Thursday November 5, 2026
Northwest Sportsman —
More than 8,000 bass were electroshocked out of a 9-mile section of the Chehalis River this summer as part of a suppression and abundance study that also aims to estimate how removals of the invasive fish will help reduce predation on native Chinook.
The data also told researchers that there are now more than 1,000 rock, smallmouth and largemouth bass per river kilometer – about six-tenths of a mile – that are large enough to chow down on the young salmon swimming in the Western Washington stream.
The multiyear study performed by WDFW focuses on the Chehalis between the mouths of the Newaukum and Skookumchuck Rivers, where warm summer water temperatures present a persistent core of optimal habitat for bass, and it follows up on bass tagging and tracking there in recent years.
That initial research found baby Chinook represented 15 percent of smallmouth diets in spring and summer, and 41 percent of bronzeback stomachs contained the important salmon species. The bass captured this summer will also be dissected to determine what was in their diet.