Recovery Planning for Endangered Species Act-listed Pacific Salmon: Using Science to Inform Goals and Strategies

Endangered and threatened populations of Pacific salmon (Oncorhynchus spp.) in the United States span major freshwater and marine ecosystems from southern California to northern Washington, Their wide-ranging habits and anadromous life history exposes them to a variety of risk factors and influences, including hydropower operations, ocean and freshwater harvest, habitat degradation, releases of hatchery-reared salmon, variable ocean productivity, toxic contaminants, density-dependent effects, and a suite of native and non-native predators and competitors. We review the range of analyses that form the scientific backbone of recovery plans being developed for Pacific salmon listed under the U.S. Endangered Species Act. This process involves: identifying the appropriate conservation units (demographically independent Evolutionarily Significant Units [ESUs] and their populations), developing viability criteria for Pacific salmon populations and overall ESUs, and using coarse-resolution habitat analyses and life-cycle modeling to identify likely consequences of alternative actions proposed to achieve recovery. Adopting this wide breadth of analyses represents a necessary strategy for recovering Pacific salmon and a model for conservation planning for other wide-ranging species.