The obvious answer might seem like House Sparrow since these two have the striped backs and black faces that distinguish that species. But there's also something different: a fully rufous (instead of gray) crown, a white collar, and a black cheek-patch. These are actually EURASIAN TREE SPARROWS, also introduced, but much more limited in both range and population than House Sparrows. They're mainly found a few midwestern states in and around St. Louis