Program in Ecological Physiology
Capability/Technical Service - Evaluation of water diversion structure screening technology.
Definition. Given the apparent untenable staus of many wild Pacific salmon populations, the role of hatchery stocks as a conservation tool has been increasingly debated. Numerous reviews of hatchery practices have recommended new practices concerning everything from release strategies to feeding methods that might improve the performance, especially survival to return as adult spawners, of fish produced from NFH programs.
Evaluation of Water Diversion Screen Criteria for Pacific Lamprey
Effective screening criteria are essential to prevent impingement and entrainment of petitioned Pacific lamprey in water diversion structures at the Pacific Region's NFHs, agricultural drainage ditches, and hydropower facilities. Existing criteria were based on and developed for salmon species, such as Chinook, and questions have arisen as to whether existing criteria could protect the declining Pacific Lamprey from impingement and entrainment at fishery facilities in Pacific Northwest watersheds. Using current generic salmon screening criteria as a baseline, the Center's Applied Research Program in Ecological Physiology conducted experiments to determine what risks, if any, the current water diversion screens pose to Pacific lamprey petitioned under the Endangered Species Act. The study has been completed and a final report has been submitted the USFWS Oregon Fish and Wildlife Office.
Partners USFWS Oregon Fish and Wildlife Office
Evaluation of Alternative Screen Technology for Carson NFH
Water Diversion Structures
Brook trout, considered an invasive species in the Pacific Northwest, have been found within the primary water source for Carson NFH. As a result production and stocking goals may be restricted in order to minimize the spread of brook trout to other aquatic systems. The fish screens at Carson NFH have been slated for replacement; however, the pore size must not allow brook trout entry into the NFH. The study’s objective was to examine brook trout just after hatch, when they are the smallest size, to determine the most appropriate sized screen to be used at Carson NFH. We hatched fertilized brook trout eggs and take morphometric measurements on the emergent fish and determined the smallest pore size for fish screens to effectively exclude brook trout from the Carson NFH. A final report was provided to Carson NFH.
Partner USFWS Carson NFH