Breeding bird communities of reclaimed coal-mine grasslands in the American midwest

摘要

We studied the breeding bird communities of 19 reclaimed surface coal-mine grasslands in southwestern Indiana in 1997-1998, using roadside point counts and off-road transects. The mine grasslands in this study were large, ranging from 110 to 3180 ha in area (median, 590 ha). Although dominated by a few Eurasian grass species, they supported diverse bird communities in which grassland-dependent species were prominent along with grassland-associated and successional scrub species. The mean abundances of species (relative to one another) on roadside and off-road counts were positively correlated. Red-winged Blackbirds (Agelaius phoeniceus), Eastern Meadowlarks (Sturnella magna), and Grasshopper Sparrows (Ammodramus savannarum) were present at >90% of point count locations. Other common species, in descending order, included Dickcissels (Spiza americana), Common Yellowthroats (Geothlypis trichas), Killdeers (Charadrius vociferus), Indigo Buntings (Passerina cyanea), Henslow's Sparrows (Ammodramus henslowii), Field Sparrows (Spizella pusilla), and Song Sparrows (Melospiza melodia). Brown-headed Cowbirds (Molothrus ater) were rare, as were seven grassland-dependent species that were near the edges of their geographic distributions.