Popham, G.P. & Gutiérrez, R.J. 2003: Greater sage-grouse Centrocercus urophasianus nesting success and habitat use in northeastern California. - Wildl. Biol. 9: 327-334.
From mid-March through mid-August 1998-2000, we studied greater sage-grouse Centrocercus urophasianus nesting habitat in northeastern California, USA. We located nest sites of 45 radio-marked hens, which had an average nest success of 40.2%. The radio-marked grouse used low sagebrush Artemisia arbuscula cover type less than expected; big sagebrush A. tridentata wyomingensis and mixed shrub cover types were used in proportion to their availability. Grouse used sites with habitat characteristics similar to random sites for nesting. However, successful nests differed from unsuccessful nests in several respects. Mean distance between nest and lek was greater for successful nests (× = 3,588 m, SE = 811 m, N = 20) than for unsuccessful nests (× = 1,964 m, SE = 386 m, N = 20). Rock cover was greater at successful nests (×` = 27.7%, SE = 4.6%) than at unsuccessful nests (× = 14.49%, SE = 3.04%). Total shrub height was greater at successful nests (× = 65.5 cm, SE = 4.7) than at unsuccessful nests (× = 49.2 cm, SE = 1.7). The height of visual obstruction was greater at successful nests (× = 40.2 cm, SE = 2.6) than at unsuccessful nests (× = 32.5 cm, SE = 2.0). Our results suggest that sage-grouse use more diverse vegetation than previously reported, and we conclude that either this represents a natural behaviour for sage-grouse in this area, or we observed a selection response to a landscape altered by human activity.
Key words: Artemisia tridentata wyomingensis, California, Centrocercus urophasianus, Galliformes, greater sage-grouse, nest site selection, radio-telemetry
Gail P. Popham*, Department of Wildlife, Humboldt State University, Arcata, California, USA 95521 - e-mail: firstname.lastname@example.org
R.J. Gutiérrez, Department of Wildlife, Humboldt State University, Arcata, California 95521, USA, and Department of Fisheries, Wildlife and Conservation
Biology, University of Minnesota, St. Paul, MN 55108, USA - e-mail: email@example.com
* Present address: California Department of Transportation, 1656 Union Street, Eureka, CA 95501
Corresponding author: R.J. Gutiérrez