Ecoregions: Developed originally by Bailey (1995) and Environment Canada (Wiken, 1986), this data layer was modified by The Nature Conservancy (TNC) to be used in its Biodiversity Planning exercises in the process known as Ecoregional Assessments in the continental United States, Alaska, Hawaii and Canada. Several Ecoregions were modified from the original (Bailey, 1995) by TNC staff developing the aforementioned assessments. The modifications are based on ecological, bio-physical and political rationales; most changes are noted in the accompanying document. Changes to ecoregions in Canada were done mainly at the border with US territory, where Bailey (1995) ecoregions crossed over the country boundaries. This is the primary data set used in the definition of an assessment unit for the ecoregional assessment analytical process for North America.

In this analysis, resileince scores were stratified by ecoregion and geophysical setting.