It is generally nocturnal, though sometimes it is active at dawn and dusk, retiring to roost in secluded spots in the foliage of trees.

The Australian boobook feeds on insects and small vertebrates, hunting by pouncing on them from tree perches.

Breeding takes place from late winter to early summer, using tree hollows as nesting sites.

The International Union for Conservation of Nature has assessed the Australian boobook as being of least concern on account of its large range and apparently stable population.

[14] William Dawes recorded the name bōkbōk "an owl" in 1790 or 1791,[15] in his transcription of the Dharug language,[7] and English explorer George Caley had recorded the native name as buck-buck during the earliest days of the colony, reporting that early settlers had called it cuckoo owl as its call was reminiscent of the common cuckoo.

He added, "The settlers in New South Wales are led away by the idea that everything is the reverse in that country to what it is in England; and the Cuckoo, as they call this bird, singing by night, is one of the instances they point out."

[17] Dutch naturalist Gerlof Mees and German evolutionary biologist Ernst Mayr regarded the taxonomy of the boobook owl complex as extremely challenging,[18] the latter remarking in 1943 that it was "one of the most difficult problems I have ever encountered".

[18] In his 1968 book Nightwatchmen of the Bush and Plain, Australian naturalist David Fleay observed that the boobooks from Tasmania more closely resembled those of New Zealand than those from mainland Australia, though he followed Mees in treating them as a single species.

[21] Examining both morphological and genetic (cytochrome b) characters in 2008, German biologist Michael Wink and colleagues concluded that the Australian boobook is distinct from the morepork and Tasmanian boobook (which they proposed to be raised to species status as Ninox leucopsis), and that it is instead the sister taxon to the barking owl (N.

[25] The Australian boobook has generally dark brown head and upperparts, with white markings on the scapulars and spots on the wings.

Its head lacks tufts common in other owls and has a paler facial disk,[25] with a white supercilium (eyebrow) and dark brown ear coverts and cheeks.

In drier areas, it is generally found along watercourses such as the Darling and Paroo Rivers, and Lake Eyre Basin.

It has adapted to landscapes altered by human activity and is found in farmland and suburban areas as long as some scattered trees are present.

[43] The characteristic two-note boo-book call or hoot can be heard up to 1 km (0.6 mi) away,[37] the second note generally lower in pitch than the first.

[46] The Australian boobook maintains and defends a territory in the breeding season; whether this continues for the rest of the year is unclear.

[48] Across Australia, breeding takes place from July to February, though peaks in October, and is generally earlier in more northern areas.

Boobooks may also evict other birds such as galahs (Eolophus roseicapillus) to use their hollows,[49] and have used sites abandoned by babblers, crows, and ravens.

The juvenile feathers begin growing through the down from days 7 to 10, covering the baby owls by two weeks of age.

They leave the nest 5–6 weeks after hatching, by which time they are fully feathered, with downy head and underparts and short tails.

and introduced cats and rats raid the nests for nestlings and eggs, and raptors such as the brown goshawk (Accipiter fasciatus), grey goshawk (Accipiter novaehollandiae), Australian masked owl (Tyto novaehollandiae), and probably powerful owl (Ninox strenua) seize young birds.

Juvenile Australian boobooks are at greater risk after bushfires and have perished after being tangled up in dodder (Cassytha) or bidgee-widgee (Acaena novae-zelandiae).

[40] The Australian boobook generally preys on mice, insects, particularly nocturnal beetles and moths, and birds the size of a house sparrow (Passer domesticus).

Birds including common starling (Sturnus vulgaris), house sparrow, red-browed finch (Neochmia temporalis), common myna (Acridotheres tristis), red-rumped parrot (Psephotus haematonotus), and white-browed babbler (Pomatostomus superciliosus), and invertebrates including grasshoppers, crickets, beetles, cockroaches, moths, wolf spiders, and huntsman spiders were also consumed.

[52] A study in Victoria found that larger animals were eaten, including Baillon's crake (Porzana pusilla), common ringtail possum (Pseudocheirus peregrinus) and feral rabbit (Oryctolagus cuniculus).

[53] Using a fence, branch, or telegraph pole as a perch or vantage point from which to hunt,[25] the Australian boobook pounces on prey then retreats to a tree or elevated place to eat it.

It often hunts in open areas near trees, and also where prey is likely to congregate, such as mice near haystacks or barns, or flying insects near street- or house-lights.

There, Australian boobook owls are dying after eating the rodents people have killed with second-generation anticoagulant rat poison.