NEST-SITE SELECTION, NEST DESIGN AND NEST-ENTRANCE ORIENTATION IN BACHMANS SPARROW

Nest sites of Bachman's Sparrows (Aimophila aestivalis) in pine planta tions in central Arkansas had greater tree density and less forb cover than non-nesting sites, but nesting sites could not be separated from non-nesting sites using multivariate analyses. At the microhabitat le vel, sides of nests had greater vegetation density between 0-60 and 0- 180 cm than random points or nest entrances. Most nests were either pa rtially (38%) or completely (55%) domed and most entrances were orient ed to the north. Nest design was not affected by degree of concealment , nesting year, or nesting season, bur grasses and forbs were taller a round domed nests than at partially domed nests. No significant relati onships among nest success, nest design, vegetation structure of the m acrohabitat or microhabitat were found. This suggests that random pred ation and/or variation in predator density may have existed.