Area Sensitivity in North American Grassland Birds: Patterns and Processes

Grassland birds have declined more than other bird groups in North America in the past - years (Vickery and Herkert , Sauer et al. ), prompting a wide variety of research aimed at understanding these declines, as well as conservation programs trying to reverse the declines (Askins et al. ). Area sensitivity, whereby the pattern of a species' occurrence and density increases with patch area (Robbins et al. ), has been invoked as an important issue in grassland-bird conservation, and understanding the processes that drive area sensitivity in grassland birds is a major conservation need (Vickery and Herkert ). Here, we review the literature on North American grassland bird species that is relevant to the following questions.