South Fork Boise River

Category: Tributaries

  • eDNA results: Where are the fish?

    eDNA shows reduction in tributary habitat

    Back in June 2023 we worked with the Boise National Forest to grab some eDNA samples of tributaries to the SF Boise River. This work was adjacent to ongoing bull trout eDNA sampling efforts and for our purposes we were interested in understanding if there are detections of salmonid use of the tributaries. Salmonids include bull trout and other species like rainbow trout.

    Results took some time process. The Forest Service sent the samples to its lab in Missoula and the information did not come back for nearly a year. Then it took time to find a way to plot the information on a map.

    The information shows in some tributaries there appears to be a reduction of trout use of some of the small tributaries. If the trout were present, and if they shed enough eDNA into the water column, and if the sampling effort works, we should get a signal. Assuming the samples were accurate here is a capsule set of results:

    • Pierce Creek samples show trout present at the bridge where the passage reconnection project was implemented in 2011 (a bridge replaced culvert). But further upstream in the mainstem of Pierce Creek and its West Fork the samples were negative. Since the 2013 and 2014 debris flow events there is a waterfall that might be impassible for trout to access the upper reaches. Past fish sampling efforts had shown fish using the upstream reaches. This appears to be a reduction in available habitat.
    • Granite Creek sampling shows fish presence upstream of the culvert AND upstream of a water fall that appeared to be a problem for passage. But a kilometer upstream the samples were negative for trout eDNA presence. The positive sample however is encouraging. The culvert could present passage challenges at certain flows given its length.
    • Rough Creek tested positive downstream of the culvert for fish using the small stream. Samples one and two kilometers upstream were both negative. A large waterfall is present between the two negative samples. The culvert under the SF Boise River Road is perched and not very surprising the negative sample is a result.
    • Cow Creek shows eDNA presence near its confluence with the SF Boise River but negative one kilometer upstream. This is consistent with field observations from recent years.

  • Photos from December 2023 SF Boise Visit

    River and watershed conditions, such as risk of soil erosion, become most apparent in the winter when the growing season is over and vegetation growth does not obscure ground conditions. A field trip to the South Fork Boise River shows a number of the sites where some erosion control could be implemented.

    This stack of photos is in a .pdf format and is a huge 200 MB file and can be accessed here. It will open in a new tab.

  • eDNA Sampling

    June 7 we cooperated with the Boise National Forest to collect eDNA samples to help understand the presence and extent of salmonid fishes along some of the small tributaries to the South Fork Boise River. The sampling effort is led by field biologists with the Boise NF with some TU volunteers helping.

    Water in a tributary stream such as Pierce Creek, is pumped through a filter, and the filter is sent to a laboratory in Missoula, MT for analysis.

    At Pierce Creek (under the bridge) eDNA pumping equipment.

    The small tributaries to the South Fork Boise River can be an important contributor to the SF Boise fishery where trout can spawn in these small streams and add to the population of the next generation. While individually each tributary is a small water body, collectively the contribution provide a component that promotes resilience for the fishery since not all spawning can rely on the main river where we have seen impacts to habitat in recent years from landslides and constrained flows in low water years.

    Rough Creek sampling with equipment in the foreground of this picture.

     

  • Dispatches from Pierce Creek

    The March 30 planting project is done.  Here’s a round up of photos and observations.

    The Forest Service assigned five personnel. They provided instruction, equipment and leadership on the ground. They praised us saying we knew how to through a good party. They may be able to partner with new projects this season and promised to keep me in their loop. Barber Flats interestingly is a target.

    With last minute unanticipated subtractions and additions TU contributed at least a dozen and a half to two dozen persons including the cooking crew. Weather was perfect. Kudos to Fred Hebert and his two buddies for a chili based lunch with our kitchen equipment. They gave Leadership credits to one Eagle Scout.

    Boy Scouts (BSA) will monitor “take” during the summer. FS will share details with us.

    The BSA swelled our ranks immensely with scouts and their family members. There were easily four dozen persons all actively cutting and planting from 11:00 a.m. to 3:00 p.m. sans 45 minutes for lunch. Together we all placed literally hundreds of 12 to 18 inch pieces into the embankments along Pierce Creek both below and well above the bridge and even under the bridge and around wattles FS had installed earlier to bank retard erosion near the bridge. Rain is anticipated now soon to follow this week that should help.

    I would like to add to Dr O’s report the planting went really well and Doug did show and there were probably several other members that showed also who didn’t send in emails but may have been on some of the other lists.  Every one got fed well and there was no food left to clean up Fred was able to get a few of the scout to take seconds to polish off the chili.

    The Forest Service did an outstanding job in mitigating the impacts  of the migration barriers left after the initial big blowout the willows initially planted were well established below the bridge.  There is a potential barrier where the creek drops off the alluvial fan into the South Fork that will probably change after high water this year.  If BOR doesn’t start releasing water very soon we will probably seem some very high water on the SF later this spring.

    I did stop below the tailwater put in to see what the talk was on the so called alternate put in was about.  I don’t think it is a big deal yet.  It is a very steep high bank and only soft boats can be launched there You have got to want to fish that section pretty bad to put a boat down that bank.  At the 600cfs that the river was at there was a route thru the rapid.  There was at least one must make move a weaker boatman would probably not want to run it at this level or lower, once the river comes up it should open up and be plenty of room just some big waves and maybe a hole to stay out of.

    Over all it was a good outing couldn’t beat the weather

  • March 30: Pierce Creek Riparian Planting

    A final step in restoring Pierce Creek will happen on March 30, 2019 and we need volunteers to make it reality. Planting the streamside area around the rebuilt bridge at Pierce Creek (on the South Fork of the Boise River, near the Danskin boat ramp) will stabilize the stream bank of this important habitat.

    The Pierce Creek Bridge was installed in 2011 and the footings were then rebuilt in 2018 after watershed debris flows undermined the foundation. This project was inspired and led by Trout Unlimited, working with the Mountain Home Highway District and the Boise National Forest. With a bridge replacing a culvert on Pierce Creek, the free passage of wild trout and other fish species is secured for this tributary to the South Fork Boise River.

    Join the contingent of volunteers to help finish the job at Pierce Creek.

    The particulars:

    • Saturday, March 30, 2019.
    • Meet at the Albertson’s parking lot at Federal Way and Gowen Road between 8:30 a.m. & 9:00 a.m. We will make carpool arrangements and leave from there at 9:00 a.m. and carpool to the South Fork Boise River.
    • In the morning we will gather willow cuttings at locations along the South Fork Boise River.
    • In the afternoon we will plant the cuttings in the bank along Pierce Creek.
    • Lunch will be provided by Ted Trueblood Chapter of Trout Unlimited, using our eager and experienced cooking crew and equipment from our summer Trout Camp.
    • Total work time is estimated to be four to six hours. Mid-afternoon return to Albertson’s in Boise.
    • Bring work gloves.  Bring a folding chair if you have one for sitting at lunch.
    • Please RSVP to Bruce Johnstone at [email protected] by Thursday March 28.