Page "Northern Hawk-Owl" Paragraph 4

S. ulula has a variety of calls used by the different sexes in different situations.

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.