Pacific Lamprey Research and Restoration Project : Annual Report 2001.

Pacific lamprey (Lampetra tridentata) has significantly declined along the Oregon coast and in the Columbia River Basin (Downey et al. 1993; Close and Jackson 2001). Declines in adults can be partially attributed to hydroelectric dams, which have impeded passage of adult Pacific lamprey in the Columbia and Snake rivers, thus effecting larval recruitment in the basin. Adult pacific lamprey also declined in numbers in the Umatilla River, a tributary of the Columbia River. In addition to hydro power dams in the Columbia River, habitat alterations and chemical treatments have been involved in the collapse of Pacific lamprey populations in the Umatilla River. To initiate the restoration effort, CTUIR began developing a restoration plan in 1998. The goal of the lamprey research and restoration project is to restore natural production of Pacific lampreys in the Umatilla River to self-sustaining and harvestable level. This report is summarizing the studies and restoration efforts concluded in 2001