The Rajah scops owl (''Otus brookii'') is a species of

owl Owls are birds from the order Strigiformes (), which includes over 200 species of mostly solitary and nocturnal birds of prey typified by an upright stance, a large, broad head, binocular vision, binaural hearing, sharp talons, and feathers a ...

found on the islands of

Borneo Borneo () is the List of islands by area, third-largest island in the world, with an area of , and population of 23,053,723 (2020 national censuses). Situated at the geographic centre of Maritime Southeast Asia, it is one of the Greater Sunda ...

and

Sumatra Sumatra () is one of the Sunda Islands of western Indonesia. It is the largest island that is fully within Indonesian territory, as well as the list of islands by area, sixth-largest island in the world at 482,286.55 km2 (182,812 mi. ...

. The bird is named after

James Brooke James Brooke (29 April 1803 – 11 June 1868), was a British soldier and adventurer who founded the Raj of Sarawak in Borneo. He ruled as the first White Rajahs, White Rajah of Sarawak from 1841 until his death in 1868. Brooke was born and ra ...

, Rajah of Sarawak. Based on patterns of speciation in other endemic montane bird species of the same region, it may potentially have to be split into two distinct species; if so, the name ''Otus brookii'' would be restricted to just the Bornean population.

Taxonomy

There are two

subspecies In Taxonomy (biology), biological classification, subspecies (: subspecies) is a rank below species, used for populations that live in different areas and vary in size, shape, or other physical characteristics (Morphology (biology), morpholog ...

known from two different islands: ''O. b. brookii'' (the type subspecies) found on

and ''O. b. solokensis'' found on

. Taking into account speciation patterns within ''

Otus Otus may refer to: * Otus (education), a K-12 educational technology company * HMS ''Otus'', two ships in the Royal Navy * ''Otus'' (bird), genus of owls * Otus (mythology), giant in Greek mythology, brother of Ephialtes, one of Aloadae * Otus o ...

'' and general phylogeographic patterns of montane birds on Borneo and Sumatra, both subspecies likely represent two distinct species; taxonomic studies will be required to confirm or deny this claim.

Distribution

''O. b. solokensis'' has a comparatively large range, being distributed throughout the length of the

Barisan Mountains The Bukit Barisan or the Barisan Mountains are a mountain range on the western side of Sumatra, Indonesia, covering nearly 1,700 km (1,050 mi) from the north to the south of the island. The Bukit Barisan range consists primarily of volca ...

. In contrast, ''O. b. brookii'' was formerly only known to have a comparatively small range in the mountains straddling the border of

Kalimantan Kalimantan (; ) is the Indonesian portion of the island of Borneo. It constitutes 73% of the island's area, and consists of the provinces of Central Kalimantan, East Kalimantan, North Kalimantan, South Kalimantan, and West Kalimantan. The non-Ind ...

and

Sarawak Sarawak ( , ) is a States and federal territories of Malaysia, state of Malaysia. It is the largest among the 13 states, with an area almost equal to that of Peninsular Malaysia. Sarawak is located in East Malaysia in northwest Borneo, and is ...

, with a small extension into

Sabah Sabah () is a States and federal territories of Malaysia, state of Malaysia located in northern Borneo, in the region of East Malaysia. Sabah has land borders with the Malaysian state of Sarawak to the southwest and Indonesia's North Kalima ...

. Due to its secretive nature, it had not been sighted since its description by

Richard Bowdler Sharpe Richard Bowdler Sharpe (22 November 1847 – 25 December 1909) was an English people, English zoologist and ornithology, ornithologist who worked as curator of the bird collection at the British Museum of natural history. In the course of his car ...

in 1892. In May 2016, an individual was observed and photographed on the slopes of

Mount Kinabalu Mount Kinabalu ( Dusun: ''Gayo Ngaran'' or ''Nulu Nabalu'', ) is the highest mountain in Malaysia and Borneo. With a height of , it is the third-highest peak of an island on Earth, the 28th highest peak in Southeast Asia, and 20th most prom ...

, well away from the range it was formerly assumed to have, marking a new range extension for the subspecies. This was the first sighting of it in over 125 years, and the first-ever photograph of it in the wild. Sightings were again reported in 2021.

Description

Adults have a fierce-looking face. The body overall is dark brown. When perched, the blackish crown and white ear-tufts are visible. Its underparts are brownish with thick black streaking. It has a distinct orange iris. The subspecies ''Otus brookii solokensis'' is different in plumage from ''O. b. brookii'' in having darker underparts, thicker streaking a less distinct nuchal collar. Juveniles of ''O. b. brookii'' remain undescribed. ''O. b.solokensis'' has rufous upperparts and vermiculations on the underparts.

Vocalizations

''O.b.solokensis'' has an explosive "owh" or "owh-owh" barking call lasting about a half-second and repeated irregularly.

Habitat

It is uncommon in

montane forest Montane ecosystems are found on the slopes of mountains. The alpine climate in these regions strongly affects the ecosystem because temperatures lapse rate, fall as elevation increases, causing the ecosystem to stratify. This stratification is ...

s above an altitude of . It can be found perched in the lower canopy.

References

BirdLife Species Factsheet
*http://www.owlpages.com/owls.php?genus=Otus&species=brookii Otus (bird) Birds of Sumatra Birds of Borneo Owls of Asia Birds described in 1892 Fauna of the Borneo montane rain forests {{Strigiformes-stub