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Submitted to: Journal of Wildlife Management
Publication Type: Peer Reviewed Journal Publication Acceptance Date: 7/16/2010 Publication Date: 4/22/2011 Citation: Augustine, D.J. 2011. Habitat selection by mountain plovers in shortgrass steppe. Journal of Wildlife Management. 75(2):297-304. Interpretive Summary: Mountain plovers breed in grasslands of the western Great Plains, including public lands in Weld County, Colorado, which were considered to be a key breeding area for the species prior to the 1990s. However, few studies in eastern Colorado have considered the use of black-tailed prairie dog colonies or prescribed burns by mountain plovers during the breeding season. During 2008 – 2009, I conducted surveys in four habitats on public lands in Weld County, CO, consisting of (1) prescribed burns, (2) active black-tailed prairie dog colonies, (3) black-tailed prairie dog colonies affected by epizootic plague in the past 1 – 2 years, and (4) moderately-grazed rangeland with no recent history of fire or prairie dogs. Mountain plover densities were similar on active black-tailed prairie dog colonies (average of 6.8 birds km-2) and prescribed burns (average of 5.6 birds km-2), and were an order of magnitude lower on rangeland sites grazed by cattle but lacking recent disturbance by prairie dogs or fire (0 birds km-2 on randomly-selected rangeland sites; 0.3 birds km-2 for combined random and non-random rangeland sites). Mountain plover densities were intermediate (2.0 birds km-2) on sites where black-tailed prairie dogs had been removed by plague in the past 1 – 2 years. These findings suggest that both prescribed burning and management that maintains or expands active black-tailed prairie dog colonies in shortgrass steppe can enhance breeding habitat for mountain plovers. Technical Abstract: Much of the breeding range of the mountain plover occurs in shortgrass steppe and mixed-grass prairie in the western Great Plains of North America. Studies of mountain plovers in shortgrass steppe during the 1970s and 1990s focused on public lands in Weld County, Colorado, which were considered to be a key breeding area for the species. These studies were conducted in shortgrass steppe lacking black-tailed prairie dogs (Cynomys ludovicianus) and prescribed fire, but the role of these two grassland disturbance processes has increased substantially over the past 15 years. During 2008 – 2009, I used radial distance point count surveys to estimate mountain plover densities in four habitats on public lands in Weld County, CO, consisting of (1) prescribed burns, (2) active black-tailed prairie dog colonies, (3) black-tailed prairie dog colonies affected by epizootic plague in the past 1 – 2 years, and (4) moderately-grazed rangeland with no recent history of fire or prairie dogs. Mountain plover densities were similar on active black-tailed prairie dog colonies (X = 6.8 birds km-2, 95% CI = 4.3 – 10.6) and prescribed burns (X = 5.6 birds km-2, 95% CI = 3.5 – 9.1), and were an order of magnitude lower on rangeland sites grazed by cattle but lacking recent disturbance by prairie dogs or fire (0 birds km-2 on randomly-selected rangeland sites; 0.3 birds km-2, 95% CI = 0.1 – 0.8 for combined random and non-random rangeland sites). Mountain plover densities were intermediate (2.0 birds km-2, 95% CI = 0.8 – 5.0) on sites where black-tailed prairie dogs had been removed by plague in the past 1 – 2 years. These findings suggest that both prescribed burning and management that maintains or expands active black-tailed prairie dog colonies in shortgrass steppe can enhance breeding habitat for mountain plovers. |
