My friend and I are stumped- we can't figure out what bird this is! I was hiking near Buttermilk Falls in Columbia, NJ and I saw what looked like a migratory bird. The size of a catbird with a more full body and a slightly pointed head like a cardinal. Dark black body and white stomach and red spots under each wing. It was flying and flew into a small tree before flying away. I was unable to get a picture. It kind of sounded like, "Sooooweet!"