The Pacific swift (Apus pacificus) is a highly aerial bird belonging to the swift family Apodidae.
The Pacific swift species are distributed in Indian subcontinent, central and east Asia, south Asia, southeast Asia and Australia. These swifts are the largest species among the genus Apus. There are five recognized subspecies of these swifts.
Pacific swift - Overview
- Scientific name: Apus pacificus
- Species author: (Latham, 1801)
- Synonyms/Protonym: Hirundo pacifica Latham, 1801
- Family: Apodidae › Apodiformes › Aves › Chordata › Animalia
- Vernacular names: English: Pacific swift, Chinese: 白腰雨燕, French: Martinet de Sibérie, German: Pazifiksegler, Spanish: Vencejo del Pacífico, Russian: Белопоясный стриж, Japanese: アマツバメ, Indonesian: Burung Kapinis Laut
- Other names: Fork-tailed Swift
- Distribution: Indian subcontinent, central and east Asia, south Asia, southeast Asia, Australia
- Diet and feeding habits: insects, bees, wasps, termites, moths, flies, crickets, grasshoppers, locust, flying ants, airborne spiders
- IUCN status listing: Least Concern (LC)
The five recognized subspecies of Pacific swift are: Apus pacificus pacificus (Latham, 1801), Apus pacificus kurodae Domaniewski, 1933, Apus pacificus salimali Lack, 1958, Apus pacificus leuconyx (Blyth, 1845) and Apus pacificus cooki (Harington, 1913).
Appearance, physical description and identification
The Pacific swift (Apus pacificus) is a large swift, measuring 15 to 20 cm in length and weighing 20 to 50 grams. The wingspan is 40 to 55 cm.These Pacific swift species have thickset spindle shaped body, protruding head, long pointed wings, broad rump and long, deeply forked tail. The upper parts are blackish except for a white rump band. The head is slightly paler.
The upper wings and tail of Pacific swift are black. The under wings are brown. The underparts are black. The whitish fringe to the feathers gives a scaly appearance to the body. Both the sexes appear similar. The juveniles have pale fringes to the wing feathers.
The eyes of Pacific swift are dark brown. The bill is small and black. The legs are very short and black. The legs are used for clinging to vertical surfaces and are of little use in walking. Their calls are a variety of twitters, “srreeeeerrr” "tsiririri" or harsher "spee-eer' sound.
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| Birds of India - Image of Pacific Swift - Apus pacificus by ozma |
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| Indian birds - Picture of Pacific Swift - Apus pacificus by ozma |
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| Birds of India - Photo of Pacific Swift - Apus pacificus by ozma |
Origin, geographical range and distribution
The Pacific swift species are distributed in India, Pakistan, Nepal, Bhutan, Bangladesh, China, Myanmar, Thailand, Laos, Vietnam, Cambodia, Taiwan (China), North Korea, South Korea, Japan, Mongolia, Russia, Kazakhstan, Malaysia, Singapore, Indonesia, Brunei, Philippines, Australia, Timor-Leste and Papua New Guinea.In India, these Pacific swift species are distributed in the states of Jammu and Kashmir, Himachal Pradesh, Punjab, Haryana, Uttarakhand, Sikkim, northern West Bengal, Assam, Arunachal Pradesh, Nagaland, Manipur, Maharashtra, Goa, Karnataka, Andhra Pradesh, Tamil Nadu and Kerala.
The Pacific swift nominate subspecies A. p. pacificus is distributed in Russia, Mongolia, northern China, Koreas and Japan. It winters in Indonesia, Timor-Leste, Papua New Guinea, Australia and northeast India.
The Pacific swift subspecies A. p. kurodae is distributed in east China, south Japan and Taiwan. It winters in Malaysia, Philippines and Indonesia. The Pacific swift subspecies A. p. salimali is distributed in east Tibetan Plateau and adjacent China.
The Pacific swift subspecies A. p. leuconyx is distributed in north Pakistan and north India.The Pacific swift subspecies A. p. cooki is distributed in southeast Asia and winters in peninsular Thailand.
Ecosystem and habitat
These Pacific swift species have low forest dependency. These species occur in altitudes from 0 to 4000 meters. The artificial ecosystems of these swift include urban areas.The natural ecosystems of these Pacific swift species include boreal forests, boreal shrublands, temperate shrublands, temperate forests, tropical and subtropical forests, tropical and subtropical shrublands and tropical and subtropical grasslands.
Diet and feeding behavior
The diet of these Pacific swift species is mostly flying insects. Aeroplankton (or aerial plankton), flies, airborne spiders, moths, butterflies, flying termites and ants, dragonflies, locust, cicadas, grasshoppers, crickets and mantises are their primary food.These Pacific swift species are excellent aerial foragers, hawking insects on the wing. They are exceptionally agile in flight and drink by skimming the water surface while flying. These swifts circle through the insect swarms in flocks.
The hatchlings are fed with food balls, a mass of insects bound together by saliva. In bad weather the chicks may not be fed for several days and the chicks survive on stored body fat.
Reproduction and breeding habits
The breeding season of these Pacific swift species is from March to May in Nepal. The breeding season of these swift species is from April to July in Indian Himalayas. In Japan the laying season is from June to August.The colonial nesting sites of these swifts are sheltered locations in caves, crevices in vertical rock faces and eaves and roofs of buildings. The nest is a half-cup shaped structure made from feathers, dry grass and other dry plant material collected in flight. These materials are glued to a vertical surface with saliva.
The typical Pacific swift clutch contains two or three white eggs. Both the parents incubate the eggs. The chicks hatch out after 17-18 days of incubation. The hatchlings are blind and altricial (relatively immobile and lack down feathers). The chicks fledge in about 40 days.
Migration and movement patterns
These Pacific swift species are highly migrant birds.The northern Pacific swift populations in north and northeast India, Nepal, north Bangladesh, Bhutan, northern Myanmar, central and northeastern China, Mongolia, North Korea, South Korea, Japan, northeast Kazakhstan, central and eastern Russia are breeding visitors.
These Pacific swift population migrate to south India, southern Myanmar, southeast Asian countries and Australia for wintering. Resident populations are distributed in southeastern Nepal, northern parts of Myanmar, Cambodia, northern Vietnam, Taiwan, south China.
Post breeding, the juveniles 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 Pacific swift (Apus pacificus) has not been quantified. The overall population trend of these species is considered to be stable. Throughout its range it is reported to be generally common. The generation length is 12.5 years. Their distribution size is about 27,600,000 sq.km.The Pacific swift (Apus pacificus) 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. Habitat loss is the main threat that may endanger the survival of these swift species.
IUCN and CITES status
The IUCN (International Union for Conservation of Nature) has categorized and evaluated the swift 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 ‘Not Evaluated’ for the Pacific swift (Apus pacificus).| Taxonomy and scientific classification of Apus pacificus | |
|---|---|
| Kingdom: | Animalia |
| Phylum: | Chordata |
| Class: | Aves |
| Order: | Apodiformes |
| Family: | Apodidae |
| Subfamily: | - |
| Genus: | Apus |
| Species: | A. pacificus |
| Binomial name: | Apus pacificus |
| IUCN status listing: |
 Least Concern |
1.Image source: https://commons.wikimedia.org/wiki/File:Apus_pacificus_-Japan_-flying-8_(1).jpg (cropped)
Image author: ozma | License: CC BY 2.0 as on 4/25/17
2.Image source: https://en.wikipedia.org/wiki/File:Apus_pacificus_-Japan_-flying-8_(2).jpg (cropped)
Image author: ozma | License: CC BY 2.0 as on 4/25/17
3.Image source: https://en.wikipedia.org/wiki/File:Apus_pacificus_-Japan_-flying-8.jpg (cropped)
Image author: ozma | License: CC BY 2.0 as on 4/25/17
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