Hybridization between native and invasive trout is increasing in the West

The original story was published by the USGS.

New research provides evidence that stocking non-native fish in conjunction with on-going climate change may accelerate the rate of hybridization between species. This may reduce wild fish performance and lessen resilience in a warming world.

College of Fisheries and Ocean Sciences professor Peter Westley was part of a team of national researchers who synthesized climate predictions for Rocky Mountain ecosystems, genetic data from 12,878 individual fish, and detailed historical stocking records from 1924-1980 for approximately 200 million introduced rainbow trout. The study found hybridization is increasing over a broad geographic region despite ending stocking practices nearly 40 years ago. Data going back to the 1980s show that 50 percent of sites with long-term data show increases in hybridization, the majority of which were initially genetically pure. The study highlights vulnerability of sites that are close to historical stocking locations and cautions that cold headwater streams may not be resistant to the invasion of foreign genes.

More information on this research can be found in the USGS press release or in the published journal article.

ADDITIONAL CONTACT: Peter Westley, pwestley@alaska.edu, 907-474-7458.

Close-up of non-hybridized westslope cutthroat trout Oncorhynchus clarki lewisi) from the Flathead Basin in Montana. This fish, its scientific name inspired by Lewis and Clark, represents the genetic and life history diversity of western trout by surviving extreme climatic variation over millions of years. Photo by Jonny Armstrong. Public domain.

This entry was posted in Climate Change, Fisheries, Uncategorized. Bookmark the permalink.

Leave a Reply

Your email address will not be published. Required fields are marked *


You may use these HTML tags and attributes: <a href="" title=""> <abbr title=""> <acronym title=""> <b> <blockquote cite=""> <cite> <code> <del datetime=""> <em> <i> <q cite=""> <strike> <strong>