It was first described by John Gould (as Strix castanops), who wrote about it in his Handbook to the Birds of Australia as: "…a species distinguished from all the other members of its genus by its great size and powerful form.

Strictly nocturnal in its habits, as night approaches it sallies forth from the hollows of the large gum-trees, and flaps slowly and noiselessly over the plains and swamps in search of its prey, which consists of rats and small quadrupeds generally.

They have broad, black-bordered, buff to chestnut facial discs, and fully feathered legs with powerful feet and long talons.

[5] The owl has also been successfully introduced to Lord Howe Island, a subtropical territory of New South Wales in the Tasman Sea between Australia and New Zealand, where it is considered an invasive species.

They roost during the day, usually in trees in dense foliage or hollows, as well as in rocky overhangs and caves, and occasionally in farm sheds and other open buildings.

[7] These owls hunt at night, preying on a wide range of animals, from insects to mammals as large as rabbits, bandicoots and brushtail possums.

Their main diet includes introduced rodents and rabbits in agricultural areas, and marsupials and native birds in less disturbed habitats.

[8] Between December 1922 and October 1930 almost 100 masked owls, mostly from Tasmania, were introduced to Lord Howe Island in an unsuccessful attempt to control black rats.