Grassland habitat in the Northern Prairie region of North America has been greatly reduced since historical times, and conversion to agricultural row-crop production has recently intensified this decline. Common Nighthawk (Chordeiles minor) nesting habitat includes grasslands and flat, gravel rooftops, but relative occurrence of nighthawks in these habitats in the Northern Prairie region has not been previously quantified. We conducted point counts at 396 sites within two study areas in South Dakota, Nebraska, and Iowa; an eastern region dominated by row-crop agriculture and a western region with more grassland within the landscape. We compared land cover at points where nighthawks were present between the two regions and found higher incidences of cropland and grassland in the western region and higher developed land cover in the eastern region. We also compared land cover surrounding points where birds were present vs. absent for both regions combined and found greater cropland around points without birds and greater developed land cover around points with birds. We used Generalized Linear Models (GLMs) with binomial distributions to examine nighthawk presence relative to landscape variables, and ranked models with AICc. In the eastern study region, developed land cover was positively associated with nighthawk presence and cropland showed a weak negative trend with nighthawk presence. Nighthawks in the western region showed a positive association with cropland; suggesting that cropland has a positive effect on nighthawk occurrence, presumably by providing foraging opportunities, if grassland is present within the landscape at sufficient levels. If 2006-2015 regional conversion rates of grasslands and gravel rooftops continue, Markov models project suitable breeding habitat will decrease to levels where nighthawks might be extirpated as breeding birds from urban regions of the Western Corn Belt by 2026 and with substantial population reductions over the entire Northern Prairie region by 2106.