Targeting conifer removal to create an even playing field for birds in the Great Basin

Abstract

The encroachment of pinyon-juniper woodlands into sagebrush habitat in the Great Basin Ecoregion of the western USA, represents a potential source of habitat degradation for sagebrush-associated wildlife species. To restore sagebrush habitat, managers are conducting large-scale conifer removal efforts within the Great Basin, particularly within Greater Sage-Grouse (Centrocercus urophasianus) priority areas for conservation. Such large-scale habitat modification efforts may result in unintended ecological trade-offs for wildlife. To investigate these trade-offs, we used community science data to develop species distribution models for two sagebrush and three pinyon-juniper associated bird species of conservation concern in the Great Basin. We evaluated the predictive performance of our models with an independent dataset of presence locations derived from systematic monitoring programs. We then simulated conifer removal across the Great Basin and mapped habitat gains and losses for our study species. Despite differing land cover associations, 31%–51% of suitable habitat for our study species coincided with Greater Sage-Grouse priority areas for conservation. Our conifer removal scenario increased suitable habitat by 6%–17% for sagebrush associates and reduced habitat by 11%–41% for pinyon-juniper associates. We identified areas of the Great Basin where conifer removal expanded habitat for sagebrush associates without concurrent habitat loss for pinyon-juniper associates. Our results provide guidance for conducting vegetation management in the Great Basin while addressing the habitat needs for multiple focal species. Our methods, which use freely available community science data and geospatial layers, can easily be transferred to other species and ecoregions.