Estimates of Breeding Bird Populations in the Sheyenne National Grassland, North Dakota

Authors

Mary Ann Cunningham, Vassar CollegeFollow
Douglas Johnson, United States Geological Survey, Northern Prairie Wildlife Research CenterFollow
Daniel N. Svingen, United States Department of Agriculture, Forest Service, Bismarck, North DakotaFollow

Date of this Version

3-2006

Document Type

Article

Citation

The Prairie Naturalist (March 2006) 38(1): 39-56

Associate editor for ornithology: Gregory A. Smith

Comments

Copyrght 2006, the authors. Used by permission

Abstract

We conducted a two-year survey of breeding birds in the Sheyenne National Grassland, North Dakota, to estimate total populations of breeding birds. The Grassland is of interest because it provides wildlife habitat and recreational birding opportunities. Indicated breeding pairs were counted on 100-m wide belt transects during morning surveys from late May to early July in 2002 and 2003. We surveyed approximately 6 to 7% of the Grassland each year. The most abundant species in both years were grasshopper sparrow (Ammodramus savannarum), red-winged blackbird (Agelaius phoeniceus), claycolored sparrow (Spizella pallida), Savannah sparrow (Passerculus sandwichensis), and common yellowthroat (Geothlypis trichas). Overall, grassland birds were more abundant, and woodland birds were more diverse. Population estimates differed between years, especially for less-common species and wetland species. ln comparison to a previous assessment derived from birding records, our results were more quantitative and gave higher numbers for widespread species. Conversely, our methods produced lower numbers for species that were secretive, nocturnal, locally abundant but not widespread, or most active outside of our lateMay to early-July survey period.