Iduna opaca
Silhouette: Sheatherius · PhyloPic
In 3 days ~10%
The western olivaceous warbler (Iduna opaca), also known as the isabelline warbler, is a "warbler", formerly placed in the Old World warblers when these were a paraphyletic wastebin taxon. It is now considered a member of the acrocephaline warblers, Acrocephalidae, in the tree warbler genus Iduna. It was formerly regarded as part of a wider "olivaceous warbler" species, but as a result of modern taxonomic developments, this species is now usually considered distinct from the eastern olivaceous warbler, Iduna pallida.
It is a small passerine bird, found in dry open country, including cultivation, with bushes or some trees. Two or three eggs are laid in a nest in low undergrowth or a bush. Like most warblers, the western olivaceous warbler is insectivorous.
It is a medium-sized warbler, more like a very pale reed warbler than its relative the melodious warbler. The adults have a plain pale brown back and whitish underparts. Its body length is about 13–14 centimetres (5.1–5.5 in), wingspan 18–21 centimetres (7.1–8.3 in) and weight 8–13 grams (0.28–0.46 oz). The bill is strong and pointed and the legs grey. The sexes are identical, as with most warblers, but young... Wikipedia →
| # | Park | Country | Daily sighting probability |
|---|---|---|---|
| 1 | Niokolo-Koba National Park | 🇸🇳 Senegal | |
| 2 | Doñana National Park | 🇪🇸 Spain |
| # | City | Country | Daily sighting probability |
|---|---|---|---|
| 1 | Marrakesh | 🇲🇦 Morocco | |
| 2 | Maiduguri | 🇳🇬 Nigeria | |
| 3 | Ouagadougou | 🇧🇫 Burkina Faso | |
| 4 | Rabat | 🇲🇦 Morocco | |
| 5 | Serrekunda | 🇬🇲 Gambia | |
| 6 | Dakar | 🇸🇳 Senegal |
Rare
Under 5% of wildlife watchers report a Western Olivaceous Warbler sighting in Dakar on a given day, based on 7 verified sightings from GBIF citizen-science data. It is the 141st most-seen of the 152 birds we can rate there. Over three days the chance rises to about 10%, if each day is a fresh chance.
April and September
In those months about 10% of wildlife watchers report a Western Olivaceous Warbler in Dakar on a given day, against under 5% in May–August and October–March, the lowest months. Those are among Dakar's wettest months, with about 90 mm of rain a month against almost none in May.
Between 9 am and noon
Across all the parks we cover, that three-hour window holds the most Western Olivaceous Warbler sightings with a recorded time, and about 8 in 10 of them come between 6 am and 6 pm: it is a daytime animal.
6th of 6
Of the 6 cities where we can rate Western Olivaceous Warbler sightings, Dakar ranks 6th at under 5%. The best odds are in Marrakesh (Morocco, about 10%), Maiduguri (Nigeria, about 10%) and Ouagadougou (Burkina Faso, about 10%).
Same family: Acrocephalidae
The closest relatives of the Western Olivaceous Warbler that you can see in Dakar (family Acrocephalidae, Reed Warblers and Allies) are Sedge Warbler (about 10%), Greater Swamp Warbler (about 10%) and Eurasian Reed-Warbler (about 10%), with each one's daily chance of a sighting.
GBIF citizen-science records
It is estimated from how often the Western Olivaceous Warbler is recorded against all the birds logged in Dakar (7 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.
