Selection of anthropogenic features and vegetation characteristics by nesting Common Ravens in the sagebrush ecosystem

Observations of Territorial Breeding Common Ravens Caching Eggs of Greater Sage-Grouse

“…Observations from three common raven nest sites reported here were collected during the execution of two larger studies: 1) a resource selection study for nesting common ravens conducted during 2007-2009 on Department of Energy lands located in southeastern Idaho Howe et al 2014) and 2) an ongoing greater sage-grouse demography and nest predation study located in the Tuscarora Mountains of north central Nevada (U.S. Geological Survey unpublished data). Both study areas are high-desert sagebrushsteppe landscapes with varying degrees of habitat fragmentation and alteration by industrialization, multiple land-use activities, and wildfires.…”

“…However, ultimate factors related to habitat loss and fragmentation often associated with cropland conversion, urban expansion, wildfire, and invasion of nonnative vegetation (Schroeder et al 1999(Schroeder et al , 2004Crawford et al 2004;Knick and Connelly 2011) are more likely to regulate greater sage-grouse populations at large spatial scales. Nevertheless, land-use practices that artificially enhance common raven nesting opportunities, such as power line development (Knight and Kawashima 1993;Steenhof et al 1993;Howe et al 2014) across contiguous or fragmented sagebrush ecosystems, could result in reduced demographic performance for sensitive species such as greater sagegrouse through means such as increased risk and hyperpredation (Courchamp et al 2000) of nests and chicks. Coupled with other low population vital rates (Schroeder 1997;Schroeder et al 1999), this effect may limit population recruitment and maintenance of greater sage-grouse populations.…”

Greater Sage-Grouse (Centrocercus urophasianus) select habitat based on avian predators, landscape composition, and anthropogenic features

“…The decline of sage-grouse invariably includes a multitude of complex interactions between habitat, predator density, and anthropogenic factors (Crawford et al 2004, Moss et al 2010, Hess and Beck 2012b, Dinkins et al 2014b, Howe et al 2014. We examined predation and coyote removal effects in a central, non-fringe sage-grouse population, constraining the application of information based on our results to populations with similar limiting factors.…”

Influence of Wildland Fire Along a Successional Gradient in Sagebrush Steppe and Western Juniper Woodlands

“…Our study focused on sage-grouse survival, but future studies that address nest and brood success in relation to trees would be beneficial. For example, common ravens (Corvus corax) (Coates and Delehanty, 2010) also tend to avoid foraging and nesting in juniper woodlands (Coates et al, 2014a;Howe et al, 2014) but are highly likely to nest in single trees within shrub-dominated environments (Dunk et al, 1997;Coates et al, 2014a;Howe et al, 2014).…”

“…For example, important resources to sage-grouse such as food and concealment cover decrease disproportionately as the percent of pinyon-juniper overstory increases Miller et al, 2005;Miller et al, 2011). Additional tall vertical structures (such as trees) that provide perching and nesting habitat in an otherwise flat landscape can increase risk of avian predation (Coates et al, 2014a;Howe et al, 2014), which sage-grouse may perceive as a threat that changes with the density of trees on the landscape.…”