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USGS · 70259639

Closing the conservation gap in the sagebrush biome: Spatial targeting and coordination are needed for conservation to keep pace with sagebrush losses

Abstract

Core sagebrush areas (CSAs), patches of high sagebrush ecological integrity, continue to decline despite significant conservation and restoration investments across the sagebrush biome. Historically, conservation decisions in the biome have been driven by wildlife species-specific demands, but increasing recognition of the scale of threats and the pace of ecosystem degradation has compelled a shift towards threat-based ecosystem management. Therefore, there is a need to evaluate the scale of conservation implementation relative to the rate of degradation or loss from specific threats to the biome to assess whether a conservation deficit exists. To this end, we: 1) quantified and compared the average hectares of conservation practices implemented annually relative to the hectares of CSA loss attributed to each threat; 2) evaluated the relative amount of conservation actions in core sagebrush areas, growth opportunity areas, and other rangeland areas; and 3) assessed how much additional conservation may be needed to stop CSA declines. We then quantified how better spatial targeting and enhanced coordination might reduce the total additional amount of future conservation needed, and evaluated how an influx of resources can close the conservation gap, or the deficit between the conservation needed to offset annual loss and degradation and the capacity for conservation implementation. We found that current rates of conservation (e.g., hectares treated annually) are markedly lower than rates of CSA loss (∼10% of average annual loss). Furthermore, most conservation actions, ∼90% for some treatment types, occurred outside of CSAs likely reducing the efficacy of these conservation actions at retaining and restoring intact sagebrush rangelands. Additionally, we found that conservation efforts will need to increase by more than an order of magnitude (at least 10x) annually to halt CSA declines. However, through better spatial targeting of conservation actions, the increase in conservation needed to stop CSA loss could be reduced by 70% or more. This analysis demonstrates the divergent futures that may await the sagebrush biome pending key decisions regarding conservation targeting, stakeholder cooperation, and the strategic addition of resources.

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BibTeXRIS

Tina G. Mozelewski, Patrick T. Freeman, Alexander V. Kumar, David E. Naugle, Elissa M. Olimpi, Scott L. Morford, Michelle I. Jeffries, David S. Pilliod, Caitlin E. Littlefield, Sarah E. McCord, Lief A. Wiechman, Emily J. Kachergis, Kevin E. Doherty. 2024. Closing the conservation gap in the sagebrush biome: Spatial targeting and coordination are needed for conservation to keep pace with sagebrush losses. https://doi.org/10.1016/j.rama.2024.08.016

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