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Ninox strenua
– Least Concern
Taxonomy
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Kingdom:
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ANIMALIA
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Phylum:
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CHORDATA
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Class:
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AVES
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Order:
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STRIGIFORMES
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Family:
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STRIGIDAE
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Scientific Name:
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Ninox strenua
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Species Authority:
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(Gould, 1838)
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Common Name/s:
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| English | — | POWERFUL OWL |
| French | — | NINOXE PUISSANTE |
| Spanish | — | NÍNOX ROBUSTO |
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Assessment Information
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Red List Category & Criteria:
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LC ver 3.1 (2001)
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Year Assessed:
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2004
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Assessor/s:
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BirdLife International
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Evaluator/s:
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Ekstrom, J. & Butchart, S. (BirdLife International Red List Authority)
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Justification:
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Ninox strenua occurs in open forest and woodlands in eastern Australia, from south-west Victoria to at least Eungella, and possibly Bowen, Queensland. This species has a large range, with an estimated global extent of occurrence of 100,000–1,000,000 km², but extensive areas of the range are now unsuitable as a result of clearing for agriculture and pastoralism, although the species now occupies suburban Brisbane, Sydney and Melbourne. The population size has been estimated at fewer than 500 pairs in Victoria, 1,000–1,500 pairs in north-east New South Wales, and 125 pairs in 3,200 km² of public forest and national park in south-east New South Wales (Garnett and Crowley 2000), but the species is not believed to approach the thresholds for the population size criterion of the IUCN Red List (i.e., less than 10,000 mature individuals in conjunction with appropriate decline rates and subpopulation qualifiers), even though the species is described as 'rare' in at least parts of its range (del Hoyo et al. 1999). There is some evidence of a population decline (del Hoyo et al. 1999), but recently range and numbers were considered stable, with densities in remaining habitat probably similar to pre-European levels (Garnett and Crowley 2000), and so the species is not believed to approach the thresholds for the population decline criterion of the IUCN Red List (i.e., declining more than 30% in ten years or three generations). Although densities in remaining forest may eventually be affected by a reduction in the availability of suitable nest hollows and den sites as a result of intensive forestry practices, studies indicate birds persist in mosaics of unlogged forest, in which they nest, and logged forest, in which they forage. There was no difference in density between heavily logged, lightly logged and unlogged forest. Intense wildfire can result in local loss but, if suitable habitat remains nearby, they may return to forage. Poisoning, disturbance and predation by foxes may also cause nest failure and some mortality, but are unlikely to be significant (Garnett and Crowley 2000). For these reasons, the species is evaluated as Least Concern.
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History:
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| 1988 | - | Lower Risk/least concern (BirdLife International 2004) |
| 1994 | - | Vulnerable (Collar, Crosby and Stattersfield 1994) |
| 2000 | - | Lower Risk/least concern (BirdLife International 2000) |
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Geographic Range
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Range Description:
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Ninox strenua occurs in open forest and woodlands in eastern Australia, from south-west Victoria to at least Eungella, and possibly Bowen, Queensland. This species has a large range, with an estimated global Extent of Occurrence of 100,000-1,000,000 km, but extensive areas of the range are now unsuitable as a result of clearing for agriculture and pastoralism, although the species now occupies suburban Brisbane, Sydney and Melbourne. The population size has been estimated at fewer than 500 pairs in Victoria, 1,000-1,500 pairs in north-east New South Wales, and 125 pairs in 3,200 km of public forest and national park in south-east New South Wales (Garnett and Crowley 2000), but the species is not believed to approach the thresholds for the population size criterion of the IUCN Red List (i.e. less than 10,000 mature individuals in conjunction with appropriate decline rates and subpopulation qualifiers), even though the species is described as 'rare' in at least parts of its range (del Hoyo et al. 1999). There is some evidence of a population decline (del Hoyo et al. 1999), but recently range and numbers were considered stable, with densities in remaining habitat probably similar to pre-European levels (Garnett and Crowley 2000), and so the species is not believed to approach the thresholds for the population decline criterion of the IUCN Red List (i.e. declining more than 30% in ten years or three generations). Although densities in remaining forest may eventually be affected by a reduction in the availability of suitable nest hollows and den sites as a result of intensive forestry practices, studies indicate birds persist in mosaics of unlogged forest, in which they nest, and logged forest, in which they forage. There was no difference in density between heavily logged, lightly logged and unlogged forest. Intense wildfire can result in local loss but, if suitable habitat remains nearby, they may return to forage. Poisoning, disturbance and predation by foxes may also cause nest failure and some mortality, but are unlikely to be significant (Garnett and Crowley 2000). For these reasons, the species is evaluated as Least Concern.
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Countries:
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Native:
Australia
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Habitat and Ecology
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