Tarsiger cyanurus
Silhouette: Martin Bulla, based on François Desbordes' illustration · PhyloPic
In 3 days ~20% in a week ~40%
The red-flanked bluetail (Tarsiger cyanurus), also known as the orange-flanked bush-robin, is a small passerine bird in the Old World flycatcher family. It breeds in mixed coniferous forests in northern Asia, parts of central Asia, and northeastern Europe. It is migratory, wintering mainly in southeast Asia, in the Indian subcontinent, the Himalayas, Taiwan, and northern Indochina.
The red-flanked bluetail was formally described in 1773 as Motacilla cyanurus by the German naturalist Peter Simon Pallas based on specimens seen near the Yenisei river in Russia. The specific epithet combines the Ancient Greek κυανος/kuanos meaning "dark-blue" with -ουρος/-ouros meaning "-tailed". The red-flanked bluetail is now placed in the genus Tarsiger that was introduced in 1845 by the English naturalist Brian Houghton Hodgson. The genus name is from Ancient Greek tarsos, "flat of the foot" and Latin gerere, "to carry".
The red-flanked bluetail belongs to a group of insectivorous birds known as chats, that were formerly thought to be thrushes. Genetic analysis showed that they were in fact a type of Old World flycatcher, with the resemblance to thrushes being the result of convergent... Wikipedia →
| # | Park | Country | Daily sighting probability |
|---|---|---|---|
| 1 | Nikko National Park | 🇯🇵 Japan | |
| 2 | Cuc Phuong National Park | 🇻🇳 Vietnam | |
| 3 | Taroko National Park | 🇹🇼 Taiwan | |
| 4 | Doi Inthanon National Park | 🇹🇭 Thailand |
With luck
About 10% of wildlife watchers report a Red-flanked Bluetail sighting in Cuc Phuong National Park on a given day, based on 19 verified sightings from GBIF citizen-science data from 2019 to 2026. It is the 90th most-seen of the 159 birds we can rate there. Over three days the chance rises to about 20%, and over a week to about 40%, if each day is a fresh chance.
February
In that month about 20% of wildlife watchers report a Red-flanked Bluetail in Cuc Phuong National Park on a given day, against under 5% in April–June and August–November, the lowest months. That is one of Cuc Phuong National Park's driest months, with about 50 mm of rain against 390 mm in August. July has too few records to rate.
Between 2 and 5 pm
Across all the parks we cover, that three-hour window holds the most Red-flanked Bluetail sightings with a recorded time, and about 8 in 10 of them come between 6 am and 6 pm: it is a daytime animal.
Among the best
Of the 4 parks where we can rate Red-flanked Bluetail sightings, Cuc Phuong National Park ranks 2nd at about 10%, level with the leaders once rounded. The best odds are in Nikko National Park (Japan, about 10%).
Same family: Muscicapidae
The closest relatives of the Red-flanked Bluetail that you can see in Cuc Phuong National Park (family Muscicapidae, Old World Flycatchers, Robins, and Chats) are White-rumped Shama (about 40%), Rufous-tailed Robin (about 40%) and Fujian Niltava (about 30%), with each one's daily chance of a sighting.
GBIF citizen-science records
It is estimated from how often the Red-flanked Bluetail is recorded against all the birds logged in Cuc Phuong National Park (19 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.
