Pacific Swift Bird Details
Apus pacificus
Pacific Swift
Prashant Cheed
John Latham in 1801
Apodiformes
Apodidae
Apus
Appearance :
Its plumage is Dark brown or black with a white rump patch. Wing are long, narrow, and crescent-shaped, excellent for fast and agile flying.
Behaviour :
Highly social birds, often found in flocks. They spend most of their life in flight, even eating and drinking while airborne. Non-territorial, often nesting in colonies.
Habitat :
Primarily forest edges, open woodland, and coastal regions. Also seen in urban areas and around cliffs for nesting. Found near large bodies of water, which provide abundant insect prey.
Diet :
Mainly insectivorous, feeding on flying insects such as beetles, flies, ants, and wasps. They catch prey while in flight.
Conservation Status :
Least Concern
Distribution :
The Pacific Swift breeds in eastern Asia, including Russia, China, Japan, Korea, and parts of Southeast Asia. During the non-breeding season, they migrate to parts of Australia, Papua New Guinea, and Southeast Asia.
Population Size :
The population is considered to be stable and abundant over much of its range.
Life Span :
Typically around 10-20 years in the wild, though exact data is limited.
Body And Tarsus:
- Body: Streamlined, slender body with long, narrow wings designed for high-speed flight.
- Tarsus Length: Short, about 5-6 mm.
Head And Bill :
- Head: Small and rounded, with a short, flattened forehead. Designed to minimize air resistance during flight.
- Eyes: Relatively large for their body size, aiding in vision during high-speed flight and insect hunting.
- Bill: Short, wide, and flat, adapted to catching insects while flying. The bill is inconspicuous but opens wide to help catch prey.
- Bill Length: Small, around 5-7 mm in length.
Length :
The Pacific Swift is around 18-20 cm in length from head to tail.
Neck :
Short and not very distinct, contributing to the bird's aerodynamic body shape.
Size :
Medium-sized swift.
Tail Details :
- Tail: The tail is forked but not deeply so. Helps in maneuvering during flight.
- Tail Length: 7-8 cm, though the exact length may vary slightly between individuals.
- Feathers: Dark brown to black plumage, with some iridescence in the sunlight. The white patch on the rump is a distinguishing feature.
Weight :
30-40 grams. The Pacific Swift is light, making it highly agile in the air.
Wing :
Long, narrow, and crescent-shaped wings. Designed for rapid flight and endurance, allowing the bird to cover large distances during migration.
Wing Span :
Approximately 40-45 cm.
Facial Feature :
The Pacific Swift has a small, inconspicuous face with a short, flat bill and large, dark eyes. The head is rounded, helping to reduce air resistance during flight.
Nest Details :
- Nest Location: Pacific Swifts typically nest on cliffs, crevices, caves, and sometimes on man-made structures such as buildings or bridges. They use small ledges or holes.
- Nest Structure: The nest is a shallow cup built from feathers, plant fibers, and other small materials bound together with the bird’s saliva. Swifts do not build elaborate nests, but the saliva hardens, providing enough structure to support the eggs.
- Nest Made up of: Saliva, feathers, small twigs, and other plant materials. The bird uses its sticky saliva to hold the materials together, attaching them to the surface on which the nest is built.
Breeding Season :
Breeding typically occurs in May to August.
Nesting Season :
Nesting happens during the breeding season, primarily from May to August.
Egg Color :
White
Egg Length :
Around 22-26 mm in length.
Egg Width and Weight :
- Egg Width: Approximately 14-16 mm in width.
- Egg Weight: Each egg weighs approximately 2-2.5 grams.
Clutch Size :
1 to 3 eggs per clutch. Most commonly, they lay 2 eggs.
No. of Broods :
Typically 1 brood per breeding season.
Incubation Period :
Around 18-23 days. Both parents take turns incubating the eggs.
Nestling Period :
The nestlings remain in the nest for approximately 35-40 days before fledging.
Vocalization :
Their calls are sharp, high-pitched, and often heard in flight. They typically produce a series of rapid, high-pitched "tseet" or "trrrr" sounds.
Sex Demorphism :
There is no notable sexual dimorphism in Pacific Swifts.
Migration Details :
- Migration Pattern: Long-distance migrant. The Pacific Swift migrates thousands of kilometers from its breeding grounds in northern Asia to its wintering grounds in Southeast Asia, Australia, and Papua New Guinea.
- Migration Period: Migration occurs between September to October (southward migration after breeding) and April to May (northward migration to breeding grounds).
- Migration Route: Breeding birds from East Asia (China, Japan, Korea, and Russia) fly southeast towards wintering grounds in Australia, Indonesia, and Papua New Guinea. The migration route typically involves passing over Southeast Asia and the South China Sea.
- Reasons for Migration: Seasonal changes in food availability (insects) and temperature drive their migration. Swifts migrate to warmer regions during winter to continue feeding on abundant flying insects, as colder regions experience a decline in insect populations during the winter.