Abundance of Fish and Wildlife
Are Columbia River Basin fish species abundant, diverse, productive, spatially distributed, and sustainable?

Adult Pacific Lamprey Trends and Abundance

Adapted from Luzier, C.W., H.A. Schaller, J. K. Brostrom, C. Cook-Tabor, D.H. Goodman, R.D. Nelle, K. Ostrand, and B. Streif. 2011. Pacific Lamprey (Entosphenus tridentatus) Assessment and template for Conservation Measures. U.S. Fish and Wildlife Service, Portland, Oregon. 282 pp.
View trends and abundance by clicking on regions. To view counts at the dam click on green icon.
Lower Columbia / WillametteUpper ColumbiaSnake RiverMid-ColumbiaWillamette FallsBonnevilleThe Dalles DamSherars FallsJohn Day DamThree Mile DamMcNary DamIce Harbor DamLower Monumental DamLittle Goose DamLower Granite DamPriest Rapids DamWanapum DamRock Island DamRocky Reach DamWells Dam
Managers and researchers of Pacific lamprey in the Columbia River Basin divide the mainstem Snake and Columbia River Region into four geographic sub-regions (i.e., Snake Basin, Upper Columbia, Mid-Columbia, and Lower Columbia). Evaluating Pacific lamprey status and trends for many watersheds in the mainstem Snake and Columbia River Region is difficult as there is a lack of targeted monitoring efforts, harvest records, and reliable dam counts. For much of the Pacific lamprey current range of distribution, managers and researchers have to rely on best professional judgment and partial surveys to estimate abundance and short-term trends. Based on the data collected to date, the Snake River and Upper Columbia sub-regions are considered at high risk as there are no adjacent low risk populations to aid in population re-establishment. The lack of nearby stable populations in the Lower Columbia, as well as select watershed in the Middle Columbia a sub-region, has led to these regions being classified as imperiled.