This contrasts not only with the lesser Sooty but with all other Tyto Owls, which take most of their prey on the ground. The huge eyes of both sooty Owls compared with other Tyto Owls suggests a greater reliance on vision. Sugar Gliders and Ringtail Possums make up a high proportion of the prey but a wide variety of other mammals have been recorded. There are no records of hunting methods. The male does all the hunting during breeding and usually brings one large prey item per night.
Males often become more noisy at the start of the season, giving frequent 'bomb whistles'.
The male feeds the female in the hollow, engaging her with soft, high-pitched trilling before passing over the prey. There are a few records of nesting in caves. Females occupy the hollow for many weeks before laying, flying out only briefly during night. A female in a cave nest site rarely leaves at all. Incubation is around 42 days.