Projected range shifting by montane mammals under climate change: implications for Cascadia's National Parks

We examined potential impacts of climate change over the next century on eight mammal species of conservation concern in western Washington State, under four warming scenarios. Using two species distribution models, including a logistic regression-based model and the "maximum entropy" (MaxEnt) model, we predicted the location and extent of the potential current and future range of each species based on a suite of environmental and geographical variables. Both models projected significant losses in range size within the focal area over the next century across all warming scenarios. Projections suggest that future ranges of high elevation species are likely to shrink inward and upward rather than shifting into new areas, and the average range elevation of most species is projected to increase significantly over time. Future projections for higher elevation species largely agreed across species distribution models, global climate model data, and carbon emission scenarios, although projections for lower elevation species were less consistent. The high elevation of the major national parks in this region is likely to aid in their ability to continue to support these species, and they are predicted to continue to act as important protected refuges, even while species' ranges may shrink dramatically elsewhere.