Pacific Lamprey Research and Restoration Project

Background and Goal

The Pacific Lamprey Research and Restoration Project was initiated in 1994 to address the alarming decline of Pacific Lamprey populations in the mid- to upper-Columbia and Snake River tributaries (Close et al. 1995). Historically abundant, Pacific Lamprey are a vital cultural and subsistence resource for Native American tribes in the Pacific Northwest and an important ecological component of inland river systems. Their decline not only disrupted ecological processes but also limited treaty-reserved fishing opportunities, forcing the four Columbia River treaty tribes to harvest lamprey only in lower Columbia River areas (CRITFC 2011, 2018, 2025).

The primary goal of the project is to restore Pacific Lamprey populations to self-sustaining, harvestable levels, while also generating actionable knowledge for recovery efforts across the region—particularly in the CTUIR-ceded area streams. The project supports this goal by conducting research that informs restoration strategies, benefiting efforts in other parts of the Columbia River Basin where lamprey have declined or disappeared, such as the Grande Ronde, Walla Walla, and Tucannon basins.

CTUIR’s work has been instrumental in shaping restoration strategies for the mid-Columbia drainage. Project staff have gathered essential data on historical and current lamprey abundance, habitat needs for each life stage, and factors limiting natural production. Additional areas of research include donor stock availability, population genetics, disease presence, migratory timing, and both adult and juvenile passage and homing behaviors.

Collectively, this work has generated critical insights into the biology and ecology of Pacific Lamprey throughout the Columbia River Basin, providing a strong foundation for ongoing and future restoration efforts.

UMATILLA BASIN
Since its inception in 1994, the Pacific Lamprey Research and Restoration Project has focused on two major components within the basin: 1) restoration activities involving translocating broodstock from the mainstem Columbia to increase larval lamprey abundance in the upper Umatilla River; and 2) understanding the biology and ecology of Pacific Lamprey.  In the coming year we propose to build upon these efforts to bring us closer to the ultimate goal of the project: restoring the natural production of Pacific lampreys in the Umatilla River to self-sustaining and harvestable levels.  

The Umatilla River basin was chosen by the Confederated Tribes of the Umatilla Indian Reservation (CTUIR) as the initial pilot restoration project for these reasons: 1) the Umatilla River historically produced a fishable population of lampreys, 2) restoration efforts for salmonids in the basin may help with overall Pacific Lamprey restoration, and 3) current population level of Pacific lampreys in the Umatilla River were extremely low. In 1998, CTUIR began developing a restoration plan. Historical abundance and distribution data were summarized from tribal elder and ODFW interviews, and larval abundance and distribution surveys were completed in the John Day, Umatilla, Walla Walla, Tucannon, and Grand Ronde rivers. In cooperation with Northwest Power and Conservation Council (NPCC), Columbia River Intertribal Fish Commission (CRITFC), U.S. Geological Survey (Columbia River Research Laboratory, (CRRL)), United States Fish and Wildlife Service (USFWS), and Oregon Department of Fish and Wildlife (ODFW), the Confederated Tribes of the Umatilla Indian Reservation (CTUIR) staff developed the restoration plan for the basin. Knowledge on the current and historical abundance, lamprey handling, transport, spawning, and outplanting of larvae were collected with experiments conducted to maximize the potential for the restoration of lampreys in the Umatilla River.

In 2000, CTUIR implemented a pilot translocation project in the Umatilla River. Translocation of adult Pacific Lamprey in the Umatilla River began in May 2000 with the release of 600 adults.  This was followed with intensive monitoring of several metrics of lamprey (spawning ground surveys, larval density surveys, documenting the number of up-migrating adults and out-migrating larvae) annually. Now in its twenty-sixth year, the pilot project continues to translocate sexually mature adult lamprey in an effort to increase larval densities in the upper basin. Results are showing initial success of habitat selection for spawning and rearing, increased larval and juvenile outmigrants and increasing volitional adult immigrants to the basin.

We will continue work to refine lamprey passage structures at Three Mile Falls Dam, and Feed diversion dams.  These structures have been in place for over 15 years.  We are employing new techniques and strategies to ensure these systems are working effectively and efficiently.

In 2026, we will continue efforts to monitor all life stages of Pacific Lamprey within the Umatilla River basin.  

The project has the following objectives for 2026 in the Umatilla River:
1.  Increase larval abundance in the Umatilla River by translocating/trap and hauling adult lampreys.
2.  Estimate lamprey abundance at index sites in the Umatilla River, and Meacham Creek.
3. Estimate the number of adult up-migrants entering the Umatilla River.
4. Estimate the number of out-migrating lamprey (larvae and metamorphosed) from the Umatilla River and continue juvenile PIT tag evaluations).
5. Monitor passage conditions at low-head irrigation diversions for adult and larval/juvenile lamprey.
6.  Refine adult lamprey passage structures at irrigation diversions on the Umatilla River.
7.  Report results to the funding agency.
8.  Publish findings in peer-reviewed journals and attend professional conferences.
9. Complete monitoring resources.org protocols for related work elements.

CEDED AREA LARVAL SURVEYS
Beginning in 2019, ceded area larval surveys were commenced in the ceded area rivers of the CTUIR with efforts focused to understand the current status of juvenile lamprey in the Grande Ronde, Tucannon, Walla Walla, and John Day river basins. This work will allow us to effectively compare other supplementation strategies (art.prop/translocation/control) underway in other basins.  These actions are called for within the Supplementation master plan document the tribes finalized in 2018 (CRITFC 2018).

In 2026, we have the following objectives for the ceded area surveys:
1. Continue to re-establish juvenile index sites (incorporating those from our 1999 surveys) in the Tucannon, Walla, Walla, John Day, and Grande Ronde basins.
2. Conduct larval electrofishing surveys at the index sites
3. Collect eDNA samples from tributaries within the ceded area.  This data will help provide presence/absence and distribution information.  


MASTER SUPPLEMENTATION PLAN

From 2012-2018, CTUIR, YN and CRITFC developed a Lamprey Master Supplementation Plan for the mid-upper Columbia River basin.  This plan is the driving force for supplementation efforts in the region.  The plans uses a phased approach with  laboratory, applied field experiments, analysis of results, and eventual production level implementation with adaptive management. This plan was approved by the ISRP and the NPCC in mid-2018. In 2019, The EA was completed and the BA was commenced through BPA EC.

For 2026, CTUIR will continue collaboration with Dr. Mary Moser to continue the refinement of methodology and criteria needed to implement Phase 1 of the Master Supplementation Plan for Lamprey.  Phase 1 work will continue at the Walla Walla Community College Water Environmental Center.  We will use a collaborative approach with Yakama Nation Fisheries, Mr. Ralph Lampman to advance this regional objective.  After EC clearance, in May 2021, we implemented Phase 2 applied field experiments with the first release of artificially produced lamprey in the Tucannon River.  For 2026, we will continue with releases of artificially propagated pro-larvae in the Tucannon River and begin upgrades to the repurposed SFWW ozone building for lamprey rearing.  

The project has the following objectives for 2026 for Master Plan related work:
1. Continue to advance (laboratory only) work related to artificial propagation research.
2. Spawn, incubate and rear up to 1,000,000 pro-larvae for release in the Tucannon River and monitor survival
3. Establish and estimate lamprey (pre and post re-introduction) abundance at index sites in the Walla Walla and Tucannon basins with genetic tissue samples collected from any larvae for future analysis.
4. Coordinate with agencies that are operating outmigration screw traps and conducting salmonid spawning surveys to properly identify, and collect biological data for individuals sampled. Provide support as needed.
5. Coordinate with local, state, tribal, and federal agencies for any necessary permits.