The Whimbrel (Numenius phaeopus) is a wader in the large family Scolopacidae. It is one of the most widespread of the curlews, breeding across much of subarctic North America, Europe and Asia as far south as Scotland.
This is a common migrant to Singapore. – Sungei Buloh Wetland Reserve
It can be found on mudflats.
It has a long down-curved bill and distinctive crown stripes.
Source: Inaturalist
