Fish need water. While minimum flows and other emergency-response approaches might save some fishes during crises, such “bucket-based” approaches are insufficient in the long-term….The current drought underscores the need to rapidly identify flows that protect fish and other aquatic species. Although specific instream flow needs of many species are unknown, managing for a subset of species (the umbrellas identified by our approach) could speed the process by focusing attention on the flow needs of a few species that confer protection to others.