Seasonal Habitat Use by Greater Sage-Grouse (Centrocercus urophasianus) on a Landscape with Low Density Oil and Gas Development.

Mindy B Rice,Liza G Rossi,Anthony D Apa,Francisco Moreira

doi:10.1371/journal.pone.0165399

Abstract

Fragmentation of the sagebrush (Artemisia spp.) ecosystem has led to concern about a variety of sagebrush obligates including the greater sage-grouse (Centrocercus urophasianus). Given the increase of energy development within greater sage-grouse habitats, mapping seasonal habitats in pre-development populations is critical. The North Park population in Colorado is one of the largest and most stable in the state and provides a unique case study for investigating resource selection at a relatively low level of energy development compared to other populations both within and outside the state. We used locations from 117 radio-marked female greater sage-grouse in North Park, Colorado to develop seasonal resource selection models. We then added energy development variables to the base models at both a landscape and local scale to determine if energy variables improved the fit of the seasonal models. The base models for breeding and winter resource selection predicted greater use in large expanses of sagebrush whereas the base summer model predicted greater use along the edge of riparian areas. Energy development variables did not improve the winter or the summer models at either scale of analysis, but distance to oil/gas roads slightly improved model fit at both scales in the breeding season, albeit in opposite ways. At the landscape scale, greater sage-grouse were closer to oil/gas roads whereas they were further from oil/gas roads at the local scale during the breeding season. Although we found limited effects from low level energy development in the breeding season, the scale of analysis can influence the interpretation of effects. The lack of strong effects from energy development may be indicative that energy development at current levels are not impacting greater sage-grouse in North Park. Our baseline seasonal resource selection maps can be used for conservation to help identify ways of minimizing the effects of energy development.

Highlights

Fragmentation from energy development may result in changes in land cover and could alter the spatial patterns of a species’ habitat use [1]
We found that the summer season exhibited the most differences from the breeding and winter seasons based on mean values including a lower proportion of sagebrush and a higher proportion of grass, riparian, and irrigated agriculture in the presence buffers and the presence buffers being closer to irrigated agriculture (Table 2)
The GRSG we studied in North Park selected similar habitat variables during the winter and breeding seasons

Summary

Introduction

Fragmentation from energy development may result in changes in land cover and could alter the spatial patterns of a species’ habitat use [1]. GRSG habitat associations have been well documented at multiple scales and are strongly tied to sagebrush landscapes utilization of those landscapes can differ depending on the season and the bird’s life stage [5]. Seasonal habitat use is an important consideration when developing models to predict habitat use as GRSG use distinct seasonal habitats throughout their annual cycle [2]. Developing these seasonal habitat maps for GRSG is a necessary component of managing human disturbance [6], but even more important in areas where development has not yet begun

Methods

Results

Conclusion