Just a few miles from the nation's capital the Patuxent Research Refuge is the largest remaining area of natural habitat in the intensely developed Baltimore-Washington DC corridor. The refuge was established in 1936 on former farmland and has since been used primarily for research into wildlife and habitat management. Approximately 75% of the site is forested, with pine, hardwood and mixed forests on uplands and swamp forest of oak, maple and sweetgum on the floodplains of the Patuxent and Little Patuxent Rivers. Other habitats include grassland, early successional habitats, ponds and lakes. The refuge is owned and managed by the US Fish and Wildlife Service as part of the National Wildlife Refuge System.
The birds of Patuxent Research Refuge have been extensively documented by several refuge-wide surveys. The site supports one of the most diverse communities of Forest-Interior Dwelling Species on Maryland?s coastal plain with 20 species regularly breeding, although population densities of some of these has declined due to overbrowsing by deer of the forest shrub layer. Three species on the WatchList (Yellow category), Wood Thrush, Kentucky Warbler and Prairie Warbler, have significant populations here. Surveys conducted annually in the breeding season have detected 30-55 Whip-poor-wills and upto 10 American Woodcocks in years since 2000. This site supports the largest population of Whip-poor-will?s in central Maryland.