Small‐bodied fish species from the western United States will be under severe water stress by 2040

Abstract

Human need to appropriate freshwater in combination with climate change has intensified the rapid decline in freshwater biodiversity. Based on 216 currently imperiled freshwater species in the United States, the Southwest, and the Rocky Mountains, were predicted to experience the highest increase in future water stress for 2040 in 41 minor watersheds. Resident-small species in the Southwest, found in single locations (21.6%) or on local level (62.2%), were listed as endangered (n = 37) and are predicted to experience severe water stress increases by 2040. Endangered species in the Rocky Mountains (n = 9), were found on a basin or local level (33.3%), exhibiting predominantly potamodromous behavior (66.7%). Furthermore, many endangered species in key regions lack life-history data (41%). Our results highlight that determining priority of species for conservation using biodiversity as an indicator may not be useful for identifying future impacts to imperiled species, since many regions undergoing high water stress did not coincide with biodiversity hotspots.