Apus cooki
Silhouette: Ferran Sayol · PhyloPic
In 3 days ~10% in a week ~20%
Cook's swift (Apus cooki) is a small bird, superficially similar to a house martin. It is, however, completely unrelated to those passerine species, since swifts are in the order Apodiformes. The resemblances between the groups are due to convergent evolution reflecting similar life styles.
These birds have very short legs which they use only for clinging to vertical surfaces. The scientific name comes from the Greek απους, apous, meaning "without feet". They never settle voluntarily on the ground. Blyth's swifts spend most of their lives in the air, living on the insects they catch in their beaks.
Cook's swifts breed in limestone caves of Thailand, Myanmar and Indochina. The species has a green iridescence, a shallow tail fork and is a short distance migrant. A 2011 study has many taxonomists splitting this species from the fork-tailed swift complex.
These swifts build their nests on cliffs, laying 2–3 eggs. A swift will return to the same site year after year, rebuilding its nest when necessary. Cook's swifts are similar in size to common swift, and they are black except for a white rump. They can be distinguished from a partially leucistic common swift by the deeper tail fork, longer wings, bigger head and larger white throat patch. Wikipedia →
Call0:15
Laos · 2022
© Bram Piot · XC722413 · CC BY-NC-SA 4.0
| # | Park | Country | Daily sighting probability |
|---|---|---|---|
| 1 | Doi Inthanon National Park | 🇹🇭 Thailand | |
| 2 | Kaeng Krachan National Park | 🇹🇭 Thailand | |
| 3 | Khao Sok National Park | 🇹🇭 Thailand |
Rare
Under 5% of wildlife watchers report a Cook's Swift sighting in Kaeng Krachan National Park on a given day, based on 92 verified sightings from GBIF citizen-science data from 2019 to 2026. It is the 235th most-seen of the 360 birds we can rate there. Over three days the chance rises to about 10%, and over a week to about 20%, if each day is a fresh chance.
March–April and September
In those months about 10% of wildlife watchers report a Cook's Swift in Kaeng Krachan National Park on a given day, against under 5% in May–August and October–February, the lowest months.
Among the best
Of the 3 parks where we can rate Cook's Swift sightings, Kaeng Krachan National Park ranks 2nd at under 5%, level with the leaders once rounded. The best odds are in Doi Inthanon National Park (Thailand, under 5%).
GBIF citizen-science records
It is estimated from how often the Cook's Swift is recorded against all the birds logged in Kaeng Krachan National Park (92 verified sightings from 2019 to 2026), 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.
