Grassland bird response to recent loss and degradation of native prairie in central and western South Dakota

Abstract

ABSTRACT Central and western South Dakota contain some of the largest intact blocks of mixed-grass prairie in North America, but conversion to row crops has accelerated sharply in recent years and existing grasslands have been further degraded by introduced plant species and the presence of anthropogenic woodlands. Our objective was to simultaneously investigate the effects of relatively recent habitat loss and degradation on grassland bird communities at the local, patch, and landscape scales. Specifically, to determine how 1) local- (vegetation structure, introduced plant coverage), 2) patch- (patch size, shape, and tree edge) and 3) landscape- (proportion of grassland surrounding surveyed sites) level habitat characteristics affect occurrence and density of six grassland bird species. We surveyed birds on 288 native grassland sites in 29 counties throughout central and western South Dakota. We calculated multiple metrics of habitat degradation and loss at the local, patch, and landscape scales and used...