Grassland bird habitat selection in Northwest Illinois

摘要: The regional and national population declines of grassland birds have attracted much attention. The primary cause of these declines is habitat loss mainly as a result of agricultural intensification. The Conservation Reserve Program (CRP), intended to take marginal land out of crop production, and a growing interest in prairie restoration has led to an expansion of grassland habitats in some areas. This study was designed to examine grassland bird use of various grassland habitats in northwestern Illinois in order to develop management recommendations to benefit grassland birds.Most previous studies indicate that vegetation structure is far more important than species composition of the plant community for grassland birds (Herkert et al. 1993). This idea is certainly true when different plant species have the same growth form or when different management practices produce different vegetation structure from the same plant species. On the other hand, a common expectation in ecology is that diversity begets diversity. In other words, areas with differing plant species composition should also have different bird communities and, possibly, areas with greater plant diversity will support a greater diversity of birds. While several studies have examined grassland bird communities in native and non-native grasslands (Sutter and Brigham 1998, Davis and Duncan 1999, Washburn et al. 2000, Ludwig et al. 2001), none have examined the influence of plant species diversity on grassland bird diversity in detail.