Some fish live in our rocky streams year-round, others prefer the Columbia River, and many move back and forth to the ocean. Unfortunately, numerous fish species in our area are in critical danger due to dams, dredging, and logging practices which warm streams and fill them with sediment.
Lampreys are boneless fish (skeletons made of cartilage). All of our lampreys are born in freshwater streams and grow up in burrows in those streams, filtering small organisms out of the water. Some species (the Pacific Lamprey and Western River Lamprey) move out into the ocean in adulthood and become parasites of large fish, while other species (Western Brook Lamprey and Pacific Brook Lamprey) stay in the streams their entire lives and never become parasites.
All lamprey species in our area have seen dramatic declines due to dams, water pollution, and degraded stream quality due to logging and dredge mining. They are listed as Species of Concern federally and as Critical-Sensitive species in Oregon.
Columbia County has numerous species of nonnative fish that have been introduced to our waters from eastern USA or Europe, including American Shad, Mosquitofish, Perch, Green Sunfish, Bluegill, Pumpkinseed, Smallmouth Bass, Largemouth Bass, Crappie, Yellow Bullhead, Brown Bullhead, European Carp, Grass Carp, and many others. I chose to omit them from this guide.