Science Supporting Management of Aquatic Species Under the Endangered Species Act

We address 3 categories of conservation effort and scientific analysis relevant for cold-water fishes that have particular application under the U.S. Endangered Species Act: assessment of overall risk to a species; long-term recovery planning; and evaluation of effects of specific actions or perturbations. We recommend scientists conducting such conservation analyses develop a conceptual model that links climate, habitat, ecosystem, and species response to changing conditions, to organize analyses and future research. We also suggest that current climate conditions are not appropriate for projections used in ESA analyses and that long-term projections of climate-change effects provide temporal context as a species-wide assessment provides spatial context. Climate change should not be discounted solely because the magnitude of projected change at a particular time is uncertain when directionality of climate change is clear.  As a whole, conservation for cold-water fishes will be most effective when a range of potential outcomes is considered, and when the overall resilience and resistance of species to climate changes is enhanced.  Mechanisms for increasing such resistance include emphasizing conservation of genetic and phenotypic diversity, of habitat in areas not currently occupied but likely to become important, and using adaptive management.