Occurrence, Rarity and Climate Sensitivity Index, and Components of 29 Fishes Native to the Pacific Northwest, USA

These datasets include the components of and results from the Rarity and Climate Sensitivity Index (RCS) and occurrence records used to calculate the index for 29 stream fishes native to the Pacific Northwest (Washington, Idaho, Oregon) of the United States. The RCS is an index that ranks species’ intrinsic sensitivity to climate change based on their area of occurrence and climate niche breadth, the range of environmental conditions for a given species. The RCS uses point occurrences to calculate both metrics. We compiled point occurrences from a variety of sources. Final point occurrences were filtered for quality assurance and received expert review (details in occurrence dataset metadata). We calculated RCS metrics at two spatial grains: 1) Hydrologic Unit Code (HUC) level 12 watersheds and 2) 1 km buffered occurrence points and stream segment level. The area of occurrence for each species was calculated as the total watershed area of all HUC 12 watersheds containing any of the final set of occurrence points or the total area of 1 km buffer around the final set of occurrence points. We calculated climate niche breadth using two sets of environmental variables at both spatial grains, bioclimatic and stream level. Bioclimatic level was calculated by extracting annual mean precipitation, maximum temperature of the warmest month, and minimum temperature of the coldest month from the area of occurrence using the the Parameter-elevation Regressions on Independent Slopes Model (PRISM) dataset. Stream level was calculated by extracting mean August stream temperature, mean stream baseflow, and either predicted streamflow permanence probability or predicted streamflow permanence class from all streams within the watershed area of occurrence or the nearest stream to each point occurrence for the 1 km grain. Stream level data was extracted using compiled streamflow permanence, water temperature, and modeled streamflow data (Sando and Schultz, 2022). Climate niche breadth from both levels is calculated as the area-weighted standard deviation for each variable. The RCS is calculated from the scaled and combined species’ area of occurrence and climate niche breadth, such that an intrinsically sensitive species has a small area of occurrence and a narrow niche breadth.