South Fork Salmon River Update - June 27, 2023

Hi Everyone.

After the first four days of fishing on the South Fork Salmon River for 2023, I wanted to provide you all with an update on how things are progressing down there. 

Harvest Share Update

I’ve got some good news on our estimated harvest share for the 2023 South Fork Salmon fishery - It has increased a few hundred fish since my update last week. We’re still well below the pre-season forecast, but the current estimated harvest share based on the number of hatchery adults over Lower Granite Dam, is 912 (see table below).

The increase in harvest share is because most hatchery adults bound for the South Fork Salmon have made it over Lower Granite Dam now, and they have surprised us by making it through the hydrosystem at a much higher rate than they typically do. On average over the past five years, we’ve typically only seen about 69% of South Fork bound adults over Bonneville Dam make it over Lower Granite Dam (conversion rate). However, this year we’ve seen 93% of those fish make it through so far. This was mainly influenced by a closure on the mainstem Columbia River in Oregon and Washington in early June due to wild fish impact exceedance in that fishery. During that time Idaho-bound fish were not harvested in the mainstem Columbia, and more of them are going to make it to Idaho fisheries this summer! (see 2023 conversion rates relative to the 5-year averages below)

Run Timing

Fish have arrived on the South Fork Salmon. The graph below shows the number of PIT tags detected at the South Fork Guard Station (SFG) antenna as well as the Krassel (KRS) antenna since June 15th. There have been a steady number of detections each day on both antennas, but it really picked up on the SFG antenna over the past two days. You can expect those fish to be entering the fishery area this week, as it typically takes about 3 days for those fish to reach the KRS antenna (just below the fishery). Interestingly, there were no PIT tags detected at the KRS antenna yesterday. However, that is going to pick up as those fish crossing SFG over the past few days make their way up river. 

A word of caution on expanding PIT tags: Not all of the McCall PIT tags expand to represent 50 fish as I mentioned in a previous update. The ‘run-at-large’ PIT tags are the only ones that expand at that rate and represent less than half of all tags released from McCall Hatchery each year. Of the PIT tags released each year in adipose-clipped fish from McCall Hatchery, only 70% of that release group represents the ‘run-at-large’ and are expandable. The other 30% of the release group is handled differently during their juvenile outmigration through the hydrosystem and therefore do not represent the untagged population.  Additionally, many of the tags I used to construct the figure above were placed in returning adults at Lower Granite Dam this spring. Now that tags are coming into the South Fork from multiple sources, I would encourage you not to focus on trying to expand tags to a number of fish at the SFG and KRS antennas, but rather use detections at those antennas simply to indicate when the fish are arriving. 

Harvest Estimates

There was a decent amount of fishing effort on the South Fork during the first four days of the fishery (Thursday through Sunday). In total, we estimated over 4,000 hours of fishing effort between the four days. Since it is still pretty early in the run, fishing was relatively slow (36 hours per fish caught). We documented some harvest this weekend though, and I got to see some friends hook into fish myself (although I didn’t hook one myself). 

Our total harvest estimate for the first four days of the fishery is 94 hatchery adults kept (see table below). The breakdown was approximately 16 harvested on Thursday, 23 harvested on Friday, 31 harvested Saturday, and 24 harvested Sunday. We physically handled 42 harvested hatchery adults at our check station over the weekend. 

Hatchery Returns

So far, the weir has only trapped two adult Salmon this season. They are eagerly awaiting a big push of fish in the next week or so. Stay tuned. 

Fishery Outlook

With a current harvest share of 912 hatchery adults in the South Fork Salmon, and an estimated total harvest so far of 94 hatchery adults, we still have a little over 800 adults remaining in our harvest share. I’m planning to have our data from this week (Monday through Thursday) worked up by Friday of this week so we can have a better idea of where we’re sitting going into the holiday weekend. Expect another update from me in the early afternoon on Friday, June 30. I'm certain the fishery will at least run through Sunday, July 2nd, but I'll let you know on Friday whether you can expect the fishery to run through Tuesday the 4th or not. Keep in mind that there will be a lot of effort over the weekend, and if the fish show up we could see a lot of fish get harvested. We have seen upwards of 150 fish harvested per day in past years over the 4th of July holiday weekend.

That’s all for now. Have a great week everyone!