Pat DeHaan, Conservation Geneticist at the U.S. Fish & Wildlife Pacific Region Abernathy Fish Technology Center, contributed as a co-author to this recent article in Global Change Biology.
The study evaluated whether patterns of allelic richness were related to climatic variation and habitat features in 130 bull trout populations from 24 watersheds across the Columbia River Basin. It then determined whether bull trout genetic diversity was related to climate vulnerability at the watershed scale, which was quantified on the basis of exposure to future climatic conditions projected for the 2040s and existing habitat complexity. The results revealed that populations located in the most upstream headwater areas had the greatest genetic diversity. Allelic richness was positively related to habitat patch size and complexity, and negatively related to maximum summer temperature and the frequency of winter flooding. These relationships suggest that climatic variation influences evolutionary processes in this threatened species, and that genetic diversity will likely decrease due to future climate change.