Asian Openbill

Asian Openbill
This species is defined as a Review Species . Please submit your records of this species via our record submission page .

Scientific Name: Anastomus oscitans

Malay Name: Upih-Siput Asia

Chinese Name: 钳嘴鹳

Range: Found from the Indian subcontinent to mainland Southeast Asia

Taxonomy: Monotypic.

Size: 68-81 cm

Identification: Adult has diagnostic dull yellowish-grey bill with open spaces between mandibles and long pinkish-grey legs. Body is mostly greyish-white with contrasting glossy black flight feathers and tail. Juvenile likes adult but body more brownish grey and bill has no spaces between mandibles.

Habitat: Freshwater marshes, flooded fields and padi fields.

Behaviour/Ecology: A small flock of 6 adults were observed feeding on Golden Apple Snails (an introduced species) at a flooded field along West Camp Road.

Local Status: Rare migrant

Conservation Status: Least Concern (BirdLife International 2016)

Featured reports: Mar 2022, Jul 2023, Aug 2023, Sep 2023, Oct 2023, Dec 2023, Jan 2024, Feb 2024, Mar 2024, Apr 2024, May 2024, Jun 2024, Jan 2025, Feb 2025

Past records in our database:

Showing only accepted records. Note that records currently under review are also not displayed, and the list may not be a full list of records of this species in Singapore. For more details, check the database here.

Migrant bar chart (see more bar charts):

Asian Openbill Anastomus oscitans
Average number of individuals by week based on Singapore Bird Database data, Jul 2014 to Jun 2024 (all records)
Peak week Mar 12-Mar 18
Early date 29 Jul 2023
Late date 20 Jun 2024
Bar chart not displayed for this species; the large influx in late 2019 with birds lingering behind into 2021, means a bar chart is not a proper representation of this species's abundance.
A massive influx of this species in Dec 2019 was one of the most interesting events in recent Singapore birding history.
Asian Openbill at West Camp Road. Photo credit: Francis Yap
Asian Openbill at West Camp Road. Photo Credit: Francis Yap
Asian Openbill at West Camp Road. Photo Credit: Francis Yap
Asian Openbill at West Camp Road. Photo Credit: Francis Yap
Asian Openbill at West Camp Road. Photo credit: Francis Yap
Asian Openbill at West Camp Road. Photo Credit: Francis Yap
Asian Openbill at West Camp Road. Photo Credit: Francis Yap

External Links:

Conservation Status: IUCN Red List Page

Sound Recordings: xeno-canto Link

Wikipedia Entry: Wikipedia Link

eBird Species page: eBird (Asian Openbill)

References:

BirdLife International. (2016). Anastomus oscitans. The IUCN Red List of Threatened Species 2016. https://dx.doi.org/10.2305/IUCN.UK.2016-3.RLTS.T22697661A93628985.en. Accessed on 1 January 2023

Robson, C. (2014). Field guide to the birds of South-East Asia (Second Edition). Bloomsbury Publishing, London.

RECOMMENDED CITATION

Bird Society of Singapore. (n.d.). Asian Openbill. Retrieved on April 11, 2025 from https://singaporebirds.com/species/asian-openbill.

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