Author Archives: Alan OwYong

About Alan OwYong

Retiree birder and photographer.

Observations of Gallinago Snipes at Labrador NR.

By Alan OwYong.

The fenced-up open fields at the former British Petroleum Refinery between Belayer Creek and Labrador Nature Reserve has been the foraging grounds of Pond Herons, Egrets and late this season, Gallinago Snipes.

Several ditches were left on the soft muddy ground by the tyres of grass cutting tractors. With the monsoon rains, an ideal wetland habitat that the snipes love was created. The long grasses also provide them cover as they move around looking for earthworms to fatten themselves for the long flight back north.

Taking an evening bath at one of the waterlogged ditches

Only the Javan Mynas were seen trying to steal the earthworms from the snipes. While the White-breasted Waterhens and the Malayan Monitor Lizards that were feeding there did not bother the snipes at all.

Javan Myna waiting for the snipes to pull out the earthworms from the soil.

On 30 March, we counted a total of 6 snipes all within a small area not to far from the fence. We will able to identify two Pin-tailed Snipes (G. sterura) that day from some of the excellent photos of their pin feathers at their tail when they preened after taking a bath.

Pin-tailed Snipe. Preening after a bath revealing the pin feathers at the tail.

I had a photo of another on 8 April whose tail spread did not show any pin or the broader feathers of the Swinhoe’s Snipe (G. megala). Ayuwat J. was not able to identify it without more photos but did not rule out a Common Snipe (G. gallinago).

Cannot be identified as the tail is not fully spread to show all the outer feathers. Could may a Common Snipe as well.

Unfortunately none of us managed to get any definitive photos of the other snipes before they all left on the 12 April between 12.30 pm and 4.00 pm. I was able to pin down this timing as there were 4 snipes resting in the grasses when I left at 12.30 pm. I came back later at 4 pm, scanned until dusk and could not find a single snipe. A day before, I noticed that they were not active at all. Hardly moving out from hiding in the grasses. It may be that they had enough food and resting to gain strength for the flight back. They could have moved to other parts of the field but there were no records of them since. This timing is interesting as I always assumed that they would normally depart in the night.

Three snipes well hidden by the long grasses

The extreme departure dates recorded in the Avifauna of Singapore were 21 March for Swinhoe’s, 4 April for Common and 24 April for the Pin-tailed. I did not check in ebirds. Based on these dates we may have to look for the Swinhoe’s much earlier next season.

As an aside, a total of 5 Chinese Pond Herons were counted on 9 April. No Javan or Indian Pond Herons were seen here. They were foraging close to the snipes without any drama. They were still around on the 11 April but also disappeared on the 12 April. If any of you have any later dates please let me know.

A fully ripe Chinese Pond Heron having its last meal before its long flight back.


Lim Kim Seng. Avifauna of Singapore. NSS 2009. Pintailed/Swinhoe’s/Common Snipe.

Bakewell. D. (2004). Keep Calm and Study Snipes Part 1 and 2.

Records Committee Report 2022

Records Committee Report 2022

By Lim Kim Seng

Chairman, Nature Society (Singapore) Bird Group Records Committee.

Cinereous Vulture Aegypius monachus at Singapore Botanic Gardens, 29 Dec 2021. Photo by Justin Jing Liang.

The Nature Society (Singapore) Bird Group Records Committee continues to receive records of new bird species to the Singapore List and rarities as it has done every year since the early 1980s. 2021 was an exceptional year with 12 new species in Category A alone being added to the List. This report updates the findings for the period, January 2021 – January 2022.

New Species

Seventeen new bird species were added to the Singapore List, bringing the total number of species to 421, up from 407 in 2021 (Lim 2021). These included thirteen additions to Category A, three additions in Category C and one addition in Category D.

Category A: Species which have been recorded in an apparently wild state in Singapore within the last thirty years

Javan Plover Charadrius javanicus

Two birds photographed on 16 July 2021 at Pulau Tekong by Frankie Cheong were the first record for Singapore and mainland Southeast Asia. Prior to this record, the Javan Plover was recorded from South Sumatra, Java east to the Lesser Sundas. In addition, examination of photos taken in June at the same site revealed three birds including a juvenile. This indicates probable breeding in Singapore or somewhere nearby. One individual was still present at the site on 15 September. Amazingly, another individual was also seen at the Marina East breakwater on 17 December 2021 by Pary Sivaraman, the second record for Singapore and the first from the Singapore mainland. 

Javan Plower, Charadrius javanicus at Pulau Tekomg on 16 July 2021. Photo by Frankie Cheong.

Wedge-tailed Shearwater Ardenna pacifica

One individual was seen found by a resident of the estate around Bishan-Ang Mo Kio Park on 23 June 2021. He brought it to the park seeking help for the weakened bird since there were bird photographers present according to William Khaw who photographed it. The bird was eventually rescued by ACRES but did not survive. This is the first confirmed record of the Wedge-tailed Shearwater for Singapore. It ranges widely in the tropical waters of the Pacific and Indian Oceans, and breeds on small tropical islands from hose off Japan to waters off Eastern and Western Australia. Two subspecies are known: A.p. pacifica and A. p. chlororhyncha.

Wedge-tailed Shearwater Ardenna pacifica at BAMK Park on 23 June 2021. Photo by William Khaw.

Christmas Frigatebird Fregata andrewsi

Previously in Category B. An immature bird photographed at Marina East breakwaters by Evelyn Lee on 26 January 2022 reinstates this species in Category A. The Christmas Frigatebird breeds only on Christmas Island but ranges widely in the Indo-Malay Archipelago during the non-breeding season.

Christmas Frigatebird Fregata andrewsi over Marine East on 26 Jan 2022. Photo by Evelyn Lee.

Cinereous Vulture Aegypius monachus

One with five Himalayan Vultures Gyps himalayensis at the Learning Forest, Singapore Botanic Gardens, on 29 December 2021 first spotted by Justin Jing Liang and Cecilia Yip and shortly after by Yip Jen Wei and Martin Kennewell was a first record for Singapore. The Cinereous Vulture breeds in western and south-eastern Europe, Algeria, the Middle East, Himalayas east to central Asia. 

Cinereous Vulture Aegypius monachus at Singapore Botanic Gardens on 30 Dec 2021. Photo by Vincent Yip.

Long-eared Owl Asio otus

An individual photographed being pestered by House Crows at Marina East Drive on 20 November 2021 by Choo Shiu Ling was our first record for Singapore. The Long-eared Owl has a wide distribution occurring in North America, Europe, Eurasia and Far Eastern Asia south to Northern Indian Subcontinent.  Four subspecies are known.

Long-eared Owl Asio Otus at Marine East on 20 Nov 2021. Photo by Choo Shiu Ling.

Black-thighed Falconet Microhierax fringillarius

Previously in Category B. Three records, all in 2021: A juvenile seen and photographed at a HDB block along Yishun Street 71 on 12 February 2021 by Lee Lay Na, an adult from Goldhill Avenue on 20 May 2021 by Art Toh and another adult at Jalan Mashhor from 9 to 12 July 2021 by Art Toh, Tan Choon Siang and Vincent Lao (Lim 2021b). The Black-thighed Falconet is resident in the Thai-Maly Peninsula, Sumatra, Borneo and Java. 

Black-thighed Falconet Microhierax fringillarius at Goldhill Ave on 20 May 2021. Photo by Art Toh.

Malayan Black Magpie Platysmurus leucopterus

Previously in Category B. One seen at Hindhede Quarry on 9 June 2021 by Vinod Saranathan, Kenneth Chow and Ash Foo was the first confirmed record since the 1950s. The Malayan Black Magpie is a forest resident of the Thai-Malay Peninsula and Sumatra. It was previously considered conspecific with Bornean Black Magpie, P. aterrimus

Malayan Black Magpie Platysmurus leucopterus at Hindhede Quarry on 9 June 2021. Photo by Kenneth Chow.

Siberian House Martin Riparia lagopodum

One seen at Neo Tiew Harvest Lane on 3 January 2021 by Mike Hooper and another at Marina East Drive on 28 December 2021 by Oliver Tan were the first records for the country. The Siberian House Martin breeds in north-eastern Russia, Mongolia and northern China and winters in Myanmar and Indochina. It was previously considered conspecific with Common House Martin, R. riparia.

Siberian House Martin Riparia lagopodum over Harvest Lane on 3 Jan 2021. Photo by Oliver Tan.

Pale-legged Leaf-warbler Phylloscopus tenellipes

An individual seen, sound recorded and photographed at Petai Trail, Central Catchment Nature Reserve, between 12 and 27 November 2021 by Yong Ding Li, Sreekar Rachakonda, T Ramesh, Tan Gim Cheong and Tan Kok Hui was the first acceptable record for Singapore. A sonogram is needed to distinguish this species from the near-identical Sakhalin Leaf Warbler, P. borealoides. The Pale-legged Leaf-warbler breeds in Manchuria and winters in Southeast Asia.

Pale-legged Leaf-warbler Phylloscopus tenellipes at Petai Trail CCNR on 25 Nov 2021. Photo by Tan Gim Cheong.

Common Starling Sturnus vulgaris

An adult seen at Marina East Drive on 13 December 2021 by Gabriel Koh and subsequently by many other observers was the first record for Singapore. It breeds in Europe and the Palearctic eastwards to Mongolia. Northern populations are migratory and winters south to Spain and Africa. It has also been introduced to Australia, New Zealand, North America, Mexico, Argentina, South Africa and Fiji. 12 subspecies have been described.

Common Starling Sturnus vulgaris at Marine East on 13 Dec 2021. Photo by Jenny Koh.

Spotted Flycatcher Muscicapa striata

One photographed at Kent Ridge Park on 15 October 2021 by Alex Kang was the first record for Singapore. It breeds most of Europe and the Palearctic and winters in Africa and south-western Asia. Five subspecies are known.

Spotted Flycatcher Muscicapa striata at Kent Ridge Park on 15 Oct 2021. Photo by Alex Kang.

Black Redstart Phoenicurus ochrorus

One female seen at Springwood Walk on 28 November 2021 by Ian Cash was initially identified as a Daurian Redstart. It was seen again 6 December 2021 by Art Toh who correctly identified it as a Black Redstart. This is a widespread breeder in Europe, Asia and northern Africa. Northern populations are migratory and winter in southern and western Europe and Asia, and north-west Africa, south to Morocco and east to central China. Between five and seven subspecies are known to exist.

Black Redstart Phoenicurus ochrorus at Springwood Walk on 6 Dec 2021. Photo by Art Toh.

Tree Pipit Anthus trivalis

One seen at the Ulu Pandan Park Connector (beside Clementi Road) on 23 October 2021 by Soo Kok Choong was our first record for Singapore. The Tree Pipit occurs through most of Europe and the Palearctic and migrates south to winter in Africa and Southern Asia. Two subspecies are known: A.t. trivialis and A.t. haringtoni

Tree Pipit Anthus trivalis at Ulu Pandan PC, besides Clementi Road, on 23 Oct 2021. Photo by Soo Kok Choong.

Category C: Species which although introduced by man have now established a regular breeding population which may or may not be self-sustaining

The following species have been accepted as new entrants in Category C: 

Masked Lapwing Vanellus miles

Previously in Category E (Lim 2009). A polytypic species ranging New Guinea, Australia and New Zealand, the Masked Lapwing was first recorded in Singapore when four birds were sighted at Lower Peirce Reservoir on 3-9 September 1994 (Lim 2009). They were believed to be escapees from the nearby Zoo. Subsequently, there were reports from other parts of the Central Catchment Nature Reserve, Kranji Reservoir, Lower Seletar Reservoir, Seletar Country Club, Tanah Merah and Marina East. The first breeding record was from Seletar Country Club on 24 November 2004 and, more recently, chicks have been seen at Marina East. This Australasian species appears established in the localities listed and is therefore added to Category C.

Masked Lapwing Vanellus miles at Marina East. Photo by Alan OwYong.

Milky Stork Mycteria cinerea

Previously in Category E (Lim 2009). The Milky Stork is a monotypic species with a range covering the Thai-Malay Peninsula, Indochina, Greater Sundas and Sulawesi (Clements 2007). It was first reported in Singapore when 2 birds were reported on 9-22 September 1997 at Seletar Farmway (Lim 2009). The birds were believed to be free-flying birds from the Zoo. Subsequently, sightings became regular in the north and northwest of Singapore. Breeding has not yet been reported outside the Zoo but juveniles are frequently seen and are indicative of local breeding.  

Milky Stork Mycteria cinerea at Chinese Gardens. Photo by Alan OwYong.

Painted Stork Mycteria leucocephala

Previously in Category E (Lim 2009). The Painted Stork is a monotypic species ranging from the Indian Subcontinent to South China and Southeast Asia (Clements 2007). It is a common escapee, presumably from free-flying stock from the Zoo, first reported in Singapore at Senoko on 29 March 1987 (Lim 2009). Subsequently, sightings have become frequent in coastal wetlands in the north and north-west of Singapore, especially at Sungei Buloh Wetland Reserve. Like the preceeding species, breeding has not yet been reported outside the Zoo but juveniles have been seen. Hybrids with the previous species are common and care should be taken to separate them.

Painted Stork Mycteria leucocephala. Photo by Alan OwYong.

Category D: Species which have occurred in an apparently wild state but for which the possibility of escape or release cannot be satisfactorily excluded

The following species have been accepted as a new entrant in Category D:

Ashy-headed Green Pigeon Treron phayrei

A male seen in the Central Catchment Nature Reserve on 9 Oct 2021 by Yip Jen Wei was the first record for Singapore. However, since it was not clear if the bird was a genuine straggler as it is over 1,000 km from its normal range, or whether it is a product of the regional cagebird trade, this record was assigned to Category D, pending further evidence.

Ashy-headed Green Pigeon Treron phayrei at CCNR on 9 Oct 2021. Photo by Yip Jen Wei.

Other updates to the Checklist

The taxonomy, nomenclature and systematics follow that of the latest IOC version 12.1 which was released in January 2022. 

An update done by the committee was to review species in Category C and apply a shorter timeframe to introduced species. Instead of 30 years as applied for species in Category A, Category C species must be present in the last ten years and there must be records of breeding within that period. As a result, two species, Crested Myna and Black-winged Starling, have been removed.

Another important change is an update on the nationally threatened species of Singapore using IUCN criteria and extending the coverage to include non-resident species except introduced species. This was possible through the excellent work of the Singapore Red Data Book Working Group for Birds, headed by Yong Ding Li. The recently completed re-assessment also highlighted the plight of wild birds in Singapore and the rest of the world from a multitude of threats of extinction including habitat loss and disturbance, poaching, pollution and climate change. 

Please click on the link to download the NSS Bird Checklist 2022.


We would like to thank the following observers for submitting their records for review and for the use of their photographs in this report: Ian Cash, Frankie Cheong, Choo Shiu Ling, Kenneth Chow, Ash Foo, Mike Hooper, Alex Kang, William Khaw, Gabriel Koh, Jenny Koh, Vincent Lao, Evelyn Lee, Lee Lay Na, Justin Jing Liang, Pary Sivaraman, T. Ramesh, Soo Kok Choong, Sreekar Rachakonda, Tan Choon Siang, Art Toh, Tan Gim Cheong, Tan Kok Hui, Oliver Tan, Vinod Saranathan, Vincent Yip, Alan OwYong, Yip Jen Wei and Yong Ding Li. Finally, thanks are also due to my fellow committee members for their expertise in the deliberation process:  Benjamin Lee, Lim Kim Keang, Tan Gim Cheong, Tan Kok Hui, and Yong Ding Li. 


Clements, J.F. (2007). The Clements Checklist of the Birds of the World, Sixth Edition. Christopher Helm, London.

Lim, K.S. (2009). The avifauna of Singapore. Nature Society (Singapore), Singapore.

Lim, K.S. (2021a). Records Committee Report 2021. Nature Society (Singapore) Bird Group Records Committee, Singapore. Accessed on 24th March 2022., K.S. (2021b). The Black-thighed Falconet in Singapore. Nature Society (Singapore) Bird Group, Singapore. Accessed on 24th March 2022.

Nesting time line of the Olive-backed Sunbird.

By Malathy.

After reading Alfred Chia’s article “Unexplained observations of an Olive-backed Sunbird Cinnyris jugularis, nesting” in the Singapore Bird Group’s blog, I would like to contribute my recent observations of a pair of Olive-backed Sunbirds nesting at my balcony.

Last December, I brought back a branch and set it over my house plants at my 5 room executive apartment balcony together with some hanging Spanish Moss. Days later, I noticed a pair of Olive-backed Sunbirds visiting my balcony and on 10 December 2021, they decided to build their hanging nest using the branch. We were delighted to welcome them to our home. It was an untidy nest and the balcony floor was littered with fallen nest materials, but we don’t mind. This was the first time that these sunbirds nested here.

Typical untidy hanging nest of the Olive-backed Sunbirds at my balcony garden.

Two eggs were laid on 24 December 2021. We saw the female sunbird incubating on and off during the day and full time during the night.

After two weeks on 8 Jan 2022, both eggs hatched. The parents were seen feeding the young with insects. They also take away the fecal sacs from the chicks to keep the nest clean. We can hear faint chirpings on the 13 Jan. The feeding intensified as the chicks got older and near fledging. 

Mummy sunbird feeding the ever hungry chicks

On 22 January, 29 days after egg laying, both chicks fledged one after another. Just before fledging the father sunbird was demonstrating and encouraging the chicks to fly. 

The two chicks days from fledging.

For the first few days, the chicks would sit at the balcony and fly to the trees around the neighborhood and return to the balcony a couple of times.

They did not come back to roost in the nest and must have left to explore the neighborhood as we did not see them again.

Interestingly, another pair of Olive-backed Sunbirds and a pair of Brown-throated Sunbirds came around on 26 January 2022 to check on the empty nest. They were seen discussing over who should be taking over the nest. 

On 29 Jan 2022, it was a pair of Olive-backed Sunbirds that took over the nest. They carried out some repairs and renovations daily and laid two eggs on the 5 February 2022. They are now incubating and we hope for another successful nesting.

All Photos by Malathy.

First ever sightings of 12 species of birds for Singapore in 2021, a summary

By Geoff Lim

The year 2021 was an incredible year with many species of birds seen for the first time in Singapore. Here’s a quick summary of what showed up.

1. Siberian House Martin Delichon lagopodum

Found by: Fadzrun A. (ID by Frank Rheindt)
Location: Neo Tiew Harvest Lane
Date: 3 January 2021
Remarks: another sighting on 28 December 2021 at Marina East by Oliver Tan

Siberian House Martin, 281221, MED, Art Toh, same 3

Siberian House Martin, photo by Art Toh, Marina East, 28 Dec 2021

2. Brown Fish Owl Ketupa zeylonensis

Found by: Jackie Yeo (ID by Tan Gim Cheong)
Location: Hindhede Nature Park
Date: 17 February 2021
Remarks: Jan Tan’s photo of an owl at Singapore Quarry on 3 August 2019 turned out to be a Brown Fish Owl , making hers the first sighting.

Brown and Buffy Fish Owl, 220221, Hindhede, TGC

Brown Fish Owl, shown next to a Buffy Fish Owl, composite photo by Tan Gim Cheong, Hindhede Nature Park, 22 Feb 2021

3. Wedge-tailed Shearwater Ardenna pacifica

Found by: William Khaw (ID by Eric Tan)
Location: Bishan – Ang Mo Kio Park
Date: 23 June 2021

Shearwater, 230621, BAMK, Art Toh

Wedge-tailed Shearwater, photo by Art Toh, Bishan-Ang Mo Kio Park, 23 June 2021

4. Javan Plover Charadrius javanicus

Found by: Frankie Cheong (ID by James Eaton)
Location: Reclaimed land off northeast SG
Date: 16 July 2021
Remarks: another sighting on 17 December 2021 at Marina East by Pary Sivaraman

Javan Plover, 150721, Tekong, Frankie Cheong

Javan Plover, photo by Frankie Cheong, 16 July 2021

5. Ashy-headed Green Pigeon Treron phayrei

Found by: Yip Jen Wei ( ID with Martin Kennewell)
Location: Dillenia Hut, Central Catchment
Date: 9 October 2021

1, AHGP, Art Toh, 101021, crop

Ashy-headed Green Pigeon, photo by Art Toh, CCNR, 10 Oct 2021

6. Spotted Flycatcher Muscicapa striata

Found by: Alex Kang (ID by Yang Chee Meng & Yong Ding Li)
Location: Kent Ridge Park
Date: 15 October 2021

4, Spotted FC, Geoff, 231021

Spotted Flycatcher, photo by Geoff Lim, Kent Ridge Park, 23 Oct 2021

7. Tree Pipit Anthus trivialis

Found by: Soo Kok Choong (ID by Vincent Yip)
Location: Ulu Pandan PCN – Clementi Road junction
Date: 23 October 2021

6, Tree Pipit, LKS, 311021

Tree Pipit, photo by Lim Kim Seng, Ulu Pandan PCN – Clementi Road junction, 31 Oct 2021

8. Pale-legged Leaf Warbler Phylloscopus tenellipes

Found by: Yong Ding Li, Sreekar Rachakonda
Location: Petai Trail, MacRitchie Reservoir
Date: 12 November 2021

Pale-legged Leaf Warbler, 251121, Petai, TGC

Pale-legged Leaf Warbler, photo by Tan Gim Cheong, Petai Trail, 25 Nov 2021

9. Long-eared Owl Asio otus

Found by: Choo Shiu Ling (ID by Tim Marshall)
Location: Marina East
Date: 20 November 2021

Long-eared Owl, 201121, MED, Shiu Ling FBBS, crop

Long-eared Owl, photo by Choo Shiu Ling, Marina East, 20 Nov 2021

10. Black Redstart Phoenicurus ochruros

Found by: Ian Cash (ID by Art Toh)
Location: Jambol Place
Date: 28 November 2021

Black Redstart, 061221, Jambol Place, Art Toh 1

Black Redstart, photo by Art Toh, Jambol Place, 6 Dec 2021

11. Common Starling Sturnus vulgaris

Found by: Gabriel Koh
Location: Marina East
Date: 13 December 2021

Common Starling, 141221, MED, Lee Chin Pong

Common Starling, photo by Lee Chin Pong, Marina East Drive, 14 Dec 2021

12. Cinereous Vulture Aegypius monachus

Found By: Cecilia Lee, Justin Jing Liang (ID by Martin Kennewell)
Location: Forest west of Tyersall Avenue
Date: 29 December 2021

Cinereous Vulture, 301221, SBG, Danny Khoo

Cinereous Vulture, photo by Danny Khoo, SBG, 30 Dec 2021

This is a summary of the birds seen for the first time in Singapore in 2021.

Accepted records will be inserted into the NSS Bird Checklist is due course.

Thanks to Art Toh, Tan Gim Cheong, Frankie Cheong, Geoff Lim, Lim Kim Seng, Choo Shiu Ling, Lee Chin Pong and Danny Khoo for allowing us to use their photos.

The different stages of our three resident Heron species at Pasir Ris Park.

By Seng Alvin.

We are blessed to have three resident heron species living and breeding at Pasir Ris Park, mainly due to the mangroves along Sungei Tampines, the tall trees lining Sungei Api Api and the abundant fishes around the rivers and sea coast. This is my backyard and I have been photographing these herons in varies stages of their life for a few years now.

This is a collection of some of my photos showing their different plumages from juvenile to adult and breeding.

The Striated Heron is the most common of the three and can be found waiting for passing fishes along the sides of the canal or perch at the lower branches of the mangroves. The brown upper and underparts of a juvenile ( top left) turning into pale grey ( top right) as it gets older. The plumage of the adult (bottom left) is all grey for both sexes. Its legs and facial skin turn reddish pink for breeding males ( bottom right).

The Black-crowned Night Herons are nationally threatened due to diminishing suitable habitat and they are fussy breeders. The fact they they are breeding here for over two decades underline the importance and fragility of the riverine and mangrove forests of the park. The juvenile ( bottom left) has orangey-yellow eyes, brown upperparts with white spots and streaks. The sub-adult ( top right) has no spots and the brown plumage has turned to pale gray. Eyes are darker. Adults ( top left) of both sexes has dark grey crown, mantle and back, yellow legs and two or more plumes. During breeding its legs turned orange ( bottom right).

Grey Herons are the most visible waterbird at the park foraging on the mud flats at low tides or perch high up on the tall trees around the park. They build communal large nests on trees by the river for easy access to the Tilapias there. The juveniles ( top right) has an overall blackish plumage and legs. Non-breeding adult males and females ( left top and bottom) share the same greyish plumage. The male adults ( bottom right) acquire pinkish red legs and facial skin during breeding.

I hope that these images help with identifying the varies ages of these herons.

Reference: A Field Guide to the Waterbirds of Asia 1993 Wild Bird Society of Japan

The Role of the NSS Bird Group Records Committee in the Documentation and Conservation of Wild Birds in Singapore

By Lim Kim Seng. Chair Bird Group Records Committee.

With the many recent new bird arrivals in Singapore the inevitable question of the origins of these new species, specifically if they are wild, released or escapees comes up. Many would like to know who evaluate their status and how is it done?

The quick answer is the Bird Records Committee of the country and in Singapore it is the Nature Society (Singapore) Bird Group Records Committee, or NSSBGRC, that had been doing this for the past three decades, with regular meetings several times a year.

The groundwork laid by then Malayan Nature Society Singapore Bird Group in the late 1970s and early 1980s by various pioneers such as Ng Soon Chye, Hugh Buck and Clive Briffett led to Chris Hails being appointed as the recorder for Singapore and the first bird checklist for the country being published in 1984. Chris left Singapore in 1988 and kick-started the formation of Nature Society (Singapore) Bird Group Records Committee (or NSSBGRC) in 1988 whose members included Clive Briffett, Lim Kim Keang, Lim Kim Seng and R. Subaraj. The current head is Lim Kim Seng who has over 40 years of birding experience in Singapore and Southeast Asia. The committee also includes Benjamin Lee from National Parks Board, Yong Ding Li from Birdlife International, Tan Kok Hui, current and past Bird Group Chairs, Tan Gim Cheong and Lim Kim Keang.

The task of NSSBGRC is not just to evaluate and verify new and rare records and submissions but more importantly to determine its status and assign a category to them. To do this, the RC consults with an advisory panel of global bird experts including Dr Nigel Collar, Dave Bakewell, Dr Phil Round, Dr David Wells, Dr Chaiyan Kasorndorkbua, Mike Chong, Peter Kennerley and Uthai Treesucon.

Another aspect of the work of the NSSBGRC is to keep tap of the status and taxonomic changes of the birds in Singapore. These changes include its abundance and status, i.e. abundant, common, uncommon or rare and status, i.e. resident breeder, winter visitor, passage migrant, non-breeding visitor or vagrant. The NSSBGRC also evaluates its breeding or non-breeding status based on available evidence.

The NSSBGRC also assigns a national threat status to every affected species and lists its IUCN global threat status. All this was made possible with the extensive and invaluable data from more than three decades of bird censuses, counts, surveys and studies conducted by the Nature Society (Singapore) Bird Group with the help of fellow birdwatchers and in collaboration with government agencies such as the National Parks Board.

All these classifications proved to be extremely useful for assessing the biodiversity importance of a nature site for conservation in Singapore, e.g. Sungei Buloh Wetland Reserve and the Rail Corridor, and listings on nationally threatened birds in the Singapore Red Data Book. 

Besides publishing and updating the rarities list, the NSSBGRC also publish a fully up-to-date annotated checklist at regular intervals. It has published updated checklists in 1991, 1999, 2007, 2011, 2014, 2015, 2017, 2018, 2019, 2020 and 2021 beginning with 284 species up to the current 407 species. The NSSBGRC also published a complete avifauna of Singapore in 2009 that captured its work in evaluation and documentation of wild birds as well as those of the early collectors since the 1800s.

The role of the NSSBGRC will always be to inform birdwatchers, observers and agencies of the latest updates by publishing an accurate and up-to-date national bird checklist, adopting the best practices in reviewing records of rarities and new species, and sharing them on suitable online platforms.

The NSSBGRC seeks experienced birders with in-depth knowledge of local and regional birds to carry on the work which must be transparent and democratic. It will continue to look to field experts, taxonomists, academics and ornithologists from across the globe for their advice. We wish to thank past and present members for their contributions in helping the committee to carry out this important work.

We hope that all birdwatchers in Singapore recognise the importance of their records and share them for the benefit of everyone, to obtain an accurate picture of the avifauna of Singapore with the ultimate objective of conserving our wild bird populations and its habitat.

The Black-Thighed Falconet in Singapore.


Lim Kim Seng


The Black-thighed Falconet Microhierax fringillarius was previously classified as a resident breeder as there had been specimens collected from Singapore as well as records since the 1920s and up to the 1990s (Lim 2009) but is likely to have become extirpated thereafter. It was re-categorized by the Nature Society (Singapore) Bird Group Records Committee, or NSSBGRC, as a non-breeding visitor as there have been no confirmed breeding record and no confirmed sightings for thirty years (Lim 2021). The Black-thighed Falconet was put into Category B, a category for wild birds, resident, visitor or vagrant, that have not been recorded for thirty years. In 2021 alone, however, there were three separate records of Black-thighed Falconet and as a result, it was re-instated in Category A by NSSBGRC.

Black-thighed Falconet was re-instated by the NSSBGRC in 2021. Photo taken at Panti Forest by Jimmy Chew.

Global Range, Habitat Requirements, Altitudinal Range, Breeding Habits and Conservation Status of Black-thighed Falconet

The Black-thighed Falconet is a monotypic species first described by Drapiez in 1824. It is one of five falconets in the world, all of which occur in southern China, South and Southeast Asia. Its natural range spans the Thai-Malay Peninsula, Sumatra, Borneo and Java. Its habitat is primary and secondary forests (including on limestone), edges of forests, rubber plantations, fruit orchards, cultivated land, parkland and wooded gardens up to 1,700 m (Ferguson-Lees & Christie 2000, Lim et al 2020, Wells 1999). The Black-thighed Falconet occurs as a common resident in most parts of its range and it is not known to undertake any movements (Robson 2000). In north Borneo, this species is replaced by the endemic White-fronted Falconet M. latifrons (Myers 2009).

In the Thai-Malay Peninsula, it breeds from November to July (Khoo 2021, Wells 1999). Nests are usually in tree cavities abandoned by woodpeckers and larger barbets, mostly in dead trees. In a site monitored in Perak, Malaysia, birds used a cavity in a limestone outcrop and nested successfully (Khoo 2021). Clutch size is three to six. The young remain with their parents for at least two months after fledging (Khoo 2021, Wells 1999).  It breeds from December to June in Borneo (Myers 2009). There is also evidence of communal feeding by birds other than parents, possibly by older siblings, and birds have also been seen to use old nest cavities as communal roost sites (Khoo 2021).

In Perak, Malaysia, they used cavities in Limestone outcrops to nest. Photo: Khoo Siew Yoong.

The Black-thighed Falconet is treated as “least concern” by IUCN (BirdLife International 2016).

Identification and Ecology of Black-thighed Falconet

The Black-thighed Falconet is one of the smallest raptors in the world at 15-17 cm in length from bill tip to tail tip. It is the same size as the White-fronted Falconet but smaller than Collared and Pied Falconets and has the distinction of being the smallest bird of prey of the world! In comparison, the Coppersmith Barbet Megalaima haemacephala measures 15-17 cm, Sunda Pygmy Woodpecker Yungipicus moluccensis, 13 cm and Yellow-vented Bulbul Pycnonotus goiavier measures 19-21 cm. Females are slightly larger than males and an adult weighs about 43 g (Wells 1999). In terms of its jizz, the Black-thighed Falconet has a big-headed, stout-bodied appearance with a medium-sized tail.

The small size of the falconet makes it hard to confuse with other birds although distance may make identification challenging as this species usually hawks from tall trees. It is mostly black on the head, eyestripe, ear patch, upperparts, bill, leg and tail, with mostly white on forehead, eyebrow and underparts, and orange-rufous on throat and lower breast to vent. Juveniles show pinkish horn bill and cere, rusty eyebrow and ear stripe, pale fine edges to upperparts and less rufous on lower underparts.

Its flight is rapid and direct, with fast wingbeats and sharp pointed wings, often accompanied by short periods of gliding.

Its voice is a shrill squeal kweer-week (Wells 1999).

Black-thighed Falconets hunt socially or alone, making sorties from a dead tree. Its diet is mainly arthropods, typically termites, butterflies and moths, dragonflies, carpenter bees, beetles, mantids, grasshoppers and cicadas, birds such as House Swift Apus nipalensis, sunbirds and munias, mammals such as bats and rats, and geckos (Khoo 2021, Wells 1999). Prey is usually snatched on the wing, occasionally from the ground, to be consumed from a perch, and there is evidence that falconets choose flowering trees with an abundance of nectar feeders to hunt (Wells 1999).

Birds indulge in head bobbing and tail wagging in close proximity and allo-preening has been observed (Wells 1999).

Historical Status of the Black-thighed Falconet in Singapore

The earliest reference to the occurrence of the Black-thighed Falconet in Singapore can be found in Bucknill & Chasen (1927) who stated that it “sometimes visit Singapore”. Gibson-Hill (1950) mentioned that it was “resident in small numbers” while RAFOS (1966-1969) and Tweedy (1970) mentioned the existence of several records in the 1960s.

There were no records until almost two decades when I found the first of four sight records within a period of seven years, all from a dead durian tree in my wooded garden in Jalan Ulu Sembawang in the north of Singapore. All records were of singles and included a juvenile seen on the following dates – 11 October 1979, 2 October 1983, 1 December 1983 and 12 April 1986 (Lim 1992). These records indicate the presence of a small and possibly breeding resident population in the area or that of non-breeding visitors from nearby Johor state, Malaysia. There were no further records from this site which was resettled and developed as part of the new Sembawang Estate in the early 1990s. Our most recent record was an adult seen on a dead tree, near the current Ranger’s Station, in the Central Catchment Nature Reserve on 7 October 1990 (Lim 2009).

In addition to these records, there were also four unconfirmed records between 1992 and 2005 from Sime Road, Loyang and Bukit Batok Nature Park. There are also nine specimens collected from MacRitchie Reservoir, Jurong and Singapore in the Lee Kong Chian Nature History Museum collection.  

Due to the fact that there have been no records for thirty years and also no confirmation of breeding, the Black-thighed Falconet’s status was reviewed by NSSBGRC in early 2020 as no longer fitting that of a wild bird for Category A, which is the category for all wild birds recorded within the last thirty years. It was re-categorised as belong to Category B, which is the category for all wild birds recorded within Singapore but not within the last thirty years (Lim 2021).

As fate would have it, soon after the release of the new checklist, news came of our first sighting of Black-thighed Falconet since 1990. This came from a juvenile that was seen and photographed by Lee Lay Na at a HDB block in Yishun Street 71 on 12 February 2021 (Tan, G.C. & Lim, G. 2021). The report of a juvenile is interesting as it indicates local or regional breeding.

A typical perch of the Black-thighed Faconet on top of tree at Goldhill Avenue by Art Toh.

There were two additional records, both also backed by photographs. One was a bird photographed using the top of a tree at Goldhill Avenue on 20 May 2021 by Art Toh (Tan, G.C. 2021) while the second was another adult from Jalan Mashhor on 9 July 2021, reported by Art Toh and Tan Choon Siang, and still present on 12 July 2021, reported by Vincent Lao (Lim, G. et al 2021).

A far away photo of the second adult falconet taken at Jalan Mansor two months later again by Art Toh.

These three sightings from 2021 have the effect of reinstating the Black-thighed Falconet into the Singapore List once again. At the moment, it is probably best considered a rare non-breeding visitor due to the short-term nature of their occurrences in 2021. Hopefully, one day, we will find them nesting in Singapore again.

Concluding Remarks

Birders and bird photographers are much more active than two decades ago. There are people at various locations in Singapore every day and most of them carry some sort of photographic equipment with them. This number of people watching birds daily is bound to yield rewards in the form of documenting the occurrence of rarities as well as species that are either new to Singapore or those thought to have been extirpated. Recent records of Javan Plover and Green Broadbill attest to this increased opportunity of detecting something really sensational!

Would-be falconet seekers are encouraged to focus on sites in the central and north of Singapore, where all confirmed sightings have been made since 1979. Bukit Brown would be another place to pay attention to given the recent record (and nearby, in Goldhill). Searches on Pulau Ubin may also yield results due to the island’s proximity to Malaysia as well as the island’s reputation for attracting Malaysian visitors. Prime habitats to look for this elusive raptor are the edges of forests and woodland as well as areas where there are tall trees or snags.

It is hoped that birders and bird photographers will continue to help us make new discoveries or re-discoveries in the case of the Black-thighed Falconet, the smallest bird of prey in the world.


I would like to thank Yong Ding Li for helpful suggestions with the drafting of this article, Jimmy Chew, Khoo Siew Yoong and Art Toh for the use of their photographs.


BirdLife International. (2016). Microhierax fringillarius. The IUCN Red List of Threatened Species 2016. Downloaded on 10 September 2021.

Bucknill, J.A.S & Chasen, F.N. (1927).  The birds of Singapore Island. Government Printing Office, Singapore.

Ferguson-Lees & Christie, D.A. (2001). Raptors of the World. Christopher Helm, London.

Gibson-Hill, C.A. (1950). A checklist of the birds of Singapore Island. Bull. Raffles Mus. No. 21: 132-183.

Khoo, S.Y. (2021). Breeding ecology of Black-thighed Falconets in Perak, Malaysia. Nature Society (Singapore) Bird Group.

Lim, G., Lee, I. & Tan, G.C. (2021). Singapore Bird Report – July 2021. Nature Society (Singapore) Bird Group.

Lim, K.S. (1992). Vanishing birds of Singapore. Nature Society (Singapore), Singapore.

Lim, K.S. (2009). The avifauna of Singapore. Nature Society (Singapore), Singapore.

Lim, K.S. (2021). Bird Records Committee Report (January 2021). Nature Society (Singapore) Bird Group.

Lim, K.S., Yong, D.L. & Lim, K.C. (2020). A field guide to the birds of Malaysia and Singapore. John Beaufoy Publishing, Oxford.

Myers, S. (2009). A field guide to the birds of Borneo. Talisman Publishing, Singapore.

Royal Air Force Ornithological Society (1966-1969). Bulletins of the Singapore Branch & unpublished correspondence with members.

Tan, G.C. (2021). Singapore Raptor Report, Late Spring Migration, April-June 2021. Nature Society (Singapore) Bird Group.

Tan, G.C. & Lim, G. (2021). Singapore Bird Report – February 2021. Nature Society (Singapore) Bird Group.

Tweedy, L. (1970). The birds of Singapore. Army Birdwatching Club (Far East).

Wells, D.R. (1999). The birds of the Thai-Malay Peninsula, Volume One: Non-passerines. Academic Press, London.

Nesting of Little Terns in Singapore.

LITTLE TERN (Sternula albifrons)

By Frankie Cheong

I came across some Little Tern nests in end May and early June at my place. There were at least 5 nests. Each nest, in a shallow depression in the sand, consisted of 2 to 3 eggs. Fig 1 & 2

Fig 1
Fig 2

I started to monitor them. The adult birds took turn to sit on the eggs, normally for around 2 hours, then the other bird would take over. Fig 3, 4.

Fig 3
Fig 4

Every time when people or vehicle passed by or moved too close to their nests, they would fly up and made lots of loud and alert calls . Fig 5.

Fig 5

In mid June, I started seeing the hatchings, these are day old chicks, most of the time they still hide under the parent for protection. Fig 6,7,8,9.

Fig 6
Fig 7
Fig 8
Fig 9

2 to 3 days later, these chicks started to venture out moving around close to the nest area.

As the place is a bare reclamation land without any trees and very hot during the day, these little chicks were smart enough to hide under some long grass to shade themselves from the sun. Fig 10, 11, 12, 13.

Fig 10
Fig 11
Fig 12
Fig 13.

The parents continued to bring food back for the chicks. Sometimes, they would use the fish to teach the chicks to move forward to catch, I believed this is part of the training for survival. Fig14.15.

Fig 14
Fig 15

I monitored them till mid July when all the chicks fledged. F 16, 17, 18 .

Fig 16

Likely this is a 2 to 3 weeks old chick. fig 17,18.

Fig 17

A slightly older one.

Fig 18

A family photo.

It was a great privilege to study and document the nesting of our only resident tern that breeds on mainland Singapore, even though this site is on an offshore island. The Little Tern is listed as a common resident, but suitable breeding sites across the island is diminishing. It was featured in Lim Kim Seng’s 1992 book “Vanishing Birds of Singapore” as vulnerable. At 2019 Mapletree Investment’s exhibition “Singapore Birds on the Blink” at Vivocity, it was one of the species highlighted.


Lim Kim Seng. Vanishing Birds of Singapore 1992.

Lim Kim Seng. The Avifauna of Singapore. 2009. Nature Society (Singapore)

First Records of the Javan Plover in Singapore

First Records of the Javan Plover in Singapore

By Frankie Cheong & Lim Kim Seng

Figure #1: Javan Plover photographed at Pulau Tekong on 16th July 2021. Photo © Frankie Cheong. Note the flesh-coloured long legs, buff breast patch and eyestripe, and white supercilium extending beyond eye.

     I (FC) was going for my usual round exploring the reclaimed land on Pulau Tekong on the morning of 16th July 2021. My main reason for going to this area was to follow up on a Pied Stilt Himantopus leucocephalus to get a better look since it is a rare breeding visitor in Singapore only recorded at this location to date.

Upon reaching the area, I heard the call of a Pied Stilt, so I stopped my car and scanned the area. I was not able to find it. However, I did see three waders busy foraging about 20 to 30 m away.  I pointed my camera and looked through the view finder to try and see what they were. They are appeared to me to be Kentish Plover Charadrius alexandrinus, a species known to be an uncommon winter visitor and passage migrant in Singapore (Lim 2009; Lim et al. 2020) so I just clicked a few shots for record purposes and continued to search for the stilt.

Once I had downloaded and processed my photographs, one of these plovers were identified as a “Kentish Plover” and subsequently shared online on a Facebook group. I was pleasantly surprised to received messages from Dave Bakewell and James Eaton were both saying that this could be something rarer than Kentish Plover. There was a mad rush to google and messages were flying. Later that day. James Eaton messaged me to confirm that this is a Javan Plover Charadrius javanicus, a species never before seen outside Indonesia and Timor Leste!

He wrote, the plumage is spot on for Javan (gingery breast sides and ear coverts) but it has a long, sleek appearance with quite long thin bill and very leggy typical of Javan”. I also sent a short report, with my photographs, to the Records Committee of the Nature Society (Singapore) Bird Group as this species was not on the official bird checklist for Singapore.

Subsequently, I went back to my archives because I remember seeing the same plovers some time ago at Pulau Tekong. Indeed, I have some badly taken photos on 20th June 2021! There were also three birds, one of which looked like a juvenile. I sent these photos to James Eaton and he concurred that this was a juvenile, which meant that breeding could be taken place for the first time here in Singapore and outside Indonesia and Timor Leste! So, not only was this a new species for Singapore, it was also a new breeding record for Singapore! In addition, this was also a new record for continental Southeast Asia! What a mega tick! The three birds were still there on 2nd August.

If accepted by the Records Committee, these will be the first records, and the first breeding record of the Javan Plover in Singapore, something unprecedented since a similar event when Savanna Nightjar Caprimulgus affinis turned up in 1988 (Lim 2009, Lim et al 2020).

Status and Range of Javan Plover

The Javan Plover is a monotypic resident shorebird found across Java, the Lesser Sundas, southern Sumatra (Lampung) Bangka and Belitung (Iqbal et al. 2013; Iqbal 2015, Eaton et al 2016). The species is locally common at a number of sites it is known from in Indonesia (e.g. Jakarta Bay). The species is essentially endemic to Indonesia and Timor-Leste until the Singapore records. The records from the south-east coast of Sumatra and Belitung are fairly recent (within the last decade) and suggests a northward trajectory of range expansion of the species. The species occurs in a variety of habitats ranging from beaches and shrimp ponds to coastal mudflats and wetlands, occasionally straying into semi-open scrubland. The Singapore records suggest a northward expansion of its range towards continental Southeast Asia, and the species may already be occurring undetected in the Riau Archipelago, e.g. on Bintan (Yong, D.L., Adha Putra, C. in litt.). The Javan Plover is rated as globally Near-Threatened in view of its small and declining range (BirdLife International 2021).

Identification of the Javan Plover

The Javan Plover is a small plover with sandy brown upperparts, white lores, white supercilium extending behind eye and white collar, buff-coloured eyestripe and breast patches. Its bill is long and black and its legs are long and flesh-coloured. Compared to Kentish Plover, it has a bigger head with a less sloping forehead, a slenderer body and distinctly longer legs. The Malaysian Plover Charadrius peroni is similar but is shorter-billed with distinctly mottled upperparts. The Swinhoe’s Plover Charadrius dealbatus can be differentiated from the other two plovers by its head shape (steep forehead), the broad, white supercilium extending almost to the collar, the absence of the dark patch on its lores (giving it a ‘white-faced’ appearance), its shorter bill and legs.

Recommendations for future fieldwork

More fieldwork needs to be conducted in coastal (wetland) habitats around Singapore and its offshore islets as well as southern Peninsular Malaysia and the Riau Archipelago to determine if the Javan Plover has established a presence further northward as the Singapore records would suggest. There are known areas of coastal wetlands used by shorebirds in the northern and western coastline of Bintan (Yong, D.L. in litt.) and these sites should be further surveyed for their shorebird communities.


I would like to thank Dave Bakewell and James Eaton for helpful comments on my photographs on Facebook. Thanks also go to Alan OwYong and Yong Ding Li for the use of his photograph of Kentish Plover and White-faced Plover, as well as input on the species from the region from Yong Ding Li and Chairunas Adha Putra.

Figure #2. Javan Plover photographed at Pulau Tekong on 16th July 2021. Photo © Frankie Cheong.

Figure #3. Javan Plover photographed at Pulau Tekong on 16th July 2021. Photo © Frankie Cheong.

Figure # 4 & 5. Javan Plovers photographed at Pulau Tekong on 20th June 2021. Photos © Frankie Cheong.

Figure # 6 & 7. Javan Plover photographed at Pulau Tekong on 20th June 2021. Photos © Frankie Cheong.


BirdLife International (2021) Species factsheet: Charadrius javanicus. Downloaded from on 31/07/2021.  

Eaton, J.A., van Balen, B., Brickle, N.W. & Rheindt, F.E. (2016). Birds of the Indonesian Archipelago. Greater Sundas and Wallacea. Lynx Edicions, Barcelona.

Iqbal, M. 2015. Javan Plover Charadrius javanicus on Belitung Island, a new site for Sumatra (Indonesia). Wader Study 122(2): 160–161.

Iqbal, M., Taufiqurrahman, I., Gilfedder, M. & Baskoro, K. 2013. Field identification of Javan Plover Charadrius javanicus. Wader Study Group Bull. 120(2): 96–101.

Lim, K.S. (2009). The avifauna of Singapore. Nature Society (Singapore), Singapore.

Lim, K.S., Yong, D.L. & Lim, K.C. (2020). A field guide to the birds of Malaysia and Singapore. John Beaufoy, Oxford.

Figure # 8. Kentish Plover at Marina East on 31st January 2021. Photo © Alan OwYong.

Figure #10. White-faced Plover at Marina Barrage by Yong Ding Li.

The first sighting of a juvenile Blue-winged Pitta on mainland Singapore.

By Joseph Lim.

On the morning of 16 July this year, I went hiking to the Central Catchment Forest, Mandai Track 15 to look for the Sambar deer, a former native but probably escapees from the zoo. I started the hike at 7.40 am and shortly reached a stream where sightings of the deer had been reported. I tread slowly and quietly anticipating the deer to appear anytime. Suddenly, I saw some small movements at the bare dark patches of the bushes about 5 meters away.

Surprised to see that it was a juvenile Blue-winged Pitta, a first for mainland Singapore.

It was a small bird and from the size and shape I could see that it was a pitta even though it was dark and shaded at 8 am in the morning. As I got nearer I could see it “hopping” around just like a pitta. Upon seeing me coming, the pitta jumped up and perched on a low branch, instead of getting skittish and flee. At one point the pitta turned and looked straight at me in absolute silence. From my photos, I can see that it was a juvenile Blue-winged Pitta, Pitta moluccensis, with duller plumage and gape. On checking with my friends I was told that this is the first mainland record of a juvenile Blue-winged Pitta. The previous sighting of a fledged juvenile was at Pulau Ubin also around July in 2016 where its nest was discovered ( See reference).

The gape, duller and less defined plumage of the juvenile Blue-winged Pitta

I tried to move in for a closer shot and to avoid the many mountain bikers coming through as this was a shared track at this spot. Unfortunately a biker went by fairly fast and spooked the bird. It quickly hopped and flew further into the bushes.

I wandered around the vicinity to look for it. Then I heard the calls of a Blue-winged Pitta coming from a forest patch about 20 meters away. It turned out to be another pitta, a bigger adult with brighter plumage and clear define plumage perched on a small tree, 3 meters from the ground.

The adult Blue-winged Pitta calling loudly from a small tree.

This adult Blue-winged Pitta was calling loudly and regularly  throughout my observations. It remained perched for about 3 minutes and flew deeper into the forests when I approached it for closer shots. I can only assumed that this is the parent bird.

Both the adult and the juvenile could not be located and was not seen again.

Reference :

1.‘First documented records of the Blue-winged Pitta Pitta moluccensis breeding in Singapore, BING WEN LOW, ALFRED CHIA, GIM CHEONG TAN, WEE JIN YAP & KIM KEANG LIM



     A. F. S. L. Lok1*, K. T. N. Khor2 , K. C. Lim3 and R. Subaraj4