook Salmon fisheries will have almost all passed over Bonneville Dam. After May 31, almost all the fish passing over Bonneville Dam will be summer run fish. If you look at the figure below, you can see counts this year (red line) are better than the previous seven years, excluding 2022. However, if counts don’t pick up again, I suspect this year’s spring return will end up somewhere between what occurred last year last year (dotted black line) and 2018 (dashed grey line).

All right let’s look at what the PIT tag detections at Bonneville Dam tell us about how many of these fish are destined for Idaho and what we are projecting for harvest shares for each of Idaho's spring Chinook Salmon fisheries. I have updated the table I shared with you in my last update (see below), so it now captures data through 5/6/23. This table shows that the Clearwater River return’s harvest share is projected to be 3,789 adult fish (darker peach row) which is up from what I reported in my last update (2,612 fish). The Rapid River return fishery (darker blue row) is projected to have a harvest share of 1,854 which is down from my last update (2,487 fish). Finally, the Hells Canyon fishery (green row) is projected to have a harvest share of 684 fish which is also down from my last update (824 fish). It is important to realize these harvest shares assumed that the run has an average run timing (about 60% complete). However, if the actual run timing is later than average, then the harvest share will go up, and if the run timing is earlier than average our harvest share will drop.

I do what to bring to your attention that if the harvest shares listed above are fairly accurate, we may want to adjust the season for the Clearwater River return fishery. If you read my first update (Chinook update 4-25-24), you may recall that I presented “harvest matrixes” for each of the fisheries that describes the seasons and limits anglers want us to apply based on the harvest share. The harvest matrix for the Clearwater River return fishery suggests that if the harvest share is greater than 2,000 adult fish, anglers would prefer a 7-day/week fishery. Right now, we are projecting the Clearwater River Return fishery will have a harvest share of 3,789 fish. If this harvest share does not drop by next week, this information will be presented to the commission (on May 16) so they can discuss if this fishery should be expanded from a 4-days/week fishery to a 7-days/week (except for the North Fork). We will keep you informed on any decisions that are made.

Fisheries

Last week we observed the first harvested spring Chinook Salmon of the year. This fish was caught in the lower Clearwater River, and we estimate that a total of two fish were harvested. It looks like by this weekend daily counts of adult Chinook Salmon at Lower Granite Dam could start exceeding 500 fish which should improve fishing. However, it is difficult to project fish passage right now as counts at the dams downstream of Lower Granite are bouncing up and down due to changes in flows, changes in spill, a temporary power house outage, and changing fisheries. For those who like to fish the Salmon River, give it another week, and some of the fish passing over Lower Granite Dam should start reaching the lower end of the fishery.

Good luck fishing!