The Australian Owls.
Video Transcript
Never Doubt Nature
What makes an owl, an owl?
Owls are, first and foremost, raptors. That means they're birds of prey, with sharp talons, curved bills, a flat face and forward-facing eyes, all built to hunt and eat other animals. Owls stand upright, and their facial discs help focus sound inward toward their asymmetrical ears. Female owls are generally bigger than males, and most young owls look strikingly different from their parents, covered in a warm layer of white or cream down feathers that protects them in the nest.
Because owls are smaller raptors, they hunt small mammals such as rats, mice and marsupial mice. Larger species, like the powerful and rufous owls, will also take possums, gliders and rabbits. Insects, amphibians and small reptiles are hunted too. Owls tear their prey apart or eat it whole, then several hours later they regurgitate the non-edible, non-nutritious parts as a pellet. Finding pellets on the ground beneath a roost is a telltale sign that owls regularly live in the area.
Owls are found on every continent except Antarctica. There are nine species of Australian owl, plus one New Zealand owl and one owl-like bird in this video, so eleven all up. They live in a wide range of habitats. Most owls are nocturnal, solitary and shy, with excellent hearing and eyesight. They can turn their heads up to 270 degrees, and their feathers allow them to fly without making a sound. Owls are exceptionally built for stealth.
Across Australia, many owl species are doing well, but some are really struggling. The threats they face include habitat loss, secondary poisoning, being hit by cars, and being hunted by invasive species. Secondary poisoning happens because mice are often baited for pest control in agricultural and farming settings, and the owls that hunt those poisoned mice are affected in turn. This is known as secondary baiting.
Most owls also need tall, hollow trees to raise their young, and these hollows take hundreds of years to form. Many other animals rely on tree hollows too, so it's vital that we protect these trees and the old-growth forests they grow in.
Two groups of owls are found in Australia: the Tyto owls and the Ninox owls, which are the hawk owls. Hawk owls lack the heart-shaped face of the Tyto owls, such as the easily recognisable barn owl.
A fun fact: NINOX is also the name of an Australian Army project that developed night-vision goggles. It's named after Ninox strenua, the powerful owl.
So let's break down the Australian owls.
Lesser sooty owl (Tyto multipunctata)
There is a northern subspecies of the lesser sooty owl, which is paler.
These owls are quite rare and elusive. They prefer low light and aren't often seen, because they live in low-light, tropical, wet rainforests and steep gullies. Sooty owls are shy, stealthy hunters. They are strictly nocturnal and dislike even dim light. During the day they hide in dense forest foliage, in tangled rainforest and aerial roots, or in crevices. When they do come out at night, they prefer to hunt in clearings or beside dark roads.
Lesser sooty owls are found only along the wet, tropical Queensland coast. They prefer dense, lush rainforest, wet eucalypt forest and woodland, anywhere with darkness or low light, because they use sound to hunt.
They are small to medium-sized owls, 31 to 38 centimetres (12 to 15 inches) long.
They're a very striking bird, if you can spot one. Sooty owls have large black eyes and a dark grey face mask, with a lighter grey around the mask's edges and a dark, sooty outline around the rim. The head and back turn a sooty grey, and the back and wings are dark grey with white specks. The rest of the feathers range from light to dark grey, speckled with black dots, which makes them almost invisible in dappled light, darkness and shadow. The lesser sooty owl is a much paler grey than the greater sooty owl, which is up next.
Their call is a high-pitched "falling bomb" whistle, along with insect-like trills and squeaks. It's an eerie, haunting call.
The lesser sooty owl's diet mostly consists of small mammals such as rodents, bandicoots and squirrel gliders. They will also hunt small birds and large insects.
Greater sooty owl (Tyto tenebricosa)
There are at least two subspecies of the greater sooty owl. Along with the lesser sooty owl, they were all once thought to be a single species, but we now recognise more distinct species and subspecies.
The greater sooty owl is very similar in behaviour to the lesser. They are elusive and hard to spot, preferring low-light environments. They are territorial, stealthy hunters, roosting in thick foliage during the day and coming out at night to hunt in clearings or deep gullies. Unlike the lesser sooty owl, which is found only in the warm Queensland tropics, they can be found in colder climates.
Greater sooty owls are found along the eastern coast of Australia, in both coastal and mountainous regions. They are also found on Flinders Island in Bass Strait, between the mainland and Tasmania, and in New Guinea.
They prefer deep, wet gullies in eucalypt forests, with old smooth-barked eucalypts, tree ferns and a wet understorey. They roost and breed in moist areas.
Greater sooty owls are medium to large owls, 37 to 51 centimetres (15 to 20 inches) long, and the females are the larger of the pair.
They are darker and larger than the lesser sooty owl. Their back and feathers are dark grey to black, with fine white spots throughout. Females are lighter than males. The facial disc ranges from dark grey to silvery cream or sooty black, with a black, sooty edge and big black eyes. Their underparts are a lighter grey. They have a short tail and feathered legs.
Similar to the lesser sooty owl, the greater sooty owl has a descending "bomb whistle" screech, and the call can last a few seconds.
The greater sooty owl hunts arboreal, or tree-dwelling, animals such as gliders and ring-tailed possums. They will also go after rodents and bandicoots, and may hunt a variety of birds and insects.
Australian masked owl (Tyto novaehollandiae)
There is a Tasmanian subspecies of the Australian masked owl, which is endangered, and there may be up to six other subspecies. Their plumage can vary widely between individuals, from pale to intermediate to dark.
Australian masked owls prefer to live alone or in pairs. They hunt in total darkness, on the edges of forest and woodland, and may also hunt in human-modified landscapes such as farms, rural towns and parks. They are territorial, with a home range of around 1,000 hectares. They nest in large, old hollows and can be spotted near gullies and watercourses.
The Australian masked owl is found across mainland Australia. They inhabit forests and woodland near coastal and freshwater waterways, and prefer to hunt on the fringes of open country.
These are large owls, 40 to 50 centimetres (15 to 19 inches) tall, with a wingspan of 129 centimetres (50 inches).
Australian masked owls can look quite similar to a barn owl or a grass owl, with the characteristic creamy, heart-shaped face mask. Some individuals have a cream to chestnut mask, always with a dark grey outline. Their underparts range from rufous brown to creamy white, speckled with dark and lighter brown. The tops of the wings are darker, and the outer wings and back vary from black-grey to light brown and even grey-white, speckled heavily with those same colours in varying degrees.
They have a deep, rasping, screechy call and a strong, harsh hiss.
Australian masked owls hunt small reptiles and amphibians, birds, insects and many smaller mammals such as rabbits, bandicoots and rodents, and less often possums. They are often spotted near farmland, hunting rodents and rabbits.
Eastern barn owl (Tyto javanica, also classified as Tyto delicatula)
Like the sooty owls, barn owls have quite a few different populations that have been divided into various species and subspecies, such as the western barn owl, the eastern barn owl and the American barn owl.
Eastern barn owls are great, patient hunters. You can find them slowly and silently soaring over the edges of forests, roadsides and open land, listening intently for the slightest movement. Then they swoop, snatching up their prey with long legs and strong claws. They nest in tree hollows, rock clefts and caves, in the cavities of buildings, or on the ground among tussock grass.
The eastern barn owl is found throughout parts of India and South East Asia, Indonesia, New Guinea, Fiji, Tonga, Samoa, New Zealand and Australia.
They prefer open, woody country: grassland, farmland, parks, open fields, and even coastal woodland or tropical plantations. They don't mind people, and are often found in the vicinity of towns and villages.
Eastern barn owls are medium-sized owls, 30 to 40 centimetres (11 to 15 inches) in length, with a wingspan of 75 to 100 centimetres (29 to 39 inches).
They look similar to the Australian masked owl, but the eastern barn owl is a more contrasting white, with fewer speckles and vertical barring in rust-brown to dark brown-tan plumage. They are the palest of the Australian Tyto owls. They have the characteristic white, heart-shaped mask with light brown edging. The top of the head and wings are usually a dark cream or pale brown, while the rest of the body is light cream with some scattered brown speckles and a pale, white chest.
Eastern barn owls have a screechy call, just like other Tyto owls, with occasional hissing. They are one of the quieter owls and don't call often. They're most likely to call during the breeding season, or when they feel threatened.
They prey mostly on small rodents and other small, ground-dwelling animals, including mammals, reptiles and amphibians. They sometimes take bats, birds and arthropods too, including insects, spiders, scorpions and crustaceans.
Eastern grass owl (Tyto longimembris)
There are at least five subspecies of the eastern grass owl, but some are extinct.
Eastern grass owls are rarely seen because they are very shy. Their mottled plumage makes them excellent at camouflaging into their grassy home, where they almost exclusively hunt small rodents. Unlike many other owls, the eastern grass owl makes its nest on the ground, among tall grasses. They are nocturnal.
Eastern grass owls are found from India to Vietnam, south-east China, northern Malaysia, the Philippines, New Guinea, Australia, New Caledonia and Fiji.
As the name suggests, these owls live in tall grasslands and swampy areas. They prefer tropical grasslands with bladed grass, sedges or cane grasses.
Eastern grass owls are medium-sized owls, measuring 32 to 40 centimetres (13 to 18 inches), with a wingspan of 100 to 115 centimetres (39 to 45 inches). Although they resemble barn owls, they have a much longer wingspan.
They strongly resemble barn owls, with more tan-brown colouring. Black-brown, bronze and tan bars run down their backs and wings, while the rest of their body is a lighter tan or creamy white. They have a prominent, white, heart-shaped facial disc, framed by cream and brown on the top of the head. Their colouring helps them blend in exceptionally well with their grassy habitat, and their longer legs and wings suit them to life in long grass.
Similar to other Tyto owls, eastern grass owls have a harsh, screeching call.
They are one of the more specialised owls when it comes to diet. They rarely take prey other than rodents and small marsupials, though they eat a large variety of both. They hunt almost entirely on the wing, rather than from a perch like other owls and raptors may, using their excellent hearing and their long legs, which reach down over the grass, to detect prey.
Southern boobook (Ninox boobook)
There are Papua New Guinean, Indonesian and Christmas Island subspecies of the boobook owl, as well as a Tasmanian boobook. There's also the morepork, a very similar species found in New Zealand. We'll hear more about that bird soon.
The southern boobook hides in dense foliage during the day. They have several roosting spots within their territory, and may move between them throughout the day, but they are most active at night or twilight. They may roost in caves, trees or on ledges. At night, boobooks perch on a branch, fence, ledge or telephone pole where they have a good vantage point, then listen and watch for movement, and pounce.
The southern boobook is found in all Australian states and territories. They live in wooded habitats such as forests, farmland, and urban and suburban parks, as long as there are mature trees.
They are the smallest of the Australian owls, and the smallest of the hawk owls, at 27 to 36 centimetres (10 to 14 inches) tall, with a wingspan of 60 to 90 centimetres (about 24 to 35 inches).
Boobooks are dark brown to grey with white streaks or spots across their body and under their wings. Some birds have paler or stronger white streaks or spots, depending on the area. The undersides are a lighter brown than the head and back. Plumage colour and size vary slightly depending on habitat. They have large, yellow-green eyes and distinctive brown patches behind the eyes, sometimes called "glasses" or a "half mask".
Boobook owls have a distinctive double-note call: "boo-book", with the second note lower in pitch than the first. You're most likely to hear a boobook before you ever see one.
Their diet consists mostly of mice, small sparrow-like birds, small bats, spiders and insects, especially nocturnal beetles and moths.
Morepork (Ninox novaeseelandiae)
The morepork is a type of boobook owl, called "ruru" throughout New Zealand. The name comes from its two-toned call. I always thought it was called a "mopoke". I guess it just depends on what those around you said!
There are at least four subspecies of morepork. Two of these are extinct, and one survives only as a hybrid population. The New Zealand birds are the dominant morepork, and another subspecies is referred to as the Australian boobook.
The compact morepork is a small, forest-dwelling owl that can fly incredibly well through dense forest. They can be territorial, and are most often seen in headlights or streetlights, where they hunt moths, but that also makes them easy to hit with a car or fall prey to predators. If you hear moreporks calling in a duet, it's most likely rivals duelling rather than joining in song.
Moreporks are found in New Zealand and its offshore islands. They're very similar to the Australian boobook, and in fact any Australian reference to a "morepork" usually means the boobook, which has many nicknames.
The morepork measures around 29 centimetres (11.4 inches), with a wingspan of 50 centimetres (19 inches).
Their plumage ranges from dark brown to light brown with off-white spots or streaks, which are sparser on the back. The chest is lighter, with darker brown hues on the back and wings. The legs are feathered right down to their yellow toes. Moreporks have a more spotted appearance than southern boobooks, with brighter yellow eyes.
The morepork's call sounds just like its name: "more pork", "ru ru", or "boo-book".
Moreporks feed mainly on insects and small vertebrates, including beetles, moths, caterpillars and worms, spiders, grasshoppers, and the New Zealand weta, a huge, flightless cricket weighing around 70 grams (2.5 ounces). They may also eat small birds, such as silvereyes and other small songbirds, and rodents.
Powerful owl (Ninox strenua)
Powerful owls are active only at night, and prefer to roost during the day in a big, shady tree. At night, they hunt large, tree-dwelling mammals such as possums and gliders. These owls are being found in human habitats more and more, following their prey, with possums such as ringtails appearing in inner-city parks and gardens. Powerful owls mate for life.
The powerful owl is found only in eastern and south-eastern Australia, from south-eastern Queensland to Victoria.
They prefer open forests, and can be found along sheltered gullies with dense understoreys in wet forests, or near a watercourse. They can also be found on farmland, near parks, in remnant bushland and in suburban areas. Like most owls, they need old hollows for nesting.
Powerful owls are Australia's largest owls, measuring between 60 and 67 centimetres (about 24 to 26 inches), with a wingspan of up to 140 centimetres (approximately 55 inches).
They have a small head, a large body and a rounded tail. Their colouring is dark grey to dark grey-brown with white barring, and an off-white underside marked with dark, V-shaped chevrons on the feathers. They have big yellow eyes set in a dark grey-brown facial disc, and huge, strong yellow-orange feet with sharp talons and feathered legs.
Powerful owls have a deep, slow double hoot, with the second note higher pitched than the first. Females are higher pitched than males, and pairs also call in duets.
Powerful owls go after much larger prey than most owls. They will readily hunt possums, flying foxes and bats, small roosting birds, small to medium reptiles and amphibians, and land-dwelling mammals such as smaller kangaroos, wallabies, rabbits and rodents. In the trees, they prefer brushtail and ringtail possums and greater gliders, and they may also go after rabbits on the ground.
Rufous owl (Ninox rufa)
There are four subspecies of rufous owl. One is found in New Guinea, some Papuan islands and the Aru Islands, and the others are found in various areas across north-east coastal Queensland, Australia.
Rufous owls prefer to roost high up in dense foliage during the day, and are found only in tropical rainforests. They rarely call. The only time they do is during breeding season, to communicate with their mate in various pitches. They are powerful hunters, with a wide variety of prey.
The rufous owl is found in the Aru Islands off Indonesia, in New Guinea, and in the tropical north of Australia. They prefer tropical climates, and are found in rainforest and sclerophyll forest, often lining watercourses or mangrove forests.
Rufous owls are rarely seen, but they're classified as a large owl at 46 to 57 centimetres (18 to 22 inches), with a wingspan of 100 to 120 centimetres (39 to 47 inches). If they are seen, they're usually roosting alone, in pairs or in family groups, on a bare horizontal branch.
They are dark brown to reddish brown with thin, horizontal barring in off-white or light brown, which is stronger on the underparts. They have greenish-yellow eyes and a prominent brown masked face and head.
Rufous owls have a typical owl call of "hoo", a long, low double hoot.
Rufous owls prefer to catch prey on the wing, eating small to medium-sized animals. They glide through the forest and snatch prey from roosts or perches. They will hunt fruit bats in flight, along with small to medium birds and large insects. They also eat small to medium mammals such as possums, taken from branches, and may even keep the kill from a previous night in their roost, to pick at throughout the day.
Barking owl (Ninox connivens)
There are two subspecies of barking owl. One is found in eastern and southern Australia, and the other in far north Queensland and the Northern Territory.
Barking owls are often heard before they are seen, and their call is often confused with a barking dog. They spend their days roosting high and hidden in foliage, then emerge to hunt or survey from lone branches. They take prey in flight, near the ground, water or trees, or from the air, and will happily hunt in open or densely forested areas. They are usually found in pairs and mate for life.
The barking owl is found in Australia, Papua New Guinea and the Maluku Islands in Indonesian waters.
They prefer forested areas, often near rivers, swamps or creeks. They may also nest in farm rafters, streets and suburban areas.
Barking owls are a medium-sized bird, about 37 to 43 centimetres (14.5 to 16 inches) long, with a wingspan of roughly 85 to 98 centimetres (33 to 38 inches). They have a dark grey to brown back streaked with white spots, and white undersides streaked with thick, brown vertical stripes. The head feathers are grey-brown.
Barking owls are named for their barking call, like a dog barking in the distance. They also have a trilling call and a nocturnal flight call.
Barking owls prefer to hunt in the hours before dawn and after dusk, but will also hunt during the day. They prefer small mammals such as rodents and rabbits, small birds, reptiles, amphibians, and a variety of insects and spiders. They prefer bigger game during the breeding season, and feast on insects all year round.
Tawny frogmouth: not an owl (Podargus strigoides)
The tawny frogmouth is a nightjar, not a raptor. They prefer to hunt insects, but may also take small animals such as mice and frogs.
If you've ever spotted a tawny frogmouth in a Melbourne garden at dusk, you've probably thought, "Look, an owl!" And honestly, you're in good company, because this bird has fooled people for generations. But the tawny frogmouth isn't an owl at all. It isn't even a raptor. It's a close relative of the nightjars, in a completely different order of birds.
So why do they look so alike?
The answer is something zoologists call convergent evolution. When unrelated animals face the same challenge, nature can arrive at remarkably similar solutions. And for owls and frogmouths, that challenge is surviving the night and the day.
Starting with the face, both owls and tawnies have big, forward-facing eyes, built to gather every scrap of light after dark. Both have soft, mottled plumage that lets them camouflage against bark and branches. And both are masters of the ambush: they sit perfectly still on a perch, wait, then drop silently onto insects, small mammals, frogs and lizards.
When a frogmouth senses danger, it freezes, stretches its body upright and points its beak to the sky, looking exactly like a broken branch. It can even watch you through tiny slits in its eyelids while its eyes appear closed. Owls also rely on stillness and cryptic feathers to avoid being spotted by predators and mobbing birds.
But look at the feet and beak, and the difference becomes clear. Owls are raptors, armed with powerful talons. The frogmouth has weak feet and instead uses its enormous, wide beak, which is where the name comes from, to snap up prey.
So: same night shift, same disguise, completely different family tree.
