Selected for FY24 funding under PLCI umbrella project.
The goal of this project is to assess lamprey in a newly reconnected and restored floodplain by monitoring seasonal migration patterns and habitat use by northwest lamprey species, including their respective life stages. The recently completed Steigerwald Lake Reconnection Project added nearly 1,000 acres of wetted floodplain to the Columbia River by reconnecting the lake with lower Gibbons Creek, which was previously
isolated and disconnected behind levees. Northwest lampreys (Pacific and Lampetra species) use these areas for rearing and migration, so floodplain disconnection and barriers can serve as a significant threat to lamprey in the Lower Columbia and Mainstem Columbia RMUs. The seasonal use of these newly reconnected areas by lamprey is largely unknown in the lower Columbia River basin. Lamprey habitat use will be assessed post-reconnection of the floodplain over multiple years, and passive detection of tagged lamprey will provide opportunities to continue assessment well after the two years outlined in this proposal. As large-scale restoration projects and flow management continue in the lower Columbia River, this information will help inform best practices for habitat restoration and water management by assessing the timing and magnitude of lamprey movement and habitat use associated with restoration at Steigerwald Lake NWR. This work will provide a baseline information on the use of these complex habitats by multiple species and life stages of lamprey, since reconnected habitats can have large seasonal and annual changes in water levels and temperatures that may influence access and use, and some newly flooded areas may not initially have substrates suitable for lamprey rearing.