Cypsiurus balasiensis
Silhouette: Aviceda (vectorized by T. Michael Keesey) · PhyloPic
In 3 days ~60% in a week ~90%
The Asian palm swift (Cypsiurus balasiensis) is a small swift. It is very similar to the African palm swift, Cypsiurus parvus, and was formerly considered to be the same species. It is a common resident breeder in tropical Asia from India to the Philippines. The down and feather nest is glued to the underside of a palm leaf with saliva, which is also used to secure the usually two or three eggs. This is a bird of open country and cultivation, which is strongly associated with oil palms.
This 13 cm long species is mainly pale brown in colour. It has long swept-back wings that resemble a crescent or a boomerang. The body is slender, and the tail is long and deeply forked, although it is usually held closed. The call is a loud shrill scream.
Sexes are similar, and young birds differ from adults mainly in their shorter tails. Asian palm swift has very short legs which it uses only for clinging to vertical surfaces, since swifts never settle voluntarily on the ground.
These swifts spend most of their lives in the air, living on the insects they catch in their beaks. Asian palm swifts often feed near the ground, and they drink on the wing. Compilers: Stuart... Wikipedia →
| # | City | Country | Daily sighting probability |
|---|---|---|---|
| 1 | Tamluk | 🇮🇳 India | |
| 2 | Vasai-Virar | 🇮🇳 India | |
| 3 | Hajipur | 🇮🇳 India | |
| 4 | Hanoi | 🇻🇳 Vietnam | |
| 5 | Yangon | 🇲🇲 Myanmar | |
| 6 | Savar | 🇧🇩 Bangladesh | |
| 7 | Dhaka | 🇧🇩 Bangladesh | |
| 8 | Salem | 🇮🇳 India | |
| 9 | Tiruchirappalli | 🇮🇳 India | |
| 10 | Bangkok | 🇹🇭 Thailand |
Possible
About 30% of wildlife watchers report an Asian Palm-Swift sighting in Mumbai on a given day, based on 2,363 verified sightings from GBIF citizen-science data. It is the 23rd most-seen of the 283 birds we can rate there. Over three days the chance rises to about 60%, and over a week to about 90%, if each day is a fresh chance.
February
In that month about 40% of wildlife watchers report an Asian Palm-Swift in Mumbai on a given day, against about 10% in July, the lowest month. That is one of Mumbai's driest months, with almost no rain against 830 mm in July.
Between 2 and 5 am
Across all the parks we cover, that three-hour window holds the most Asian Palm-Swift sightings with a recorded time, and about half of them come between 6 am and 6 pm: it is most active around dawn and dusk.
23rd of 56
Of the 56 cities where we can rate Asian Palm-Swift sightings, Mumbai ranks 23rd at about 30%. The best odds are in Tamluk (India, about 80%), Vasai-Virar (India, about 70%) and Hajipur (India, about 70%).
GBIF citizen-science records
It is estimated from how often the Asian Palm-Swift is recorded against all the birds logged in Mumbai (2,363 verified sightings), calibrated against known sighting rates. Figures are rounded to the nearest 10% because citizen-science data supports honest approximations, not decimals, and months with records from fewer than five people show "—". How it works.
