An Assessment of Conservation Opportunities Within Sagebrush Ecosystems of US National Parks and Wildlife Refuges

Abstract

Strategic plans for landscape-scale conservation are preferable to ad-hoc decisions that lack evidence and cohesion. The Sagebrush Conservation Design (SCD) is a biome-wide geospatial decision-support framework for a “Defend the Core, Grow the Core” strategy. We mapped US National Parks and Refuges across the SCD to guide “defend and grow” investments. We summarized amounts of sagebrush “Core Sagebrush Areas” (CSAs) and “Growth Opportunity Areas” (GOAs) areas within Parks and Refuges and asked: 1) Where are the Parks and Refuges that contain substantial sagebrush resources and that are likely to retain these resources under future climate conditions? 2) What is the trend of loss across CSAs and GOAs within Parks and Refuges? 3) Do trends immediately surrounding Parks and Refuges correlate with those within? 4) Which Parks and Refuges contain the most CSAs and GOAs? 5) What will it cost to defend and grow CSAs in these places?

Approximately 127 000 ha (313 824 ac) or 75% of CSAs was lost from Parks and 87 000 ha (214 982 ac) or 25% was lost from Refuges since 1998. Climate change is likely to reduce CSAs and GOAs in the northeastern and southwestern biome periphery and at low elevations. Similar trends of loss were observed surrounding Parks and Refuges. This underscores the ‘outside-in’ nature of changes occurring in the biome as fires, conifer encroachment, and invasive grasses move rapidly through permeable landscapes. Ten Parks and 10 Refuges contain >95% of CSAs and GOAs and exhibit climate durability under our examined future scenario, revealing how investments can be prioritized. Within this list, however, estimated costs of recommended actions (e.g., annual grass suppression) greatly exceeds plausible available amounts, emphasizing the need to use strategic prioritization within high-priority units. We examined application of the SCD for guiding “open” and “defined” investment decisions for Park and Refuge case studies.