It is one of the few owls that is not nocturnal or crepuscular. This is the only living species in the genus Surnia of the family Strigidae, the "typical" owls (as opposed to barn owls, Tytonidae). The species is sometimes called simply the Hawk Owl; however, many species of owls in the Ninox genus are also called "hawk owls".
When attracting a mate the male usually lets out a rolled whistle of ulululululululul and a sound similar to tu-wita-wit, tiwita-tu-wita, wita, when perching at a potential nest site.
The female’s call is usually less constant and more shrill.
The Northern Hawk-Owl is a partially diurnal hunter, although it has been recorded hunting at varying times and does not appear to have a preferred hunting time