Horicon Marsh in southeastern Wisconsin attracts major concentrations of migratory waterfowl and supports a diverse assemblage of breeding bird species. Ridges near the marsh may be potentially productive sites for wind generation facilities. This study evaluates seasonal and microgeographic patterns of bird activity in the vicinity of Horicon Marsh, with the long term goal of estimating probabilities of collisions between birds and wind generators. Height above ground, distance from the observer, and flight direction were recorded for all birds detected during ten-minute point counts. Data were collected during spring migration, summer, and fall migration periods.
Results demonstrate clear patterns of activity.
Spatial and temporal variation in distributions reflect the importance of the marsh and its surroundings to birds and provide guidance for minimizing the impacts of wind generators on migratory and resident species. Strongest gradients of distribution occur in the autumn. Certain directions from the marsh also appear to be used more heavily than other directions, at least partly correlated with the patterns of habitat in the surrounding landscape. I studied the abundance and species composition of small mammals in hybrid poplar plantations, bean fields, corn fields, Conservation Reserve Program grasslands, and woodlots in the northcentral United States during July and August 1994. Species richness was highest in hybrid poplar and woodlot and lowest in bean.