Qualitative species vulnerability: Model sensitivity to climate and spatial parameters

Natural resource managers model plant and animal climate vulnerability to efficiently plan and prioritize conservation actions. We assessed a commonly used online decision support tool, NatureServe's Climate Change Vulnerability Index (CCVI) and its sensitivity to different generations of climate models, socioeconomic climate scenarios, and different types and scales of spatial data. Our goal was to help mangers better interpret CCVI species vulnerability rankings and provide a workflow for generating the required climate metrics when those data are not already calculated. We found vulnerability scores were much larger when using an older generation as compared to a newer generation of climate projections, especially for water associated species. Socioeconomic climate scenarios were very important and resulted in differences of 130% between optimistic and pessimistic scenarios. Hence, we caution when comparing across studies to consider the generation of climate models and scenarios because the scores may not be directly comparable. The online tool was robust to the type and scale of spatial data. However, this data is only applied in calculating exposure and is not included in species specific sensitivity via adaptive capacity. Consequently, we suggest that managers use range size as an index of adaptive capacity when interpreting similar scores. Overall, we find the species climate vulnerability model supported by NatureServe a valuable and robust assessment that is easy to use and provides an objective method for prioritizing conservation action and justifying these actions to policy makers and the general public.