Wednesday April 22, 2026
Northwest Sportsman —
WDFW will run a pilot suppression study on three species of bass in Grays Harbor’s Chehalis River this spring to see if it can help reduce Chinook smolt predation there.
They’ll be electroshocking in the 10 miles of the river around Centralia and Chehalis, where summer water temperatures present a persistent core of optimal habitat for smallmouth, largemouth and rock bass.
These three nonnative species now represent the vast majority of the four main predatory fish species in the river system, having replaced native northern pikeminnow in that role since 2007, and managers are particularly concerned about their consumption of young Chinook.
This new study follows on tagging and tracking work with 120 smallmouth in 2024 and 2025 and stomach sampling performed in 2021 and 2022. According to preliminary estimates shared by a WDFW biologist in a Chehalis Basin Board presentation last month, Chinook represented 15 percent of the diet of smallies, and 41 percent of sampled bronzebacks’ stomachs contained the important salmon species.