Fraser's eagle-owl (''Bubo poensis'') is a species of African

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 ...

in the family

Strigidae The true owls or typical owls (family Strigidae) are one of the two generally accepted families of owls, the other being the barn owls (Tytonidae). This large family comprises 230 living or recently extinct species in 24 genera. The typical ow ...

. It is named after the British zoologist

Louis Fraser Louis Fraser (1819 – c. 1883) was a British zoologist and collector. In his early years, Fraser was curator of the Museum of the Zoological Society of London. Little is known about Fraser's early life. He was born in 1819 or 1820 and married Mary ...

Description

Fraser's eagle-owl is a relatively small species of eagle-owl with has rather "fluffy" ear-tufts and a facial disc with a distinct dark rim. The upperparts are rufous and buffy brown, barred with darker bars, the pale

scapulars The scapula (plural scapulae or scapulas), also known as the shoulder blade, is the bone that connects the humerus (upper arm bone) with the clavicle (collar bone). Like their connected bones, the scapulae are paired, with each scapula on either ...

have dark-edged outer webs which show as a series of pale dots across the shoulder. The flight and tail feathers have narrow light and dark bars. The underparts are pale rufous shading to whitish on the belly and undertail coverts. Total length is , with the females larger than males.

Voice

The territorial song of the male Fraser's eagle-owl is a rapid, stuttering and long deep, guttural trill which has been said to resemble the noise made by an electricity generator. There is also a two syllable hoot, which is stereotypically owl-like, with the second syllable being higher pitched and more whistled. The double hoot is repeated at intervals of 3–4 seconds, and to the listener familiar with it, similar to the hoot of the European

tawny owl The tawny owl (''Strix aluco''), also called the brown owl, is commonly found in woodlands across Europe to western Siberia, and has seven recognized subspecies. It is a stocky, medium-sized owl, whose underparts are pale with dark streaks, ...

. Another call, which is given by both sexes, is a single soft mewing "wooh". They snap their bills to communicate, as do many owls.

Distribution

It is widely spread across the African tropical rainforest; also found on

Bioko Bioko (; historically Fernando Po; bvb, Ëtulá Ëria) is an island off the west coast of Africa and the northernmost part of Equatorial Guinea. Its population was 335,048 at the 2015 census and it covers an area of . The island is located of ...

Habitat

Their habitat is primarily forest, forest clearings, and

cardamom Cardamom (), sometimes cardamon or cardamum, is a spice made from the seeds of several plants in the genera ''Elettaria'' and ''Amomum'' in the family Zingiberaceae. Both genera are native to the Indian subcontinent and Indonesia. They are r ...

plantations. They range from sea-level up to about , in

Cameroon Cameroon (; french: Cameroun, ff, Kamerun), officially the Republic of Cameroon (french: République du Cameroun, links=no), is a country in west- central Africa. It is bordered by Nigeria to the west and north; Chad to the northeast; th ...

Biology

Like most owls Fraser's eagle-owl is a

nocturnal Nocturnality is an ethology, animal behavior characterized by being active during the night and sleeping during the day. The common adjective is "nocturnal", versus diurnality, diurnal meaning the opposite. Nocturnal creatures generally have ...

bird, roosting during the day hidden by leaves, about above the ground. The roost site is often located by small, diurnal birds which

mob Mob or MOB may refer to: Behavioral phenomena * Crowd * Smart mob, a temporary self-structuring social organization, coordinated through telecommunication Crime and law enforcement * American Mafia, also known as the Mob * Irish Mob, a US crim ...

the owl. The birds stop roosting at dusk and become active. Singing is most often in the early evening and just after dusk, but they will also sing just before dawn. Its main prey is small mammals, such as mice, squirrels and

galago Galagos , also known as bush babies, or ''nagapies'' (meaning "night monkeys" in Afrikaans), are small nocturnal primates native to continental, sub-Sahara Africa, and make up the family Galagidae (also sometimes called Galagonidae). They are ...

s, and it also takes birds,

frog A frog is any member of a diverse and largely carnivorous group of short-bodied, tailless amphibians composing the order Anura (ανοὐρά, literally ''without tail'' in Ancient Greek). The oldest fossil "proto-frog" '' Triadobatrachus'' is ...

s, reptiles, insects and other arthropods as well as occasionally feeding on fruit. The breeding biology of Fraser's eagle-owl is little known. In

Gabon Gabon (; ; snq, Ngabu), officially the Gabonese Republic (french: République gabonaise), is a country on the west coast of Central Africa. Located on the equator, it is bordered by Equatorial Guinea to the northwest, Cameroon to the north ...

they are reported as singing in June–September but breeding seems to take place throughout the year, apparently varying geographically with egg-laying being recorded in February in

Liberia Liberia (), officially the Republic of Liberia, is a country on the West African coast. It is bordered by Sierra Leone to its northwest, Guinea to its north, Ivory Coast to its east, and the Atlantic Ocean to its south and southwest. It ...

, through to December in

Uganda }), is a landlocked country in East Africa. The country is bordered to the east by Kenya, to the north by South Sudan, to the west by the Democratic Republic of the Congo, to the south-west by Rwanda, and to the south by Tanzania. The south ...

and

Democratic Republic of Congo The Democratic Republic of the Congo (french: République démocratique du Congo (RDC), colloquially "La RDC" ), informally Congo-Kinshasa, DR Congo, the DRC, the DROC, or the Congo, and formerly and also colloquially Zaire, is a country in ...

. As nestlings have been found on the ground then it has been suggested that Fraser's eagle-owl may nest on the ground; however, there has been at least one record of a nestling observed in a tree cavity. The eggs are white with no markings. The juveniles are apparently dependent on the adults for a long time and retain their juvenile plumage for about a year.

Taxonomic notes

Fraser's eagle-owl and the

Usambara eagle-owl The Usambara eagle-owl, also called the East African nduk eagle-owl or Vosseier's eagle-owl, (''Bubo poensis vosseleri'') is a taxon of owl in the family Strigidae. It is now regarded as a subspecies of Fraser's eagle-owl (''Bubo poensis''). It i ...

''Bubo vosseleri'' have been considered as conspecific.

References

{{Taxonbar, from=Q629757 Fraser's eagle-owl Birds of the Gulf of Guinea Birds of the African tropical rainforest Birds of prey of Sub-Saharan Africa Fraser's eagle-owl Fraser's eagle-owl Taxonomy articles created by Polbot