Field-level spatial factors, associated edges, and dickcissel nesting ecology on reclaimed lands in Texas

Surface-mined land reclamation creates grass and shrub lands that provide important wildlife habitat, particularly for disturbance-dependent birds. Declines in disturbance-dependent birds have been observed for 30 years, emphasizing the importance of proper reclamation strategies. Understanding the influence of spatial factors on nesting ecology of avian populations can improve restoration strategies on reclaimed mines. We evaluated the influence of spatial factors on nest site selection, nest success, and nest parasitism of dickcissels (Spiza americana) on two sites reclaimed as wildlife habitat on the Big Brown Mine, Freestone County, Texas, in 2002–2003. We found 119 nests, 14 of which were parasitized by the brown-headed cowbird (Molothrus ater). Dickcissels were more likely to select nest sites farther from riparian areas and closer to brush-encroached areas. Nest success was not clearly explained by one or few variables. Parasitism was more likely to occur near riparian areas and roads. For these reasons, we suggest the establishment of larger wildlife habitat blocks, which would provide more field-interior habitat for dickcissels and similar species.