Conservation of Sage‐grouse Critical Habitat and Implications for Prairie Songbirds

Abstract

ABSTRACTA popular approach for conserving multiple organisms in a given region is to identify one or more umbrella species. Identifying and managing for species that have a high degree of overlap in their habitat requirements with a broader suite of organisms is expected to enhance the effectiveness of conservation actions when resources are limited. The greater sage‐grouse (Centrocercus urophasianus) has received considerable attention as a potential umbrella species for shrub‐steppe flora and fauna in the core of its range. However, the extent to which conserving sage‐grouse habitat benefits mixed‐grass prairie songbirds in the northern portion of its range is unclear. We compared abundance of grassland songbirds within grasslands designated as sage‐grouse critical habitat by the Canadian federal government, and within a 1.6‐km buffer of adjacent habitat in southwestern Saskatchewan, Canada in 2016 and 2017. We also quantified relationships between bird abundance and gradients of vegetation structure. Lark bunting (Calamospiza melanocorys) abundance was 3 times greater within sage‐grouse critical habitat, whereas chestnut‐collared longspur (Calcarius ornatus), Baird's sparrow (Centronyx bairdii), and Sprague's pipit (Anthus spragueii) abundance was 1.6–1.8 times greater outside of these areas. The abundance of grassland specialists was negatively associated with total shrub and silver sagebrush (Artemisia cana) cover, both of which characterize sage‐grouse critical habitat in Canada at both landscape and local scales. Furthermore, characteristics of vegetation structure associated with grassland generalists overlapped with characteristics of vegetation structure that defined greater sage‐grouse critical habitat. Conservation of greater sage‐grouse critical habitat in Canada is likely to have a positive influence on shrub‐dependent or shrub‐tolerant species, such as lark bunting. The conservation of open, native grasslands within greater sage‐grouse critical habitat could benefit grassland specialists, however, any changes in the current management that increases the cover of exotic species, silver sagebrush, and other shrubs will negatively affect grassland specialists. We recommend that protection and management activities be targeted towards greater sage‐grouse, Sprague's pipit, and chestnut‐collared longspur to maximize the conservation of mixed‐grass prairie songbirds and minimize the number of focal umbrella species required. © 2021 The Wildlife Society.