Chamaetylas poliocephala
Silhouette: Martin Bulla, based on François Desbordes' illustration · PhyloPic
In 3 days ~10% in a week ~20%
The brown-chested alethe (Chamaetylas poliocephala) is a species of bird in the Old World flycatcher family Muscicapidae. It has a discontinuous range of presence across the African tropical rainforest. Its natural habitats are subtropical or tropical moist lowland forest and subtropical or tropical moist montane forest.
The brown-chested alethe was formally described in 1850 by the French naturalist Charles Lucien Bonaparte based on a manuscript by Coenraad Temminck. Bonaparte gave the binomial name as Trichophorus (Griniger) and the locality as Africa. The locality has been restricted to the island of Bioko (formally Fernando Po). The specific epithet combines the Ancient Greek polios meaning "grey" with -kephalos meaning "-headed". The brown-chested alethe is now one of four species placed in the genus Chamaetylas that was introduced in 1860 by Ferdinand Heine.
Nine subspecies are recognised: Wikipedia →
| # | Park | Country | Daily sighting probability |
|---|---|---|---|
| 1 | Semuliki National Park | 🇺🇬 Uganda | |
| 2 | Kibale National Park | 🇺🇬 Uganda | |
| 3 | Queen Elizabeth National Park | 🇺🇬 Uganda | |
| 4 | Bwindi Impenetrable National Park | 🇺🇬 Uganda |
| # | City | Country | Daily sighting probability |
|---|---|---|---|
| 1 | Nairobi | 🇰🇪 Kenya |
Rare
Under 5% of wildlife watchers report a Brown-chested Alethe sighting in Nairobi on a given day, based on 47 verified sightings from GBIF citizen-science data. It is the 114th most-seen of the 234 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.
January, March and July
In those months about 10% of wildlife watchers report a Brown-chested Alethe in Nairobi on a given day, against under 5% in February, April–June and August–December, the lowest months.
Between 8 and 11 am
Across all the parks we cover, that three-hour window holds the most Brown-chested Alethe sightings with a recorded time, and about 8 in 10 of them come between 6 am and 6 pm: it is a daytime animal.
Only Nairobi, in our data
Nairobi is the only city on Wallace's Line with enough records to rate Brown-chested Alethe sightings: under 5% of wildlife watchers there report one on a given day.
Same family: Muscicapidae
The closest relatives of the Brown-chested Alethe that you can see in Nairobi (family Muscicapidae, Old World Flycatchers, Robins, and Chats) are White-eyed Slaty Flycatcher (about 40%), Rüppell's Robin-Chat (about 40%) and Cape Robin-Chat (about 20%), with each one's daily chance of a sighting.
GBIF citizen-science records
It is estimated from how often the Brown-chested Alethe is recorded against all the birds logged in Nairobi (47 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.
