Landscape configuration impacts the area of spring space use and survival of female sage-grouse

Abstract

ContextLandscape composition and configuration are essential factors for species distribution and persistence. Disturbance changes landscapes and can impact individuals' movement and space use based on mobility with tradeoffs between resource acquisition and survival.ObjectivesWe evaluated how spring space use and survival of female sage-grouse varied depending on the composition and configuration of disturbances within sagebrush and non-sagebrush dominated habitats, and whether the size of spring neighborhoods affected survival.MethodsWe created annual spring neighborhoods for individual female sage-grouse using location data from GPS-marked birds. We calculated the proportion, clumpiness, and interspersion and juxtaposition index (IJI) for each cover class within each neighborhood. We used linear mixed and Cox proportional hazards models to examine the interactive effects of composition and configuration on the area of space use and cumulative survival.ResultsSpring neighborhood size decreased when the proportion and interspersion of non-sagebrush and sagebrush cover was high but increased when interspersion was low. Neighborhood size decreased when interspersion and proportion of anthropogenic footprint was high but increased when proportion was low. Sage-grouse survival decreased as the proportion of anthropogenic footprint increased, regardless of configuration. Survival decreased when the proportion of juniper cover was high, and interspersion was moderate. Females that spent more time on nest had smaller neighborhood sizes and were more likely to survive during the spring season. However, there was no effect of neighborhood size on survival.ConclusionsOur results indicate that heterogeneity of habitat and disturbance reduces spring neighborhood size and decreases spring survival of female sage-grouse. These results suggest that management actions should focus on reducing pinyon-juniper where interspersion is high and reducing or removing anthropogenic disturbance near sage-grouse breeding areas.