Greater Sage-Grouse Nest Observations Before and After Wildfire Disturbance in Northeastern California (2007-2018)

We monitored Greater Sage-Grouse (Centrocercus urophasianus; hereafter, Sage-Grouse) nests and various habitat characteristics at the nest locations near Susanville in northeastern California, crossing over into northwestern Nevada. We employed a before-after-control-impact (BACI) experimental design to account for spatiotemporal heterogeneity in the system and to derive estimates of relative change in survival parameters. Sage-Grouse nest survival decreased after the Rush Fire but decreased more in the burned area relative to the unburned area. Although female Sage-Grouse continued to occupy burned areas, nest survival was reduced from 52 percent to 19 percent. Using a BACI ratio approach we found that nest survival decreased approximately 51 percent in the burned area, relative to the unburned area, following wildfire. Habitat analyses were restricted to the post-fire period and found that female Sage-Grouse that nested within unburned areas selected for wider nesting substrate, taller perennial grass height, and greater low sagebrush canopy cover. Conversely, female Sage-Grouse that nested in burned areas used shorter sagebrush canopy cover than what was available across the entire study area, but showed stronger selection for perennial grass height than their unburned counterparts. Strong nest-site fidelity in Sage-Grouse may explain the continued use of suboptimal habitat in wildfire-altered landscapes, resulting in a reproductive cost, and overall reproduction well below replacement rate. Results suggest that fire suppression or rapid post-fire habitat restoration, especially within nesting habitat, may be essential to conserving robust Sage-Grouse populations into the future.

These data are supported by the following publication:
Dudley, I.F., Coates, P.S., Prochazka, B.G., O'Neil, S.T., Gardner, S., and Delehanty, D.J., In-press. Large-Scale Wildfire Reduces Population Growth in a Peripheral Population of Sage-Grouse. Ecosphere.