The Himalayan swiftlet (Aerodramus brevirostris), a highly aerial bird, belongs to the family of swifts and swiftlets, Apodidae.
These species of swiftlets are distributed in Nepal, India, Bhutan, Bangladesh, Myanmar, Thailand, Malaysia, Indonesia, China, Vietnam, Laos and Singapore. The Himalayan swiftlet has the unique ability of echolocation to navigate in total darkness to reach their roosting and nesting sites in caves. There are three subspecies of these swiftlets.
Himalayan swiftlet - Overview
- Scientific name: Aerodramus brevirostris
- Species author: (Horsfield, 1840)
- Synonyms: Hirundo brevirostris Horsfield, 1840, Collocalia brevirostris Deignan, 1955
- Family: Apodidae › Apodiformes › Aves › Chordata › Animalia
- Common Name: Himalayan swiftlet
- Other languages: Chinese: 短嘴金丝燕, French: Salangane de l’Himalaya, German: Himalajasalangane, Spanish: Salangana del Himalaya, Russian: Гималайская салангана, Japanese: ヒマラヤアナツバメ, Indonesian: Burung Walet Gunung, Malay: Burung Layang-layang Himalaya
- Other names: Indian Edible-nest Swiftlet, Indochinese swiftlet, Chinese Swiftlet
- Distribution: Nepal, India, Bhutan, Bangladesh, Myanmar, Thailand, Malaysia, Indonesia, China, Vietnam, Laos, Singapore
- Diet and feeding habits: flying insects, grasshoppers, beetles, mantises, mayflies, dragonflies, crickets, moths, flies, sawflies, wasps, bees, cicadas, flying termites, flying ants, locust
- IUCN status listing: Least Concern (LC)
Appearance, physical description and identification
The Himalayan swiftlet (Aerodramus brevirostris) is a small highly aerial bird measuring about 13 to 14 cm in length and weighing 12 to 13 grams. The upperparts are dark grayish-brown in adult nominate species. The adult Himalayan swiftlets have clear pale grayish rump band, which is less distinct in juveniles. The underparts are uniform pale gray. There is a patch above and behind the bill.The body of the Himalayan swiftlet is slender and the tail is obviously forked. It has swept-back wings and in flight, it resemble a crescent. The wings are narrow, aiding fast flight. The bill is small but the gape is wide. There are bristles around the bill to help in catching flying insects. The legs are very short, preventing the swiftlet from walking or perching. However, the Himalayan swiftlet can cling to vertical surfaces.
The Himalayan swiftlet species roost and breed in colonies. During the day, they keep flying, feeding and drinking on the wings in open areas in forests. In the evening they return to their roost in caves and rest by clinging to the cave walls. These Himalayan swiftlets use echolocation for navigation in darkness within the breeding and roosting caves. They make echolocating double clicks sounds which are audible to humans. Their call is twittering "chit-chit" and a piercing "teeree-teeree" sound.
Origin, geographical range and distribution
The Himalayan swiftlet is distributed in India, Nepal, Bhutan, Bangladesh, Myanmar, Thailand, Laos, vietnam and China. Wintering birds occur in Bangladesh, South Thailand, Malaysia, Singapore, Indonesia and Andaman Islands (India).The Himalayan swiftlet subspecies A. b. brevirostris is distributed in North India (Himachal Pradesh, Uttarakhand, North West Bengal, Sikkim), Nepal, Bhutan, Northeast India, Myanmar, South China (Yunnan) and Thailand. Wintering populations of these subspecies are seen in Bangladesh, Thailand, Malaysia and Indonesia (Sumatra).
The Himalayan swiftlet subspecies A. b. innominatus is distributed in Central, South and East China and North Vietnam. These swiftlet subspecies winter in South Thailand, Malaysia, Andaman Islands (India) and Sumatra (Indonesia). The subspecies A. b. rogersi is distributed in East Myanmar and West Thailand. These subspecies winter in South Thailand.
Ecosystem and habitat
These Himalayan swiftlet species inhabit a wide range of open habitats such as highlands, particularly flying and feeding over wooded river valleys and open areas in forests. They roost in caves in the mountains. Breeding populations occur up to 4,500 m in Nepal and 2200 m in Bhutan.Diet and feeding habits
The diet of the Himalayan swiftlet is mostly flying insects like grasshoppers, beetles, mantises, mayflies, dragonflies, crickets, moths, butterflies, flies, sawflies, wasps, bees, cicadas, flying termites, flying ants and locust.Reproduction and breeding habits
The breeding season of these Himalayan swiftlet species is from April to June in India and Myanmar. These birds are colonial breeders. The nests are glued to the vertical walls of the caves. The nests may be touching one another. The small cup-shaped nest is constructed by the male Himalayan swift with saliva and moss. The normal clutch is two eggs and both the parents take part in caring the hatchlings.Migration and movement patterns
These Himalayan swiftlet species are mostly migratory. The nominate subspecies A. b. brevirostris leave their breeding grounds during August-October to reach their wintering grounds in Bangladesh, Thailand, Malaysia and Indonesia (Sumatra). They return to their breeding grounds in the early summer. The Himalayan subspecies A. b. innominatus winters in South Thailand, Malaysia, India (Andaman Islands) and Indonesia (Sumatra). The subspecies A. b. rogersi winters in southern parts of Thailand.Conservation status and concerns
The global population size of the Himalayan swiftlet has not been quantified. The overall population size is considered to be stable. Their generation length is 5 years. These swiftlet species have large range and population. The Himalayan swiftlet does not approach the thresholds for being Vulnerable either under the range size criterion or under the population trend criterion or under the population size criterion.The IUCN (International Union for Conservation of Nature) has categorized and evaluated the Himalayan swiftlet (Aerodramus brevirostris) and has listed it as of "Least Concern".
| Taxonomy and scientific classification of Aerodramus brevirostris | |
|---|---|
| Kingdom: | Animalia |
| Phylum: | Chordata |
| Class: | Aves |
| Order: | Apodiformes |
| Family: | Apodidae |
| Subfamily: | - |
| Genus: | Aerodramus |
| Species: | A. brevirostris |
| Binomial name: | Aerodramus brevirostris |
| IUCN status listing: |  Least Concern |
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