Landscape dynamics of bird and small mammal communities in sagebrush-dominated mountain meadows: A hierarchical, multi-s

1. Landscape dynamics of bird and small mammal communities in sagebrush-dominated mountain meadows: A hierarchical, multi-scale study Elizabeth J. Johnson, Tammy L. Wilson, and John A. BissonetteUSGS Utah Cooperative Fish and Wildlife Research Unit INTRODUCTION Sagebrush ecosystems have been seriously influenced, over much of their range, by human use and are now considered one of the most endangered ecosystems in North America.Over 50% of western grassland and shrubland bird species are in decline, and some of these species live only in sagebrush. The majority of the studies of sagebrush habitats, however, have focused on low elevations, and the contribution of high-elevation sagebrush remains relatively unstudied. High-elevation sagebrush habitats, particularly sagebrush-dominated mountain meadows, may have been less affected by human activities than the sagebrush steppe found at lower elevations. Careful management and conservation of currently intact sagebrush-dominated mountain meadows may be a cost-effective supplement to the restoration of lower sagebrush-steppe. PRELIMINARY RESULTS GOALS & OBJECTIVES Determine the contribution of high elevation sagebrush steppe to bird and small mammal species diversity patterns and evaluate the use of these habitats by known sagebrush obligate and near-obligate species Elizabeth J. Johnson’s Objectives:Determine the relationship between meadow characteristics and species composition and relative abundances. Tammy L. Wilson’s Objectives:Assess the influence meadow arrangement on bird and small mammal diversity and density. • Mammals trapped: • 256 Deer Mice • 65 Least Chipmunks • 35 Great Basin Pocket Mice • 28 Uinta Chipmunks • 11 Southern Red-backed Voles • 7 Golden Mantled Ground • Squirrels • 7 Snowshoe Hares • 3 Uinta Ground Squirrels • 2 Long-Tailed Voles • 1 Short-Tailed weasel or Ermine • 1 Northern Pocket Gopher • Sagebrush species of concern identified in the first field season: • Brewer’s Sparrow (SO) • Least Chipmunk (SO) • Gray Flycatcher (SO) • Green-tailed Towhee (SNO) • Vesper Sparrow (SNO) *SO = sagebrush-obligate*SNO = sagebrush-near-obligate STUDY AREA The study area is located in the Bear River portion of the Wasatch Mountains of the Wasatch-Cache National Forest DISCUSSION A variety of sagebrush-obligates and near-obligates are found in high-elevation sagebrush, but not all of the species of concern were detected. Some, such as Greater Sage Grouse, may not have been detected using the above methods. Others, may not be using these areas or are in densities low enough to avoid detection. It appears that these areas are important for conservation, but cannot be used as a one-to-one substitute for low elevation habitat. Analysis of the meadow and landscape characteristics on species compositions and relative abundances has not yet been conducted. • METHODS • Meadows were randomly selected within the forested areas of the Wasatch-Cache National Forest. Fieldwork is being conducted from late spring through late summer in both 2003 and 2004 and include: • Variable distance bird point counts, also known as point transects • Small mammal trapping using Tomahawk, Sherman, and rat snap traps on 50 meter radius trap webs • Vegetation sampling including species lists, measuring shrub cover, shrub age state classification, and using Daubenmire frames • Spot checks of the surrounding matrix are done to ensure the accuracy of our remotely • sensed GIS data