Spring Chinook Salmon Fishery Update (7/16/2024): Clearwater River Return, Rapid River Run, and Hells Canyon Fisheries

Hi everybody.

This will be my last weekly spring Chinook Salmon update for the season.  As a heads up, the North Fork Clearwater River has now been closed to all salmon fishing. We expect minimal effort and harvest in those fisheries that remain open. For that reason, those fisheries currently open will likely remain open until the end of the season – August 10, 2024. We will send out a notice if any other closures occur before then.

Because this is my last spring Chinook Salmon update of the season, I am sticking to my tradition by providing a rough forecast for next year’s return. You can view this forecast at the end of this update.

HARVEST SHARES

Harvest shares for the different Chinook Salmon fisheries in the Clearwater Region are shown in the table below. Harvest shares as of July 16, 2024 are 4,755 adult fish for the Clearwater River Return fishery (darker peach row), 2,449 for the Rapid River Return fishery (darker blue row), 822 for the Hells Canyon fishery (green row), and 244 for the Lochsa Summer Run fishery.

FISHERIES

Clearwater River Basin Fishery

The only place we observed people fishing for spring Chinook Salmon in the Clearwater River basin last week was in the North Fork Clearwater River (River Section 3). We estimate that 52 adults were harvested last week with catch rates being excellent at 5 hrs/fish (see table below). That brings the total harvest in Clearwater River basin for the season to 4,308 which leaves 447 more fish to go before our harvest share is met. A total of 974 fish have been harvested in the North Fork Clearwater River which is right at the harvest distribution goal we are trying to achieve (20% of the harvest share). That brings us to a dilemma, we have harvest share remaining that could be caught in the North Fork Clearwater River, but we are also concerned about collecting enough broodstock to meet the full production goals for the entire basin. Right now, we are currently about 1,800 fish short of meeting our full production broodstock goals for the entire Clearwater basin. Broodstock collection at Dworshak Hatchery will be critical if we are going to meet this goal. On paper there are still enough fish still in the system to reach the full production goal, but there is no certainty until the fish swim into the hatchery trap. So, we have decided to error on the safe side and shut down the North Fork Clearwater fishery effective immediately (July 16, 2024). All other river sections currently open will remain open until August 10 unless notified otherwise.

Lochsa River Summer Run Fishery

We observed very few people fishing for summer Chinook Salmon on the Lochsa River last week. Based on the people we interviewed, only two adults were harvested and catch rates were slow (36 hrs/fish). We are well short of our harvest share, and as such, this fishery will remain open until August 10 unless otherwise notified.

Rapid River Run Fishery

We observed just one person fishing the Little Salmon River all of last week, and that person caught one jack. Humorously, when we interviewed that person he had only fished for half an hour which means catch rates for the week were 0.5 fish/hr – potentially the best we have ever seen for a week period. We are still about 500 fish short of our harvest share. As such, the Little Salmon River will remain open for at least another week.

Hells Canyon Fishery

Fishing effort and catch rates finally dropped off in the Hells Canyon Fishery. I suspect the intense heat had something to do with it. All last week we estimate that only 2 adults were harvested and catch rates were 36 hrs/fish (see table below). That brings the total harvest for the season to 788 adults and leaves 36 more before we reach our harvest share. Because we don’t anticipate much harvest for the remainder of the season, this fishery will remain open until August 10 unless otherwise notified.

2025 FORECAST

As I indicated earlier, one of my traditions for my last Weekly Chinook Salmon update is to provide a rough forecast for next year’s spring Chinook Salmon returns based on the number of jacks we saw this year. You need to be aware that the method I am using is based on PIT tag run estimates at Bonneville Dam which are not as accurate as the “official” forecasts we will put out at the end of the year that utilize genetic data collected from fish trapped at Lower Granite Dam.

The principle behind these forecasts is there is a relationship between the number of jacks that return one year to the number of adults that will return the following year. The more jacks that return, the more adults we can expect to return the following year. The two figures below show the number of adults (yellow bars) and jacks (red bars) that have passed over Bonneville Dam (based on PIT tags) that are destined for the Clearwater basin and Rapid River since 2009. If you look at these graphs, you will notice that in the years we had large jack returns, the following year the adult return tended to be big. On the other hand, when the jack return was small, we tended to see small adult returns the following year.

I created the table below that matches up one year’s jack return with the following year’s adult return so you can better view this jack to adult relationship. As you can see, there is a lot of variability in this relationship, but there is some correlation (over 60%). At the bottom of this table, you will see the cells in yellow. These are next year’s forecasted adult returns for the Clearwater River basin and Rapid River based on the average relation between jack and adult returns. The Clearwater’s adult return is forecasted to be about 15,000 adult fish which about 4,000 fish less then returned this year. However, we actually had more jacks return this year than last year. Let’s hope next year’s return comes in higher than forecasted like occurred this year. For the Rapid River return, the forecast for next year is 12,148 adults which is better than what occurred this year (8,199). However, fewer jacks returned this year than last year. This year, the Rapid River return came in under forecast. Let’s hope that doesn’t happen again next year. As a reminder, these are just forecasts, and there can be a lot of error around them. However, these forecasts suggest that next year we should be able to provide some decent fishing opportunities for spring Chinook Salmon.

Well, that is it for my spring/summer Chinook Salmon updates. With the fall Chinook Salmon season starting on August 18, and the steelhead catch-and-release season already open, stay tuned for some updates in the near future on these fisheries.

I hope you are all enjoying your summer.