Northern masked owl | |
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At Groote Eylandt, off the coast of Australia's Northern Territory | |
Scientific classification | |
Domain: | Eukaryota |
Kingdom: | Animalia |
Phylum: | Chordata |
Class: | Aves |
Order: | Strigiformes |
Family: | Tytonidae |
Genus: | Tyto |
Species: | |
Subspecies: | T. n. kimberli |
Trinomial name | |
Tyto novaehollandiae kimberli | |
Tyto novaehollandiae kimberli range [2] | |
Synonyms | |
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The northern masked owl (Tyto novaehollandiae kimberli) is a large forest owl in the family Tytonidae. The northern kimberli subspecies was identified as a novel race of the Australian masked owl by the Australian ornithologist Gregory Macalister Mathews in his 1912 reference list of Australian birds. [1] The northern masked owl occurs in forest and woodland habitats in northern Australia, ranging from the northern Kimberley region to the northern mainland area of the Northern Territory and the western Gulf of Carpentaria. [2] [3] While the Australian masked owl is recognized as the largest species in the family Tytonidae (barn owls), the northern masked owl is one of the smallest of the Australian masked owl subspecies.
The northern masked owl is a subspecies of the Australian masked owl (Tyto novaehollandiae), a large tytonid owl which resembles the barn owl. [4] The Australian masked owl ranges over non-arid areas of the Australian continent, southern Papua New Guinea and a number of islands north of Papua New Guinea and in the eastern Indonesian archipelago. [5] Eight subspecies of Tyto novaehollandiae have been recognised, however there has been confusion over the status and inclusion of a number of previously described populations as independent species or subspecies. [4] [6] Species level taxa that are now considered to be subspecies of Tyto novaehollandiae include T. manusi and T. sororcula. [6] The relationships between the northern Australian subspecies and populations are unresolved. [7] [8]
In 1912 Mathews [1] [9] identified eight subspecies of masked owl in Australia, including T. n. castanops, T. n. kimberli, T. n. melvillensis, T. n. mackayi, T. n. novaehollandiae, T. n. perplexa, T. n. riordani and T. n. whitei, based on observations of distribution, morphology and plumage. Two additional races were subsequently described, including T. n. galei (Mathews 1914) from Cape York Peninsula [10] and T. n. troughtoni (Cayley 1931) from the Nullarbor plain region of South Australia/Western Australia. [11] Recent taxonomic revisions recognise only four of these subspecies as occurring in Australia, including T. n. novaehollandiae (eastern and southern mainland, southwest Western Australia), T. n. castanops (Tasmania), T. n. melvillensis (Tiwi Islands) and T. n. kimberli (northern Australia including Kimberly, Top End and Cape York). [6] Four extralimital races of the Australian masked owl are also recognised, including T. n. calabyi (Mason, 1983) from southern Papua New Guinea, T. n. manusi (Rothschild & Hartert, 1914) from the Admiralty Islands group (PNG), T. n. sororcula (Sclater, 1883) from the Tanimbar Islands (Indonesia) and T. n. cayelii (Hartert, 1900) from Buru Island (Indonesia). [4]
Australian masked owls from Cape York Peninsula have been separated as the subspecies T. n. galei by some authors, [12] however some authorities include this population with T. n. kimberli. [4] The central Queensland subspecies T. n. mackayi (Mathews 1912) may also considered to be synonymous with T. n. kimberli. [13] The Action Plan for Australian Birds 2020 treats Tyto novaehollandiae kimberli as separate from the Cape York and wet tropics race T. n. galei, however the relationship between these subspecies requires further investigation. [3] [8]
Mathews [1] described the northern masked owl as being smaller and paler than the nominate race of the Australian masked owl (T. novaehollandiae novaeholladiae). Subsequent observations have confirmed that the northern masked owl is small in size when compared to other Australian masked owl races, with the exception of the Tiwi masked owl (Tyto novaehollandiae melvillensis). Based on data recorded on museum specimen labels and reported in the Handbook of Australian and New Zealand Birds, female northern masked owls weigh approximately 700 g (25 oz) and males approximately 450 g (16 oz). This is considerably lighter than the Tasmanian masked owl, with race castanops females weighing up to 1,260 g (44 oz) and males weighing up to 800 g (28 oz). [4]
The northern masked owl is uncommon and widely dispersed across broad areas of northern Australia, with the main areas of distribution including the north-west Kimberley region of Western Australia, the northern section of the Northern Territory between the Victoria River and eastern Arnhemland, and Groote Eylandt in the east. Significant populations occur in the north-west of the Kimberley, the Northern Territory mainland between Victoria River and Kakadu National Park, Garig Gunak Barlu National Park (Coburg Peninsula) and Groote Eylandt. [2] [3] Island populations are known from Augustus and Koolan Islands in the Kimberley region of Western Australia and Groote Eylandt, Akwamburkba (Winchelsea Island) and North Goulburn Islands in the Northern Territory. The historical distribution extended to the Borroloola region in the eastern Northern Territory, but the veracity of these records is undetermined. [3] Several early historical specimens labelled from this region are held in museum collections but recent surveys in the Borroloola area and at Pungalina Station failed to detect northern masked owls. [14] In 2019 and 2020 there were confirmed northern masked owl records from Groote Eylandt, north-eastern Arnhemland, Kakadu National Park and the Mitchell Plateau and Yampi Peninsula in Western Australia. [3]
Northern masked owl predominantly forage in eucalypt open forests and woodlands with open understories and roost in closed monsoon forests and tree hollows. [3] [15] [4] [16] Foraging also occurs in more open habitats and masked owls have also been recorded in Melaleuca forests, rainforest, riparian forest, grasslands, mangroves, grassland and coastal dunes. [4] [15] In the Northern Territory, northern masked owls frequently occur in Darwin stringybark ( Eucalyptus tetrodonta ) and Darwin woollybutt ( Eucalyptus miniata ) tall open forest. [3] [15] [17] On Groote Eylandt they are mainly observed foraging in tall open forest and woodland, on the margins of sandstone escarpments and one occasion on beach dunes adjacent to open forest. [3] [17]
The south-eastern nominate race of the Australian masked owl has a home range of 5–10 km2. [18] and it is speculated that the range of the northern masked owl could cover a similar area. [15] Relatively high densities of northern masked owls have been detected on Groote Eylandt, with a home range estimate of 4–5 km2 based on sampling across several large forest grids covering approximately 5000 ha. Surveys indicate lower densities and predicted larger home range areas on Coburg peninsula and very low densities at other Northern Territory mainland range areas. [3]
Northern masked owls maintain diurnal roosts in hollows in the trunk or near-vertical spouts of large live or dead canopy trees. [4] [15] Northern masked owls also roost on branches in dense vegetation, including in monsoon vine forests and riparian vegetation on drainage lines. [4] Recently discovered roost sites in the Kimberley have all been associated with tall Melaleuca gallery (riparian) forest adjacent to sandstone escarpments and open savannah woodland.[ citation needed ]
The diet of the northern masked owl is poorly known, although is presumed to be similar to that of the southern Australian masked owl subspecies, which feed mostly on small to medium-sized terrestrial mammals and take smaller percentages of scansorial and arboreal mammals, insects and birds. [4] Stomach contents of two northern masked owl specimens from the Kimberley contained small birds and marsupials including savanna glider (Petaurus ariel). [19] Northern masked owl have been observed consuming brush-tailed rabbit-rat on Groote Eylandt. [3]
Several northern masked owl call variations have been observed in the field. The most common call is a loud, extended rasping screech that is given while perching or in flight and is possibly used in territorial defense and/or as a contact call. [4] A "chatter" call, described as a loud cackle or continuous chatter, [4] is likely to be associated with courtship display flights by male birds circling over breeding territory (based on other Australian masked owl subspecies) [4] and is sometimes given in response to call broadcast during surveys. Other social calls are poorly known but are likely to be similar to those documented for other Australian masked owl subspecies, including extended high pitched trills, rasping and stuttered hissing when approaching young in the nest or to solicit feeding, churrs and hissing during nest defence and low pitched cooing during mating and courtship. [4]
Information on the reproduction of the northern masked owl is limited. Northern masked owls lay 2–4 eggs in a large tree hollow, with clutches recorded in the Northern Territory in May, August and September. [3] [4]
The IUCN (2018) has assessed the Australian masked owl (Tyto novaehollandiae) as 'least concern' but has not provided subspecific status assessments. [20] The northern masked owl is listed as a vulnerable species under the Commonwealth EPBC Act 1999, [21] vulnerable in Queensland [22] and vulnerable in the Northern Territory. [23]
The Action Plan for Australian Birds 2020 assessed the status of the northern masked owl as vulnerable C2a(i), finding that despite the discovery of a relatively high-density population on Groote Eylandt, declining prey populations on the mainland are likely to be causing ongoing declines. The infrequency of confirmed sightings of this subspecies on the mainland suggests that there is a high level of uncertainty in terms of status and trends. [3]
The northern masked owl appears to be uncommon across most of its range, and a recent population estimate for the Northern Territory and Western Australian distribution (excluding Queensland populations) ranges from 2000 to 5000 mature individuals. There are a limited number of localities where the northern masked owl appears to remain relatively common, including Garig Gunak Barlu National Park, the north-west Kimberley and the Anindilyakwa Indigenous Protected Area (Groote Eylandt). These sites are likely to represent important refuge areas for northern masked owl populations and have potentially been less impacted by fire regime changes, disturbance from pastoralism, feral animals and decline of prey species that has been documented at other locations. [3]
Identified and potential threats to populations of the northern masked owl are related to the direct and indirect actions of humans ( Homo sapiens ), including land clearing, altered fire regimes, stocking with exotic ruminants, proliferation of feral animals and weeds and atmospheric pollution leading to global heating.[ citation needed ]
The main threat to northern masked owl populations is thought to be the decline in the availability of mammalian prey [24] linked to more frequent and extensive fires and predation by feral cats, [25] exacerbated in some places by feral herbivore and cattle grazing [26] and weed encroachment. [16] The only sites where prey remain relatively abundant are Groote Eylandt [27] and the Kimberley. [28] The large trees and hollows required for nesting may be reduced in number due to the current regime of more intense and frequent fires. However, these trees continue to be abundant [29] and highly mobile species with large home range areas such as northern masked owls may be less vulnerable to local impacts of fire on key habitat resources. [30] Mining exploration licences and active mining titles cover broad areas of northern masked owl range, including most of Groote Eylandt and Winchelsea Island, and components of north-eastern Arnhemland, Batchelor/Pine Creek, Daly, north-west Kimberley and Yampi regions. [3]
The northern masked owl was ranked as having a medium level of sensitivity to the impacts of global heating in a study conducted by the Australian National Climate Change Adaptation Research Facility. [31]
The northern masked owl has been recorded in several of conservation reserves, including the Mitchell River National Park (WA), Lawley River National Park (WA), Kakadu National Park (NT), Garig Gunak Barlu National Park (Coburg Peninsula) (NT), Keep River National Park (NT), Judbarra/Gregory National Park (NT) and Nitmiluk National Park (NT). [2] [3] Northern masked owls are present in a number of private conservation reserves managed by the Australian Wildlife Conservancy, including reserves at Mornington Station, Yampi and Artesian Range/Charnley River in the Kimberley. [2]
Northern masked owls were recorded on Groote Eylandt in 2010 [17] and on Akwamburkba (Winchelsea Island) in 2018 within the Anindilyakwa Indigenous Protected Area. Northern masked owl occur in other Indigenous Protected Areas and Indigenous lands, including the Anindilyakwa, Arrabrkbi, Birriwinjku, Bunubu, Dambimangari, Gagudju, Garawa, Kundjeyhmi, Jawoyn, Kamu, Karde, Yek Diminin, Kenbi, Koonguruku, Labarganyan, Larrakia, Limilngan, Malak, Maranunggu, Mayala, Mirarr, Ngan'gi, Ngombur, Ngumbarl, Nimanburr, Rakpeppimenarti, Uunguu, Waanyi, Wagiman, Warai, Warrwa, Wilinggin, Wulna, Wunambal, Gaambera and Yammirr. [3]
Barn-owls are one of the two families of owls, the other being the true owls or typical owls, Strigidae. They are medium to large owls with large heads and characteristic heart-shaped faces. They have long, strong legs with powerful talons. They also differ from the Strigidae in structural details relating in particular to the sternum and feet.
Groote Eylandt is the largest island in the Gulf of Carpentaria and the fourth largest island in Australia. It was named by the explorer Abel Tasman in 1644 and is Dutch for "Large Island" in archaic spelling. The modern Dutch spelling is Groot Eiland.
The barn owl is the most widely distributed species of owl in the world and one of the most widespread of all species of birds, being found almost everywhere except for the polar and desert regions, Asia north of the Himalayas, most of Indonesia, and some Pacific Islands. It is also known as the common barn owl, to distinguish it from the other species in its family, Tytonidae, which forms one of the two main lineages of living owls, the other being the typical owls (Strigidae).
The masked lapwing is a large, common and conspicuous bird native to Australia, particularly the northern and eastern parts of the continent, New Zealand and New Guinea. It spends most of its time on the ground searching for food such as insects and worms, and has several distinctive calls. It is common in Australian fields and open land, and is known for its defensive swooping behaviour during the nesting season.
The Top End of Australia's Northern Territory is a geographical region encompassing the northernmost section of the Northern Territory, which aside from the Cape York Peninsula is the northernmost part of the Australian continent. It covers a rather vaguely defined area of about 245,000 km² behind the northern coast from the Northern Territory capital of Darwin across to Arnhem Land with the Indian Ocean on the west, the Arafura Sea to the north, and the Gulf of Carpentaria to the east, and with the almost waterless semi-arid interior of Australia to the south, beyond the huge Kakadu National Park.
The striated pardalote is the least colourful and most common of the four pardalote species. Other common names include pickwick, wittachew and chip-chip. It is a very small, short-tailed bird that is more often heard than seen, foraging noisily for lerps and other small creatures in the treetops.
The northern quoll, also known as the northern native cat, the North Australian native cat or the satanellus is a carnivorous marsupial native to Australia.
Threatened fauna of Australia are those species and subspecies of birds, fish, frogs, insects, mammals, molluscs, crustaceans and reptiles to be found in Australia that are in danger of becoming extinct. This list is the list proclaimed under the Australian federal Environment Protection and Biodiversity Conservation Act 1999. The classifications are based on those used by the World Conservation Union (IUCN), however IUCN and Australian rankings do differ. Each state and territory has its own legislation relating to environmental protection.
Tyto is a genus of birds consisting of true barn owls, grass owls and masked owls that collectively make up all the species within the subfamily Tytoninae of the barn owl family, Tytonidae.
The Australian boobook, is a species of owl native to mainland Australia, southern New Guinea, the island of Timor, and the Sunda Islands. Described by John Latham in 1801, it was generally considered to be the same species as the morepork of New Zealand until 1999. Its name is derived from its two-tone boo-book call. Eight subspecies of the Australian boobook are recognized, with three further subspecies being reclassified as separate species in 2019 due to their distinctive calls and genetics.
The Australian masked owl is a barn owl of Southern New Guinea and the non-desert areas of Australia.
The powerful owl, a species of owl native to south-eastern and eastern Australia, is the largest owl on the continent. It is found in coastal areas and in the Great Dividing Range, rarely more than 200 km (120 mi) inland. The IUCN Red List of Threatened Species also refers to this species as the powerful boobook. An apex predator in its narrow distribution, powerful owls are often opportunists, like most predators, but generally are dedicated to hunting arboreal mammals, in particular small to medium-sized marsupials. Such prey can comprise about three-quarters of their diet. Generally, this species lives in primary forests with tall, native trees, but can show some habitat flexibility when not nesting. The powerful owl is a typically territorial raptorial bird that maintains a large home range and has long intervals between egg-laying and hatching of clutches. Also, like many types of raptorial birds, they must survive a long stretch to independence in young owls after fledging. Unlike most raptorial birds, however, male powerful owls are larger and stronger than females, so the male takes the dominant position in the mating pair, which extends to food distribution.
The rainbow pitta is a small passerine bird in the pitta family, Pittidae, endemic to northern Australia, most closely related to the superb pitta of Manus Island. It has a velvet black head with chestnut stripes above the eyes, olive green upper parts, black underparts, a bright red belly and an olive green tail. An Australian endemic, it lives in the monsoon forests and in some drier eucalypt forests.
The red-collared lorikeet is a species of parrot found in wooded habitats in northern Australia. It was previously considered a subspecies of the rainbow lorikeet, but today most major authorities consider them as separate species. No other member of the rainbow lorikeet group has an orange-red collar over the nape.
The black-footed tree-rat, also known as Djintamoonga, is one of two endemic Australian rodent species in the genus Mesembriomys. Both the black-footed tree-rat and its congener, the golden-backed tree-rat, are found in northern Australia. The species is one of the largest murids found in Australia.
Nabarleks, are a tiny species of macropod found in northern Australia. They are a shy and nocturnal animal that resides in rocky hollows and forages in the surrounding area. Their diet is grasses, sedges, and ferns found in and around their scrub covered refuges. They are distinguished by a reddish tinge to the mostly grey fur and a distinct stripe at the cheek. They move with great speed and agility when observed, with a forward leaning posture and a bushy tail that arches over the back.
The northern rosella, formerly known as Brown's rosella or the smutty rosella, is a species of parrot native to northern Australia, ranging from the Gulf of Carpentaria and Arnhem Land to the Kimberley. It was described by Heinrich Kuhl in 1820, and two subspecies are recognised. The species is unusually coloured for a rosella, with a dark head and neck with pale cheeks—predominantly white in the subspecies from the Northern Territory and blue in the Western Australian subspecies hillii. The northern rosella's mantle and scapulars are black with fine yellow scallops, while its back, rump and underparts are pale yellow with fine black scallops. The long tail is blue-green, and the wings are black and blue-violet. The sexes have similar plumage, while females and younger birds are generally duller with occasional spots of red.
The Manus masked owl is a barn owl endemic to Manus Island in the Admiralty Islands. Some authors consider it a subspecies of Australian masked owl (Tyto novaehollandiae).
The canary white-eye or yellow white-eye is a species of white-eye endemic to northern Australia in subtropical or tropical mangrove forests. Its common name reflects the circle of white feathers around its eye.
The Tasmanian masked owl is a bird in the barn owl family Tytonidae that is endemic to the island state of Tasmania, Australia. It is the largest subspecies of the Australian masked owl, the largest Tyto owl in the world, and is sometimes considered a full species. The subspecific name castanops, meaning "chestnut-faced", comes from the colouring of the facial disc. It was first described by John Gould, 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. Probably few of the Raptorial birds, with the exception of the Eagles, are more formidable or more sanguinary in disposition."
"Forests of large but thinly scattered trees, skirting plains and open districts, constitute its natural habitat. 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."