Three Rivers Trout Unlimited - July 2024 Newsletter
Written by Bill Gerdts and Natasha Kacoroski with contributions from Alix Lee-Tigner, Dr. Jeff Jensen, Kristin Wyatt, and David Kyle
Snoqualmie tribal member Bethany Fackrell and UW Bothell student Sofia Tang sample water for eDNA in Zackuse Creek, photo provided by Dr. Jeff Jensen
Kokanee Environmental DNA Study Collaboration with the Snoqualmie Tribe and University of Washington Bothell
UW Bothell student Dan Nguyen preparing eDNA samples for analysis, photo provided by Dr. Jeff Jensen
By Dr. Jeff Jensen, Three Rivers Trout Unlimited Volunteer Leader
The Three Rivers Chapter of Trout Unlimited supplied financial and logistical support of a study conducted by students at the University of Washington (UW), Bothell campus. Environmental DNA (eDNA) is DNA that is shed by organisms into their environment. Scientists are able to detect the presence, and even estimate numbers, of a species by filtering water and looking for eDNA of target organisms.
During winter and spring, students at the UW Bothell undertook a study of eDNA in Laughing Jacobs Creek – a stream where our chapter conducts fry counts every year. The aims of the study were to see if:
The strength of the eDNA signal was corelated to the number of fry we were catching in the traps on a given night.
We could detect the presence of kokanee eggs and young while still under the gravel.
We could detect events such as the beginning of hatching when more eDNA is likely to be released.
As many members of our chapter know very well, fry trapping is a labor-intensive process. The use of eDNA sampling could provide a relatively easy way to supplement our current fry counts and to extend our sampling to additional streams.
Results were mixed in this initial study. Students were able to detect kokanee fry in the streams, but not consistently and the strength of the eDNA signal did not obviously correlate to the numbers of fry caught in the trap. This could reflect differences in stream flow (we have the data, but not yet analyzed) or other environmental variables. Likewise, students were able to detect presence of kokanee DNA in water samples taken before migration began, but not consistently. Pending additional funding, this study will continue next year with some refinement to sampling and, in particular, adjustments to laboratory techniques for extracting and detecting eDNA in the samples.
Newly emerged Lake Sammamish kokanee fry - source of the eDNA, photo provided by Dr. Jeff Jensen
Kokanee monitoring results, compiled by Kristin Wyatt
Kokanee Fry Monitoring - Final Counts
This spring, volunteers donated a total of 1,112 hours over the course of 409 nights to monitor kokanee fry on Ebright, Laughing Jacobs, and Lewis Creeks. Thank you to all who helped!
Lake Sammamish clean up, photo provided by Trout Unlimited and Mid-Sound Fisheries
Lake Sammamish habitat restoration, photo provided by Trout Unlimited
Lake Sammamish Park Clean Up - July 5th
How best to celebrate our nation’s independence? Considering adding a little stewardship to your holiday weekend! Join us on July 5th from 11 am to 1 pm at Lake Sammamish State Park to help clean up after the festivities on the 4th. For more information and to register to volunteer, go to https://www.eventbrite.com/e/5th-of-july-clean-up-tickets-924029425887.
Lake Sammamish Urban Wildlife Refuge Partnership
By Alix Lee-Tigner, Trout Unlimited Lake Sammamish Urban Wildlife Refuge Partnership Coordinator
Summer is in full swing around the watershed and our Lake Sammamish Urban Wildlife Refuge Partnership friends are hosting all kinds of events to get you out to play, learn, serve and work. Want to give back and care for our local parks? Join a cleanup event at Lake Sammamish State Park or join a restoration work party to dig some invasives. Interested in taking a stroll to learn about wildlife? Go for a bird walk or take a deep dive to learn about nature’s engineers – beavers! If your kids are looking for a hands on project, join a Washington State Parks ranger to build a critter. We’re all about helping you connect with nature and inspiring our community to be good stewards of our shared watersheds. Find your next adventure at https://www.lakesammamishrefuge.org/upcoming-events.
Lake Sammamish from Ebright Creek, photo provided by Natasha Kacoroski
Lake Sammamish Weed Management Study Update
Largemouth bass (Micropterus salmoides), a nonnative predator fish in Lake Sammamish, photo provided by David Kyle
By David Kyle, Trout Unlimited Lake Washington Basin Program Manager
Trout Unlimited (TU) has been a leader in aquatic weed management in Lake Sammamish for almost five years. This effort was initiated in response to data generated from the Kokanee Work Group’s (KWG) Technical Program that identified that kokanee salmon fry entering the lake had very poor survival to adulthood. Predation, especially by non-native warmwater gamefish, was identified as a concern by our local Salmon Recovery Board (WRIA8) which spurred a top-down direct removal of these fish by Washington Department of Fish and Wildlife (WDFW) and co-managers. TU wanted to complement the top-down approach by engaging in bottom-up management targeting the habitat, aquatic weeds in the nearshore areas, that provided essential support to these predators.
Over the last few years, TU has shown that removing these weeds is effective to displace these non-native fish by up to 99% in treatment areas and we are now working on refining our treatment approach to find an effective approach for long term control. Our hypothesis is that we are able to significantly reduce the habitat provided by non-native aquatic weeds to non-native warmwater gamefish it will result in a decline in their populations reducing predation mortality of all juvenile salmon in the lake.
Aquatic weeds in Lake Sammamish, photo provided by David Kyle
This summer we selected three treatment areas for our research. They are located off Timberlake Park (Issaquah), Weowna Park (Bellevue), and Sammamish Landing (Sammamish). We are utilizing two different herbicides, the first being “SonarOne” which is a systemic herbicide applied in a granular form to Timberlake Park which occurred on June 5, 2024. The second is Diquat “Tribune” which we used last summer but needed to refine our application approach at the Weowna Park and Sammamish landing which is scheduled for July 23, 2024. TU will be conducting effectiveness monitoring post treatment to evaluate the approach.
If you have any questions, reach out to David Kyle at dkyle@tu.org.
Fly fishing instruction, photo provided by Three Rivers Trout Unlimited
Connecting Youth to Coldwater Fisheries
Following the play-learn-serve-work model of engagement, we partner with Compass Outdoor Adventures to connect youth to coldwater fisheries conservation by providing fly fishing instruction at their Explorer Camp. For six days over the summer, members volunteer to teach basic fly casting skills to 4th and 5th graders. At the end, campers have the get to apply their fresh skills by catching bluegills in a pond. The experience provides a unique opportunity for youth to have fun on the water, learn something new, and start to care about coldwater fish.
Volunteer Appreciation BBQ Recap
Our annual BBQ to thank volunteers for their service this past year was held on Saturday, June 1st. Approximately 30 people attended for food, fly fishing experiences, and fun. Thank you to all the volunteers, members, and Trout Unlimited staff that supported with the event with food, drinks and activities. Special shout-outs to Austin Elliot for bringing gear and teaching fly tying, and Jeff Norman for setting up a course and teaching fly casting.
Photos (above and below) provided by David Kyle.
Fishing For Laughs
Question: How much tackle can an angler acquire before their partner throws them out?
Answer: I don’t know, but I think I’m getting close!
Support Us
Volunteer. Help out with operations (such as writing for this newsletter!), activities, and events. There’s a diverse range of ways and levels to get involved (like sharing a favorite fish joke!). If interested, reach out to admin@threerivertu.org.
Donate to the Three Rivers Chapter of Trout Unlimited. Your contribution helps fund chapter operations and activities such as Lake Sammamish Kokanee Fry Monitoring, our annual Project Healing Waters Fly Fishing Fishout, and more.
