Changes In Relative Abundance Of Eastern And Western Meadowlarks Along A Transect Across Southern Wisconsin Surveyed In 1952-53 And 2003
David W. Sample, Wisconsin Department of Natural Resources, Bureau of Integrated Science Services, Monona, WI 53716; (608) 221-6351; FAX (608) 221-6353; david.sample@dnr.state.wi.us
Christine A. Ribic, USGS Wisconsin Cooperative Wildlife Research Unit, Department of Wildlife Ecology, University of Wisconsin, Madison, WI 53706
Wesley E. Lanyon, Lamont Curator of Birds Emeritus, American Museum of Natural History, New York, NY 10024
Michael J. Guzy, USGS Wisconsin Cooperative Wildlife Research Unit, Department of Wildlife Ecology, University of Wisconsin, Madison, WI 53706
John D. Dadisman, Wisconsin Department of Natural Resources, Monona, WI 53716
Sonya J. Knetter, USGS Wisconsin Cooperative Wildlife Research Unit, Department of Wildlife Ecology, University of Wisconsin, Madison, WI 53706
We lack knowledge of population changes for most nongame bird species prior to the USGS Breeding Bird Survey. We compared the relative abundance of Eastern and Western Meadowlarks (Sturnella magna and S. neglecta) across a 1,296 mi2 transect in southern Wisconsin surveyed in 1952-53 and 2003. Observers stopped on roadsides as close as possible to each section corner in the transect and recorded the number of Eastern and Western Meadowlarks; the dominant land use in each quarter of the horizon was also recorded. Both species declined between 1952-53 and 2003. The average number of Western Meadowlarks recorded per stop was 1.3 and 0.03 in 1952-53 and 2003, respectively, while the mean count of Eastern Meadowlarks per stop was 0.8 in 1952-53 and 0.3 in 2003. The mean number of horizon-quarters per stop where pasture (preferred Meadowlark habitat) was dominant decreased from 1.4 in 1953 to 0.2 in 2003. In 1952-53, Western Meadowlarks were more common than Eastern Meadowlarks in the western and central portions of the transect; Eastern Meadowlarks were dominant in the far eastern portions. In 2003, Western Meadowlarks were virtually absent from all but the westernmost portions, where Eastern Meadowlarks now reached their highest abundance. The western portion was the only area where pasture averaged above 0.5 horizon-quarters per stop. This study provides insight into the relationship of Meadowlark abundance and land use over an unusually long time span.