Native bird diversity is compromised in urban areas partially because of the lack of available habitat for some species. As urbanization continues to increase, it is important to understand the behavioral dynamics of bird species located in cities. The Black-capped Chickadee (Poecile atricapillus), as a generalist species, offers an opportunity to investigate how common native birds use urban areas that lack natural habitat features while additionally competing with non-native, invasive species (e.g., House Sparrows, Passer domesticus). Our objectives were to determine nest box use and nesting success rate of Black-capped Chickadees and House Sparrows using artificial nest boxes in natural habitats located in an urban area, specifically a recently restored 5.66- ha area of pond sedge surrounded by oak (Quercus spp.) savannah located south of Lincoln Park Zoo in Chicago, Illinois, USA. Artificial nest cavities with 3 cm diameter entrance holes, intended to exclude House Sparrows, were installed on trees around the study site and monitored for activity. We found that Black-capped Chickadees will readily use artificial cavities; seven of the 20 boxes were excavated and four produced nests. The artificial nesting cavities successfully excluded House Sparrows from nest building and raising young.