Spring Chinook Salmon Fishing Update

springchinooke051223

From IDFG’s Joe DuPont:

Hi everybody.

It is time for my weekly spring Chinook Salmon update (May 21, 2024). So, let’s get right to it.

RUN UPDATE

The return of Idaho’s spring Chinook Salmon over Bonneville Dam is winding down. As of May 20, 2024, the return of these fish is around 95% complete. If you look at the red line on the figure below, you will see that fish passage is tapering off, and it looks like by the time we reach May 31, this run will be similar to what occurred in 2018 (about 88,000 adult fish).

Cumulative chinook counts at Bonneville 5-21-24

Now, let’s look at the harvest share table below to get a feel for where the fish passing over Bonneville Dam are going. This table has been updated so it now captures data through 5/20/24. Harvest shares have not changed much from last week which is what we would expect as we near the end of the return. Since last week, the Clearwater River return’s projected harvest share has gone up slightly to 4,680 adult fish (darker peach row). The Rapid River return’s projected harvest share has gone down slightly to 1,909 adult fish (darker blue row). Finally, Hells Canyon’s projected harvest share has also gone down slightly to 701 adult fish (green row). In two to three weeks, we will likely switch over to using PIT tag detections at Lower Granite Dam to calculate the final harvest shares for these three fisheries. Additionally, we will utilize genetic data collected at Lower Granite Dam to refine the harvest share for the Rapid River return. At times, this data has resulted in the harvest share increasing significantly. We will likely have the results of this analysis for you during the first week of June.

Estimated spring Chinook harvest shares based on Bonneville PIT tags 5-21-24

In my past updates, I have shared data with you collected at Bonneville Dam. However, we now have enough meaningful information from Lower Granite Dam that I decided to put together the figure below for you. This figure summarizes the daily PIT tag expanded estimates at Lower Granite Dam for fish destined for the Clearwater and Rapid River run fisheries. Notice how since May 15, daily counts of fish destined for the Clearwater have been at 900 or more. These are notable numbers of fish and should provide good fishing as they migrate upriver. These fish should start reaching the North Fork Clearwater River later this week. Often, when flows exceed 30,000 cfs in the Clearwater River, fish will stack up in the Big Eddy hole. However, flows have been below 30,000 cfs for the past three days and should remain there for at least two more. This should make it easier for fish to navigate through this hole and continue their migration upstream. Since May 14, daily counts of fish destined for Rapid River have been in excess of 500. It typically takes 7-10 days for these fish to migrate from Lower Granite Dam to the fishery in the lower Salmon River. Flows have been below 40,000 cfs for three days now and should remain that way into the foreseeable forecast. This means these fish should be able to navigate the Slide Rapid and move into the fishery this week.

Daily Chinook Salmon counts at Lower Granite Dam based on PIT tags 5-21-24

 

FISHERIES

Clearwater River Basin Fishery

Now that harvest has picked up in the Clearwater River basin, in future updates, I will be including the table below that shows how many fish we estimate were harvested each week and where they were harvested from. Additionally, you should pay attention to the blue portion of the table below. This shows what our harvest distribution goals are for different river sections and how many fish remain before that goal is met. When you see a river section getting close to its harvest distribution goal, a closure may occur shortly to help ensure harvest opportunities are distributed fairly across the basin. As you can see in the table below, last week (interval 4) harvest picked up significantly. We estimate that 334 fish were harvested with most of that harvest occurring in river Section 1 (downstream of Cherrylane Bridge). Catch rates were OK in Sections 1 and 2 at 18 hrs/fish, but still slow in the North Fork (Section 3). I expect catch rates will improve this week as more fish move into the fishery. We are supposed to get some rain tonight and tomorrow which will bring flows up later this week. This could improve fishing as long as the river doesn’t get too brown.

Number of chinook harvest weekly in the Clearwater basin 5-21-24

One interesting new technology we have is now that some people are electronically tagging their fish on their phone, I can look at this information when it is uploaded. Based on this information, I can tell you that more people have e-tagged fish in the Clearwater River today than any other day of the year. Interestingly, it appears there wasn’t much of an early morning bite today as the earliest fish was e-tagged at 7:48 am. After that, it appears it got hot! It just goes to show you, don’t give up if don’t catch them right away.

Rapid River Run Fishery

We estimate that two fish were harvested last week in the Rapid River Run fishery – one from Section 3 in the lower Salmon River (Time Zone Bridge to Shorts Creek) and one in the Little Salmon River. I suspect the reason we didn’t observe any fish being harvested in sections 1 or 2 of the lower Salmon River (downstream of Time Zone Bridge) is because the river turned brown on Friday and was full of debris. River conditions are good right now, so I expect sections 1 and 2 of the lower Salmon River to provide good fishing this week after it opens on Thursday.

Hells Canyon Fishery

For the second week in a row, the best catch rates were observed in the Hells Canyon fishery just downstream of the dam (14 hrs/fish). We estimated that 75 adults and 8 jacks were harvested last week. Fishing should continue to improve below the dam as trapping will not occur for at least one more week.

Number of chinook harvest weekly in hells canyon 5-21-24

That is all I have for you today.  Good luck fishing!