The brown fish owl (Ketupa zeylonensis) is a large typical owl belonging to the family Strigidae.
These brown fish owl species are distributed in Turkey, Iran, Pakistan, India, Nepal, Bhutan, Bangladesh, Sri Lanka, Myanmar, China, Hong Kong, Thailand, Cambodia, Laos, Vietnam and Malaysia. These owl species are possibly extinct in Israel, Iraq, Jordan, Lebanon and Syria. There are four recognized subspecies of brown fish owl.
Brown fish owl - Overview
- Scientific name: Ketupa zeylonensis
- Species author: (Gmelin, 1788)
- Synonyms/Protonym: Strix zeylonensis J. F. Gmelin, 1788, Bubo zeylonensis
- Family: Strigidae › Strigiformes › Aves › Chordata › Animalia
- Vernacular names: English: Brown fish owl, Chinese: 褐渔鸮, French: Kétoupa brun, German: Fischuhu, Spanish: Búho pescador de Ceilán, Russian: Бурый рыбный филин, Japanese: ミナミシマフクロウ, Malay: Burung Hantu Ikan
- Other names: Brown Fish-Owl
- Distribution: Turkey, Iran, Pakistan, India, Nepal, Bhutan, Bangladesh, Sri Lanka, Myanmar, China, Hong Kong, Thailand, Cambodia, Laos, Vietnam, Malaysia
- Diet and feeding habits: fish, frogs, crabs, shrimp, snakes, lizards
- IUCN status listing: Least Concern (LC)
Appearance, physical description and identification
The brown fish owl (Ketupa zeylonensis) is a large bird measuring 50 to 60 cm in length and weighing 1100 to 1300 grams. The wingspan is 120 to 140 cm.The females are larger than the males. These species have prominent ear-tufts, which hang horizontally to the sides. The upperparts are reddish brown with numerous dark streaks.
The lower parts are paler, fulvous to whitish. There are dark brown vertical streaks and fine horizontal barring. The facial disc is not sharply defined. The throat is whitish.
The bill is dark gray and irises are orange-yellow. The feet are yellowish. The sub-adults are paler. Except for the size, there is no difference between the sexes. Their call is a deep, trisyllabic "hoo-hoo-hoo" sound
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| Birds of India - Image of Brown fish owl- Ketupa zeylonensis by Koshy Koshy |
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| Indian birds - Picture of Brown fish owl- Ketupa zeylonensis by Baluperoth |
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| Birds of India - Photo of Brown fish owl- Ketupa zeylonensis by Baluperoth |
Origin, geographical range and distribution
The brown fish owl species are distributed in Turkey, Iran, Pakistan, India, Nepal, Bhutan, Bangladesh, Sri Lanka, Myanmar, China, Hong Kong, Thailand, Cambodia, Laos, Vietnam and Malaysia.The nominate subspecies K. z. zeylonensis is distributed in Sri Lanka. The subspecies K. z. orientalis is distributed in northeast Myanmar, southeast China, Thailand, Malaysia, Cambodia, Laos and Vietnam.
The owl subspecies K. z. leschenaulti is distributed in north Pakistan, India, Myanmar and Thailand. The subspecies K. z. semenowi is distributed in Turkey, Iran, southeast Pakistan and northwest India.
The brown fish owl populations in Israel, Iraq, Jordan, Lebanon and Syria are possibly extinct. Vagrant birds have been observed in Seychelles. The Important Bird and Biodiversity Areas (IBA) of these species in Jordan is Wadi Yarmuk and IBA in Turkey is Dimçay Valley.
Ecosystem and habitat
These brown fish owl species have moderate forest dependency. These species occur in altitudes from 0 to 1900 meters. These owl species inhabit artificial ecosystems like plantations and rural gardens.The natural ecosystems of these species includes tropical and subtropical dry forests, Deciduous and semi-deciduous forests, tropical and subtropical moist lowland forests, open evergreen forests, freshwater marshes, well-vegetated ravines, rivers, steep river banks, streamside forests and creeks.
Diet and feeding behavior
The diet of these brown fish owl species is mostly fish. A variety of prey animals like frogs, crabs, shrimp, snakes and lizards are their primary food. These owls are nocturnal but have been observed to hunt during daytime, especially in cloudy weather.The brown fish owl positions itself on a rock overhang or hanging perch over water and on spotting a prey glides over the water and grabs the food by quickly extending its long legs. Sometimes, they wade in the water to catch a prey. They have been observed to feed on carrion.
Reproduction and breeding habits
The breeding season of the brown fish owl is from november to March in Indian subcontinent. The laying season is from January to April in Sri Lanka. The breeding season is in December in Malay peninsula.These owl species pair for life. The female is slightly larger than the male. The nests are large holes and hollows in old trees, steep river banks, rock ledges and caves.
Sometimes, these owls use the abandoned nest of eagles and vultures. The typical clutch contains two eggs. The chick hatch out after 35 days and young fledge after seven weeks.
Migration and movement patterns
The brown fish owl species are non-migratory, resident birds.The populations of these owl species in higher altitudes come to lower valleys in winter. Post breeding, juvenile owls may disperse and establish in new locations within the range. They may make local movements for feeding and breeding within their range.
Conservation and survival
The global population size of the brown fish owl (Ketupa zeylonensis) has not been quantified. The overall population trend of these owl species is considered to be decreasing. Throughout its range it is reported to be uncommon. The generation length is 5.7 years. Their distribution size is about 17,200,000 sq.km.The brown fish owl (Ketupa zeylonensis) does not approached the thresholds for being Vulnerable, either under the range size criterion, or under the population trend criterion or under the population size criterion. Habitat degradation is the main threat that may endanger the survival of these owl species.
IUCN and CITES status
The IUCN (International Union for Conservation of Nature) has categorized and evaluated the species and has listed it as of "Least Concern". The CITES (Convention on International Trade in Endangered Species of Wild Fauna and Flora) status is ‘Evaluated’ for the brown fish owl (Ketupa zeylonensis) and listed in Appendix II.| Taxonomy and scientific classification of Ketupa zeylonensis | |
|---|---|
| Kingdom: | Animalia |
| Phylum: | Chordata |
| Class: | Aves |
| Order: | Strigiformes |
| Family: | Strigidae |
| Subfamily: | - |
| Genus: | Ketupa |
| Species: | K. zeylonensis |
| Binomial name: | Ketupa zeylonensis |
| IUCN status listing: |
 Least Concern |
1.Image source: https://en.wikipedia.org/wiki/File:Brown_Fish_Owl_(8566795379).jpg (cropped)
Image author: Koshy Koshy | License: CC BY 2.0 as on 4/5/17
2.Image source: https://commons.wikimedia.org/wiki/File:Brown_Fish_Owl_(Ketupa_zeylonensis)_of_Thrissur,_Kerala.JPG (cropped)
Image author: Baluperoth | License: CC BY-SA 4.0
3.Image source: https://commons.wikimedia.org/wiki/File:Brown_Fish_Owl_(Ketupa_zeylonensis)_in_Thrissur,_Kerala.JPG (cropped)
Image author: Baluperoth | License: CC BY-SA 4.0
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