Conserving Nature's Stage in the Pacific Northwest

The PNW Conserving Nature’s Stage project includes two studies. The purpose of the first (Buttrick et al 2015) was to identify the most resilient terrestrial sites in the Northwest U.S. that will collectively and individually best sustain native biodiversity even as the changing climate alters current distribution patterns. The second study of broad-scale landscape connectivity in the PNW (McRae et al 2016) complements the 2015 analysis by identifying areas likely to facilitate ecological flow—particularly movement, dispersal, gene flow, and distributional range shifts for terrestrial plants and animals—over large distances and long time periods. Both studies were funded by the Doris Duke Charitable Foundation and conducted by staff of The Nature Conservancy (Oregon and North America Region programs).


Conserving Nature’s Stage: Identifying Resilient Terrestrial Landscapes in the Pacific Northwest (2015)

To restate, the goal of this first study was to identify sites in the Pacific Northwest which best allow for adaptive responses by terrestrial animal species and vegetation communities to a changing climate. Collectively and individually, these sites are the most resilient – able to sustain terrestrial biodiversity even as the climate change alters current biogeographic patterns. The central tenet of our methods is that by mapping combinations of key geophysical features (“land facets”) that remain the most stable over time and evaluating them for certain landscape characteristics, we can identify the most resilient places in the terrestrial landscape in order to help guide future conservation investments. The landscape characteristics that engender resilience are twofold: (1) topoclimate, the local temperature and moisture conditions that result from underlying topographic properties such as slope, aspect, landform shape, and elevation; and (2) local permeability, the degree to which landscapes, encompassing a variety of landcover types, will sustain ecological processes and are conducive to the movement of many types of organisms. The project, funded by the Doris Duke Charitable Foundation (DDCF), was completed in two phases with a combined study area covering 97.3 million hectares (240.4 million acres) of the Pacific Northwest and northern California. Currently this work is focused on the terrestrial landscape but we and others hope to include freshwater and coastal habitats in the future.


Conserving Nature’s Stage: Omnidirectional Connectivity for Resilient Terrestrial Landscapes in the Pacific Northwest (2016)

This second study serves as a companion to Buttrick et al 2015. In the earlier work, sites with more local permeability and topoclimatic diversity were considered more resilient to climate change as they should have higher potential to allow organisms to access climatically suitable areas across short distances. Whereas in that case terrestrial resilience characteristics were measured at a local scale, in this complementary analysis on regional connectivity we identified areas in the same study area likely to facilitate ecological flow — particularly movement, dispersal, gene flow, and distributional range shifts for terrestrial plants and animals—over large distances and long time periods. Notably, this analysis represents a novel application of Circuitscape software (McRae et al 2008) in which algorithms from circuit theory are used to calculate the expected flow of species. The new algorithm incorporates a “moving window” component, yielding a continuous and core-free (“omnidirectional”) view of landscape connectivity. As a whole, this study does not incorporate projections of future climates, but does include a pilot analysis of movement across climate gradients.



Go to the website below for more information and updates, download the full report, access additional datasets, and get current information on associated land protection and outreach grants available in Oregon, Washington and Idaho. http://nature.ly/resilienceNW