Locustella certhiola
Silhouette: Afsarnayakkan · PhyloPic
In 3 days <5%
Pallas's grasshopper warbler (Helopsaltes certhiola), also known as the rusty-rumped warbler, is an Old World warbler in the genus Helopsaltes. It breeds in the eastern Palearctic: from the Altai Mountains, Mongolia and Transbaikalia to northeastern China, the Korean Peninsula, and islands in the Sea of Okhotsk (Sakhalin and Kuril Islands). It is migratory, wintering from India eastward to Indonesia. It is a rare migrant in Sri Lanka.
This bird was named after the German zoologist Peter Simon Pallas. The specific certhiola is a diminutive from the genus Certhia, the treecreepers. The sixth edition of Clements Checklist refers to this species as "Pallas's warbler", a name more commonly used for Phylloscopus proregulus.
This small passerine bird is found in tall grass with some thicker vegetation, usually close to water in bogs or wet meadows. From 4 to 7 eggs are laid in a nest on the ground in grass. This species is a very rare vagrant to western Europe. One of the best places to see this skulking species as a vagrant is Fair Isle, Shetland; for a species that only rarely appears in western Europe, it can be found there with some regularity. Wikipedia →
Recording0:34
Russia · 2012
© Natalya Andreyenkova · iNaturalist · CC BY-NC 4.0
Recording0:30
Thailand · 2025
© smathichong · iNaturalist · CC BY-NC 4.0
Recording0:43
Russia · 2025
© Татьяна · iNaturalist · CC BY-NC 4.0
| # | Park | Country | Daily sighting probability |
|---|---|---|---|
| 1 | Gobi Gurvansaikhan National Park | 🇲🇳 Mongolia | |
| 2 | Kaeng Krachan National Park | 🇹🇭 Thailand | |
| 3 | Cat Tien National Park | 🇻🇳 Vietnam |
| # | City | Country | Daily sighting probability |
|---|---|---|---|
| 1 | Phnom Penh | 🇰🇭 Cambodia | |
| 2 | Đà Nẵng | 🇻🇳 Vietnam | |
| 3 | Berhampore | 🇮🇳 India | |
| 4 | Kolkata | 🇮🇳 India | |
| 5 | Zhuhai [Macau] | 🇨🇳 China | |
| 6 | Bangkok | 🇹🇭 Thailand | |
| 7 | Ho Chi Minh City | 🇻🇳 Vietnam | |
| 8 | Coimbatore | 🇮🇳 India | |
| 9 | Jakarta | 🇮🇩 Indonesia | |
| 10 | Hong Kong | 🇨🇳 China |
Rare
Under 5% of wildlife watchers report a Pallas's Grasshopper Warbler sighting in Cat Tien National Park on a given day, based on 5 verified sightings from GBIF citizen-science data from 2019 to 2026. It is the 238th most-seen of the 244 birds we can rate there. Over three days the chance rises to under 5%, if each day is a fresh chance.
Any time of year
In every month with enough records, under 5% of wildlife watchers report a Pallas's Grasshopper Warbler in Cat Tien National Park on a given day, so our monthly data shows no clear season.
Between 7 and 10 am
Across all the parks we cover, that three-hour window holds the most Pallas's Grasshopper 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.
Among the best
Of the 3 parks where we can rate Pallas's Grasshopper Warbler sightings, Cat Tien National Park ranks 3rd at under 5%, level with the leaders once rounded. The best odds are in Gobi Gurvansaikhan National Park (Mongolia, under 5%) and Kaeng Krachan National Park (Thailand, under 5%).
GBIF citizen-science records
It is estimated from how often the Pallas's Grasshopper Warbler is recorded against all the birds logged in Cat Tien National Park (5 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.
