Is habitat restoration targeting relevant ecological needs for endangered species? Using Pacific Salmon as a case study

摘要

Conservation and recovery plans for endangered species around the world, including the US Endangered Species Act (ESA), rely on habitat assessments for data, conclusions and planning of short and long‐term management strategies. In the Pacific Northwest of the United States, hundreds of millions of dollars ($US) per year are spent on thousands of restoration projects across the extent of ESA‐listed Pacific salmon—often without clearly connecting restoration actions to ecosystem and population needs. Numerous decentralized administrative units select and fund projects based on agency/organization needs or availability of funds with little or no centralized planning nor post‐project monitoring. The need therefore arises for metrics to identify whether ecosystem and species level restoration needs are being met by the assemblage of implemented projects. We reviewed habitat assessments and recovery plans to identify ecological needs and statistically compared these to the distribution of co‐located restoration projects. We deployed two metrics at scales ranging from the sub‐watershed to ESA listing units; one describes the unit scale match/mismatch between projects and ecological concerns, the other correlates ecological need with need treated by projects across units. Populations with more identified ecological concerns contained more restoration effort, but the frequency of ecological concerns in recovery plans did not correlate with their frequency as restoration targets. Instead, restoration projects were strongly biased towards less expensive types. Many ESA‐listed salmon populations (78%) had a good match between need and action noted in their recovery plan, but fewer (31%) matched at the smaller sub‐watershed scale. Further, a majority of sub‐watersheds contained a suite of projects that matched ecological concerns no better, and often worse, than a random pick of all project types. These results suggest considerable room for gains in restoration funding and placement even in the absence of centralized planning. This analytical approach can be applied to any species for which habitat management is a principle tactic, and in particular can help improve efficiencies in matching identified needs with explicit management actions.