2017-006-00

Non-native predator recruitment reduction

Non-native predator fishes require stable spawning and early rearing environments to maintain productive populations. For example larval walleye need near zero velocity rapidly warming water during in the first few weeks after hatch to successfully recruit to the population. Further, smallmouth bass nesting can be disrupted by changes in water velocity and temperature. Opportunities exist to use the hydropower system to create short-term changes in the habitat characteristics that are critical for the reproduction and recruitment of these non-native salmon predators. Well-timed short-term changes in water surface elevation at McNary Dam may be able to flush larval walleye from currently used recruitment areas (zero velocity/warm) into habitats where they will not survive (swift current/cold). Smallmouth bass nesting in similar habitats can be disrupted by these same changes in water depth, velocity, and temperature. The proposed project will occur in three phases. In the first phase, existing hydrodynamic models will be used to predict changes in habitat characteristics based on a variety of water surface elevation changes and durations and the full experimental design and statistical analyses plan will be developed. In the second phases, the vulnerability of critical life stages of non-native predators will be determined. The third phase of the project will consist of multiple management action implementation tests with rigorous before, during, and after monitoring and data analyses and reporting.

Benjamin Dick

John Skidmore

Proposed - Project Status Report

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Predation

Predator Removal

Anadromous: 0.0%   Resident: 100.0%   Wildlife: 0.0%

2017 Individual Review (Public Tags)

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