Cooperative Fish and Wildlife Research Units Program: Oregon
Education, Research and Technical Assistance for Managing Our Natural Resources

The Nisqually River Delta serves as essential feeding and rearing habitat for diverse fish and wildlife species. Between 1996 and 2009, the Nisqually Indian Tribe and the Billy Frank Jr. Nisqually National Wildlife Refuge restored over 365 hectares of estuarine habitat to tidal influence, with the goal of supporting juvenile Chinook salmon and other estuary-dependent species. Restoration monitoring from 2009 to 2015 showed significant improvements in habitat connectivity between the Nisqually River mainstem and the restored estuary, particularly at mid-to-high tide. However, the restoration’s most recent areas (2009), located in lower-elevation and more subsided regions, have shown slow vegetation colonization and growth, raising concerns about long-term habitat viability in these zones. In light of the decadal anniversary of the 2009 restoration, the Tribe, Refuge, and USGS collaborated to gather new data, including LIDAR imagery (2020), aerial photography (2019), Surface Elevation Table (SET) readings (2019, 2021), and vegetation surveys (2019, 2021). These data supplemented earlier monitoring efforts and enabled a comprehensive evaluation of the restoration’s impact over time. We integrated habitat connectivity metrics, spatial data on sediment deposition and erosion, and vegetation growth patterns to gauge progress, identifying both achievements and ongoing challenges in habitat establishment. This study has provided critical insights that will directly inform future management strategies aimed at sustaining and enhancing habitats for sensitive fish and wildlife species, as well as supporting the long-term resilience of restored estuarine systems. Through this collaborative effort, we are building a robust foundation for data-driven habitat management that benefits the species dependent on the Delta’s unique and dynamic ecosystem.