Klamath Falls Field Station
Research Snapshot - Evaluation of the Williamson River Delta Restoration Project
The KFFS collaborated with seven other partners in a long-term research and monitoring program to assess the effects of restoring the Williamson River Delta on the early life stages of Lost River and shortnose suckers. The Williamson River Delta restoration is an innovative project of The Nature Conservancy that aims to improve habitat for native fishes and other wildlife around the mouth of the Williamson River. You can learn more about the project, including how explosives were used to breach levees, here.
The research and monitoring program provided essential information for ongoing management of the large-scale restoration project as about 7,500 acres of previously agricultural lands return to wetlands and open water. The thorough evaluation of the response of fish to the restoration will also be beneficial to land managers considering similar wetland restoration projects. Our research focused on determining how and when juvenile suckers used the restored habitat, how fish assemblages changed within the restored habitat as wetlands returned, and how the health and growth of suckers was affected by restoration activities.
- Determining the Portion of Restored Habitat Used by Age-0 and Age-1 Suckers, and the Changes in Habitat Use Over Time.
- Determining if Larval Suckers are Retained in Restored Habitats By Combining a Hydrodynamics Model with Data on the Ages and Densities of Larval Suckers (In collaboration with Tamara Wood of the USGS Oregon Water Science Center.
- Comparing Prey Availability between Restored Habitats and Adjacent Lake Habitats (In collaboration with James Carter of the USGS National Research Program).
- Comparing Fish and Benthic Invertebrate Assemblages between Restored Habitats and Adjacent Lake Habitats and Tracking Changes Over Time.
- Age-0 and age-1 suckers used nearly all of the restored habitats within the restoration project. Age-0 suckers used shallow, vegetated habitats in July and dispersed throughout the Delta and adjacent lake habitats during August and September. Age-1 suckers used stands of emergent vegetation in shallow water as cover from April to June, and then moved to deeper, less vegetated habitats in July and August.
- The prevalence of non-native and piscivorous fish species in restored habitats was similar to adjacent lake habitats.
- Juvenile suckers captured in restored habitats and adjacent lake habitats appeared to have similar levels of overall health and condition.
- Lake surface elevation, river discharge, and larval behavior all play a role in the retention of larval suckers within the Williamson River Delta.
- Burdick, S.M, and D.A. Hewitt. 2012. Distribution and condition of young-of-year Lost River and shortnose suckers in the Williamson River Delta restoration project and Upper Klamath Lake, Oregon, 2008–10—Final Report. U.S. Geological Survey Open-File Report 2012-1098, 52 p.
- Burdick, S.M., C. Ottinger, D.T. Brown, S.P. VanderKooi, L. Robertson, and D. Iwanowicz. 2009. Distribution, health, and development of larval and juvenile Lost River and shortnose suckers in the Williamson River Delta restoration project and Upper Klamath Lake, Oregon. U.S. Geological Survey Open File Report 2009-1287.
- Burdick, S.M., and D.T. Brown. 2010. Distribution and Condition of Larval and Juvenile Lost River and Shortnose Suckers in the Williamson River Delta Restoration Project and Upper Klamath Lake, Oregon: 2009 Annual Data Summary. U.S. Geological Survey Open File Report 2010-1216.
- Other reports are available here.