Thursday April 18, 2024
EurekAlert! —
Researchers who created “family trees” for nearly 10,000 fish found that first-generation, wild-born descendants of hatchery-origin Chinook salmon in an Oregon river show improved fitness.
The finding, based on data collected over 13 years, is encouraging for Chinook salmon recovery efforts, said Kathleen O’Malley, an associate professor at Oregon State University and the study’s senior author. In this study, fitness is measured by the number of adult offspring a fish produces, with higher fitness leading to more offspring.
“Previous studies have shown that hatchery-origin Chinook salmon have lower reproductive success relative to their natural-origin counterparts when they spawn in the wild, but this study looks beyond that,” said O’Malley, who directs the State Fisheries Genomics Lab.
“While our work doesn’t contradict the earlier findings, we found that the first-generation descendants of these hatchery-origin Chinook salmon produced more offspring than hatchery-origin salmon spawning alongside them in the river, meaning that reproductive success may improve in the wild as quickly as it declines in the hatchery.”