Estimating spatial variation in greater sage-grouse lek buffers using seasonal space use models
Greater sage-grouse (Centrocercus urophasianus) management relies on the identification and protection of core habitat for the species. Core areas are often centered on leks where the potential impacts of anthropogenic development and other disturbances can be evaluated based on buffer distances around active leks. While buffer distances have been quantified for some regions, sage-grouse space-use patterns vary across their range, and thus one-size-fits-all buffer distances are likely inappropriate for most regions.
Greater sage-grouse (Centrocercus urophasianus) are a sagebrush obligate species occupying sagebrush ecosystems across much of the western United States. The health and long-term persistence of sage-grouse populations remains of high conservation concern because the distribution of sagebrush has declined and become more fragmented over time. In addition, sage-grouse are increasingly susceptible to interactions between environmental stressors and anthropogenic development and disturbance. A key management strategy for greater sage-grouse involves the identification and protection of core habitat areas centered on leks, from which movements and seasonal home ranges emanate. The potential impacts of development and other disturbances can be characterized based on the degree of overlap with buffers around active leks. The buffer distances represent relative probabilities of an area or habitat being utilized by sage-grouse. To date, the application of buffers range-wide have been based on expert opinion or, more recently, distributions of sage-grouse habitat utilization for some regions where it has been quantified. However, space use patterns (for example, distances traveled from leks) are known to vary across the sage-grouse range, and one-size-fits-all buffer distances are likely to be biased for most regions across the range.
This project proposes to develop a method to estimate variation in buffer distances across landscapes, based on different movement and distribution patterns of sage-grouse populations in relation to leks. Updated buffer distances can better inform the overlap of grouse space use as a function of lek proximity with underlying habitat potential, when evaluating potential impacts. This information is critically important for managers seeking to determine if land use activities or anthropogenic development (for example, energy developments and infrastructure) might affect localized populations. Our results will form the basis for needed decision support tools and can be used to update current knowledge gaps regarding potential habitats used by sage-grouse in relation to leks, inform region-specific lek buffers, and establish the foundation for an annually varying sage-grouse distributional surface product that would have wider application to other regions beyond the pilot study extent.
Objectives
- Compile sage-grouse radio and satellite telemetry data, spanning California and Nevada, into a comprehensive database for kernel density analysis.
- Evaluate regional variation in effective lek buffering distances based on space use distributions gathered from telemetry data.
Implications
For buffer distances to be effective tools for the management of sage-grouse, species distribution models need to account for non-uniform distribution of leks and be able to differentiate between occupied and unoccupied habitat. Incorporating the probability of sage-grouse occupancy into buffers helps inform more effective land use and infrastructure permitting and siting decisions. Furthermore, because dispersal distances from activity centers like leks can vary, our goal is to provide specific data to managers regarding effective lek buffer distances for their region. This work can inform land-use decisions regarding the siting and permitting of infrastructure projects, energy development, mining, restoration activities, and other types of landscape treatments.
Greater sage-grouse (Centrocercus urophasianus) management relies on the identification and protection of core habitat for the species. Core areas are often centered on leks where the potential impacts of anthropogenic development and other disturbances can be evaluated based on buffer distances around active leks. While buffer distances have been quantified for some regions, sage-grouse space-use patterns vary across their range, and thus one-size-fits-all buffer distances are likely inappropriate for most regions.
Greater sage-grouse (Centrocercus urophasianus) are a sagebrush obligate species occupying sagebrush ecosystems across much of the western United States. The health and long-term persistence of sage-grouse populations remains of high conservation concern because the distribution of sagebrush has declined and become more fragmented over time. In addition, sage-grouse are increasingly susceptible to interactions between environmental stressors and anthropogenic development and disturbance. A key management strategy for greater sage-grouse involves the identification and protection of core habitat areas centered on leks, from which movements and seasonal home ranges emanate. The potential impacts of development and other disturbances can be characterized based on the degree of overlap with buffers around active leks. The buffer distances represent relative probabilities of an area or habitat being utilized by sage-grouse. To date, the application of buffers range-wide have been based on expert opinion or, more recently, distributions of sage-grouse habitat utilization for some regions where it has been quantified. However, space use patterns (for example, distances traveled from leks) are known to vary across the sage-grouse range, and one-size-fits-all buffer distances are likely to be biased for most regions across the range.
This project proposes to develop a method to estimate variation in buffer distances across landscapes, based on different movement and distribution patterns of sage-grouse populations in relation to leks. Updated buffer distances can better inform the overlap of grouse space use as a function of lek proximity with underlying habitat potential, when evaluating potential impacts. This information is critically important for managers seeking to determine if land use activities or anthropogenic development (for example, energy developments and infrastructure) might affect localized populations. Our results will form the basis for needed decision support tools and can be used to update current knowledge gaps regarding potential habitats used by sage-grouse in relation to leks, inform region-specific lek buffers, and establish the foundation for an annually varying sage-grouse distributional surface product that would have wider application to other regions beyond the pilot study extent.
Objectives
- Compile sage-grouse radio and satellite telemetry data, spanning California and Nevada, into a comprehensive database for kernel density analysis.
- Evaluate regional variation in effective lek buffering distances based on space use distributions gathered from telemetry data.
Implications
For buffer distances to be effective tools for the management of sage-grouse, species distribution models need to account for non-uniform distribution of leks and be able to differentiate between occupied and unoccupied habitat. Incorporating the probability of sage-grouse occupancy into buffers helps inform more effective land use and infrastructure permitting and siting decisions. Furthermore, because dispersal distances from activity centers like leks can vary, our goal is to provide specific data to managers regarding effective lek buffer distances for their region. This work can inform land-use decisions regarding the siting and permitting of infrastructure projects, energy development, mining, restoration activities, and other types of landscape treatments.