Search

Bristle-thighed Curlew

on 3rd September 2007

On 17th August 2007, Ong Tun Pin sent an image of a curlew, commenting, “I have just come back from a 10 day trip to a very exotic island destination.

1119.jpg

“Attached is a whimbrel-like wader that I hope you can guess as the name can be derived from one body feature shown in the picture (above). I know that wader is usually hard to id but this one has one famous body part that gives its name. Not found in Southeast Asia but at the edge of the oriental region.

“Would be nice if someone could tell me if this is a juvenile and whether it is in moulting. I was told that this bird becomes temporarily flightless during wing-moult. It was reluctant to fly and I was able to do some sort of wader ‘herding’ along the beach. But one still flew away after I have ‘cornered’ it at sand banks at 4 meters away. This is not the way we do wader-watching in Malaysia where often a combined effort of scoping 60x from far distance and lurking among tall grass still scares the waders away”

11113.jpg

It was an image of a Bristle-thighed Curlew (Numenius tahitiensis), a rare bird whose breeding population is concentrated on the mountain tundra in West Alaska. It is called bristle-thighed because of the elongated feather shafts seen at the rear flanks and thighs (left). These long, shiny ‘bristles’ are usually seen only when the bird is handled. However, Tun Pin was fortunate to have captured this feature in his image, a feature he could not see through the lens. This again shows the importance of photographic images in the study of birds and bird behaviour.

The bird winters exclusively on oceanic islands, especially small Polynesian islands. And this was where Ong Tun Pin encountered the curlew, when he was on a ten-day holiday in Tahiti in August 2007.

This is a highly migratory bird, making long distance, non-stop flight of at least 4,000 km over the open ocean. The adults begin to leave their breeding grounds from early July, followed by the juveniles in early August. They meet at their staging grounds on central Yukon Delta before migrating to their winter grounds in the South Pacific islands.

11112.jpg

The image above of the flying bird shows its chestnut rump without stripes. This is the diagnostic feature to separate it from Whimbrel (Numenius phaeopus).

In the wintering grounds, the bird moults and about 50% of the adults become flightless for about two weeks. This is the only shorebird known to have a flightless moult. This is not a problem where they winter in remote islands where there are no predators. However, when humans settle on these islands, the flightless moulting birds are at a serious handicap, especially with the introduction of domestic cats, dogs and even pigs.

The adults depart in early May while the immature birds spend all of their pre-breeding years on the wintering grounds.

Ong Tun Pin
Singapore
September 2007

References:
1. Gils, van J. & Wiersma, P. (1996). [‘Family Scolopacidae (Sandpipers, Snipes and Phalaropes]. Pp. 444-533 in del Hoyo, J., Elliott, A. & Sargatal, J. eds. Handbook of the birds of the world. Vol. 3. Hoatzin to Auks. Barcelona: Lynx Editions.
2. Kaufman, Kenn (1996). Lives of North American birds. Boston & New York: Houghton Mifflin Co.
3. Rosair, D. & Cottridge, D. (1995). Photographic guide to the waders of the world. London: Hamlyn.

If you like this post please tap on the Like button at the left bottom of page. Any views and opinions expressed in this article are solely those of the authors/contributors, and are not endorsed by the Lee Kong Chian Natural History Museum (LKCNHM, NUS) or its affiliated institutions. Readers are encouraged to use their discretion before making any decisions or judgements based on the information presented.

YC Wee

Dr Wee played a significant role as a green advocate in Singapore through his extensive involvement in various organizations and committees: as Secretary and Chairman for the Malayan Nature Society (Singapore Branch), and with the Nature Society (Singapore) as founding President (1978-1995). He has also served in the Nature Reserve Board (1987-1989), Nature Reserves Committee (1990-1996), National Council on the Environment/Singapore Environment Council (1992-1996), Work-Group on Nature Conservation (1992) and Inter-Varsity Council on the Environment (1995-1997). He is Patron of the Singapore Gardening Society and was appointed Honorary Museum Associate of the Lee Kong Chian Natural History Museum (LKCNHM) in 2012. In 2005, Dr Wee started the Bird Ecology Study Group. With more than 6,000 entries, the website has become a valuable resource consulted by students, birdwatchers and researchers locally and internationally. The views and opinions expressed in this article are his own, and do not represent those of LKCNHM, the National University of Singapore or its affiliated institutions.

Other posts by YC Wee

2 responses

  1. Hi Tun Pin,
    Nice to have you here. Welcome!
    Yes,such documentary shots to show closed-ups of body parts with cameras that put to such positive use is definately a +++.
    Thanks.

    Daisy

Leave a Reply

Your email address will not be published. Required fields are marked *

Categories
Archives

Overall visits (since 2005)

Clustrmaps (since 2016)