Thursday July 9, 2026
KGW8 —
New research from Washington State University Vancouver shows hatchery-raised fall Chinook salmon are less likely to return to spawn if they’ve been raised in noisy environments.
The work indicates that noise in a fish’s early life disrupts its ability to survive in the wild, and that the use of sound-dampening techniques in hatcheries could improve return rates, WSU said.
Inversely, salmon that began life in noise-protected environments were more likely to complete the journey to the ocean and back, researchers found.
“The hatchery system is really critical for the nation, ecologically and economically,” said Rikeem Sholes, a U.S. Fish and Wildlife fisheries biologist who led the research project as part of his graduate studies at WSU. “We spend millions upon millions of dollars raising these fish for various reasons, so we want to make sure that we’re sending them out with all their systems working so they have the best chance of making it back.”
The National Fish Hatchery System, comprised of 71 facilities nationwide, releases 125 million fish each year to help foster economic development, fulfill tribal trust obligations, and bolster endangered fish runs. However, hatchery-raised fish often exhibit lower fitness and survival compared to wild fish, and scientists are exploring hatchery environments for potential explanations.
One of those elements is noise. Hatcheries are noisy operations, with pumps, generators and aerators. They are also sometimes located near other sources of sound, such as roads. Past studies have linked noise exposure to hearing loss in some fish, disrupting their ability to perceive acoustic signals and survive in the wild.