Warming drives poleward range contractions of Beringian endemic plant species at high latitudes

Aim: Species are expected to disperse poleward in response to climate change. For species that are endemic to the high latitudes, this implies that many in the future would face a "no-where-to-go" situation as they are currently occupying the northernmost portion of the continent. Further, because endemism may arise from a combination of physical barriers, climate, and geological history, the persistence of many species may require spatial matching of multiple environmental factors within a limited dispersal space. Thus, it is not clear how endemic species might spatially adjust their distributions in response to climate change and whether there are future climate change refugia for these species.

Location: Northwest North America                               

Taxa: Plants

Time period: Current and the future (2040)

Methods: We used ensemble bioclimatic models to evaluate drivers and directional patterns of future change in the distributions of 66 North American Beringian and Amphi-Beringian species currently occurring in Alaska and the Yukon. We explored the spatial pattern of species richness, losses and climate change refugia across the region.

Results: More than 80% of the species showed northward shifts in their latitudinal centroids under intermediate warming and are expected to shift their range northward by more than 140km on average by 2040. Additionally, more than 60% were projected to experience range contractions and up to 20% of the species would have the potential to expand their ranges by more than 100%.

Main conclusions: Suitable habitat for endemic species in northwest North America is expected to decline significantly, especially for species occupying the Arctic tundra. Although the models identified several potential refugia from future climate change, especially at high latitude and elevation, whether the species would be able to colonize new habitats on their own and/or capitalize sufficiently on in situ refugia remains a pertinent conservation question.