Dam removal frees fish to feed in the ocean

Bull trout in the Elwha River have been separated from the ocean for a century, but dam removal in 2012-14 has now freed them to head out to the ocean again. Analysis of stable isotope ratios reveals that bull trout now spend substantial time at sea eating marine prey before heading back to the Elwha River to spawn. This re-emergence of a long-lost life history variation after being landlocked for so many decades, shows that fish species can swiftly adapt and change their strategies when new opportunities arise. The work by SAFS Prof. Thomas Quinn and his coauthors was published in Environmental Biology of Fishes.

Back to Top