Wildlife Conservation Sunflower Plots and Croplands as Fall Habitat for Migratory Birds

摘要

Agricultural fields are often overlooked as post-breeding and migratory bird habitat, even though many species use row-crop fields in the northern Great Plains. We monitored bird use, crop and non-crop vegetation characteristics and abundance, and land use around (≤2.4 km) 35 8-ha Wildlife Conservation Sunflower Plots (WCSP) and one commercial sunflower and non-sunflower row-crop field, paired with each WCSP, in fall 2004 and 2005. We excluded four species of blackbirds from our analysis that commonly form large foraging flocks and ubiquitously use agricultural fields. A diverse community of migratory birds used WCSP and commercial sunflower compared to other non-sunflower crops in North Dakota. Both WCSP (mean = 24.4 birds/ha, SE = 2.7) and commercial sunflower (mean = 12.7 birds/ha, SE = 1.7) harbored greater densities of birds (P \u3c 0.01) than did other non-sunflower row crops (mean 5 7.2 birds/ha, SE = 1.1). Migratory birds were more strongly associated with vegetation within fields, such as crop density (+), non-crop plant abundance (+) and crop height (+), than surrounding land uses (0–2.4 km from WCSP). We recommend management practices to maximize WCSP for fall bird habitat and discuss economic considerations for WCSP implementation as a wildlife habitat / blackbird damage management system.