Greater sage‐grouse use of mechanical conifer reduction treatments in northwest utah

Abstract

A potential consequence of climate change, altered fire regimes, and a legacy of resource exploitation in western North America is increased displacement of desirable sagebrush (Artemisia spp.) communities by invasive plant species. Annually, an estimated 90,000 ha of sage-grouse (Centrocercus spp.) habitat is degraded by pinyon (Pinus spp.) and juniper (Juniperus spp.; PJ) encroachment. Sage-grouse responses to conifer encroachment may include avoidance of otherwise available habitats, lek abandonment, and subsequent population declines. Thus, restoration of PJ encroached sage-grouse habitats that exhibit intact sagebrush understories is a priority conservation action. However, better information is needed regarding sage-grouse response to these management actions. We used sage-grouse fecal pellet surveys and radiotelemetry location data to identify vegetation and landscape attributes that may influence sage-grouse use of PJ removal treatments completed using mechanical methods. Use of PJ removal treatments by sagegrouse was positively associated with irrigated pasture and alfalfa (Medicago sativa) hay within 1 km (b ¼ 7.69, SE ¼ 5.58, P ¼ 0.17) and negatively associated with PJ canopy cover (b ¼ À1.52, SE ¼ 0.84, P ¼ 0.07) within 500 m of treatments. Percent cover of mesic habitats and sagebrush canopy were greater within 1 km of treatments where sage-grouse were detected; however, these relationships were weak because of large variability in conditions across sites. Our results document sage-grouse use of 9 of 16 mechanical PJ removal treatments examined in an encroached sagebrush landscape and suggest that mechanical PJ removal treatments should be sited adjacent to occupied sage-grouse habitat in areas that minimize surrounding PJ cover. Ó 2017 The Wildlife Society.

Predicting greater sage‐grouse habitat selection at the southern periphery of their range

“…Somewhat surprisingly, conifer cover did not appear among the top‐ranked variables in any of our models, despite conifer encroachment negatively impacts sage‐grouse survival (Coates et al., 2017), sage‐grouse lek activity decreases with increasing conifer stand cover (Baruch‐Mordo et al., 2013), and sage‐grouse select for areas where conifer removal treatments have been implemented (Cook et al., 2017; Sandford et al., 2017). The relationship we found with conifer indicated slight selection for areas with no conifer cover and moderate avoidance of areas with high conifer cover (), which is consistent with previous evidence.…”

“…and Juniperus spp.) encroachment and cheatgrass ( Bromus tectorum ) invasion (Connelly et al., 2000; Cook et al., 2017; Crawford et al., 2004; Dahlgren et al., 2016; Sandford et al., 2017). However, further research will be needed to identify thresholds for sagebrush patch sizes that render them insufficient for providing habitat or enhancing connectivity.…”

Seasonal movements of greater sage-grouse populations in Utah: Implications for species conservation

“…First, because brood movements were confined to the available habitat space, increased habitat space adjacent to current breeding habitat could readily be used by sage‐grouse. For example, sage‐grouse in Utah have been shown to occupy areas of sagebrush encroached by conifers post‐tree removal (Cook , Sandford et al ). This response has been immediate in areas that exhibited limited habitat space (Frey et al ).…”

Influence of Juniper on Montezuma Quail Habitat Use in Texas

“…In addition, these observations of a population response to removal of dense juniper are similar to those reported for other galliformes that can be negatively affected by conifer encroachment, such as greater sage‐grouse ( Centrocercus urophasianus ). This species has experienced habitat loss due to increased conifer encroachment (Severson et al 2017) and evidence exists documenting greater sage‐grouse response to expansion and removal of pine‐juniper or conifer woodlands (Baruch‐Mordo et al 2013, Cook et al 2017, Severson et al 2017).…”