In March 2007, the appearance of a Javan Pond Heron (Ardeola speciosa) in Darwin, Australia, had Aussie twitchers in a flap. The bird was apparently blown in from Indonesia with Cyclone George and subsequently took up residency in the northern suburbs. News of its presence spread quickly and twitchers from all corners of Australia flew in for a glimpse.

This year, also in March, the Javan Pond Heron was sighted at Singapore’s Lorong Halus (left). As expected, the appearance of the heron had our local twitchers in a similar flap.

The bird was in its breeding plumage and this confirmed its identity without any dispute. In the absence of this plumage it is extremely difficult to differentiate it from the Chinese Pond Heron (Ardeola bacchus).

The Chinese Pond Heron, on the other hand, is an uncommon winter visitor and local birders are familiar with it (right). Not so the Javan, reported in Lim (1997) as a probable vagrant. However, its earlier occurrences have been challenged by Wang & Hails (2007) who believe that the status of the Javan was, at most, “uncertain”. The earlier sightings in breeding plumage, were photographed at the Sungei Buloh Wetland Reserve in October 1994 and again in March 2003. Our field ornithologist Wang Luan Keng believes that these birds could be escapees from the zoo, which has some free-flying specimens.

For reasons unclear to us, the Javan Pond Heron was recently added to the checklist of birds produced by the Nature Society’s Bird Group Records Committee (see reference below). Now, if a species is a new record for the country, there should be proper documentation published somewhere. Birders would like to know whether the sighting in Sungei Buloh in 2003 convinced the Records Committee that the bird was a genuine wild species and the rationale for its acceptance. If not, was it a subsequent sighting? And by whom and when? Maybe I am not aware of such publication/s?

Pond herons that visited Singapore in the early years were always wearing their winter plumage, thus they were mostly assumed to be Chinese Pond Herons. However, some of the recent (post-1997) sightings were in their breeding plumage, thus making their identification as Javan Pond Herons more creditable. Apparently, more and more sightings of these birds in their breeding plumage have been reported during the recent years.

The probability of the Javan Pond Heron sighted at Lorng Halus being a wild bird is great, considering its location, away from the zoo and birdpark. The fact that there were clear images of the bird removes any doubt that it was a Javan. Images are now playing an important role in birding. For one, any reasonably good photographer can make an impact on new sightings, while in the past there would always be doubts until an experienced member of the Records Committee personally saw the bird.

It should also be noted that Lim’s field guide and checklist are popular publications for the lay birdwatchers, whose main interest is identification. On the other hand, the annotated checklist of Wang & Hails is a scientific document written for ornithologists and scientific-minded birders. The annotated checklist was peer reviewed and The Raffles Bulletin of Zoology where it was published is accepted by the scientific community as an international journal of repute.

Images by Lee Tiah Khee.

References:
1. Lim, Kim Seng (1997). Birds - An illustrated field guide to the birds of Singapore. Sun Tree, Singapore.
2. Lim, Kim Seng (2007). Pocket checklist of the birds of the Republic of Singapore. Nature Society (Singapore) Bird Group Records Committee.
3. Wang. L.K. & Hails, C. J. (2007). An annotated checklist of birds of Singapore. Raffles Bull. Zool. Suppl. 15:1-179.

On 10th March 2008, Choo Teik Ju was disturbed to find a dead heron dangling from the branch of a tree in the Marsh Garden at West Coast Park (left). One of its wings was entangled by a discarded fishing line, no doubt left by an irresponsible amateur angler.

Teik Ju visits the park almost every weekend to jog and bird watch. Invariably he found the areas around the Marsh Garden littered with discarded fishing lines. Many were dangling from the branches of trees and these obviously pose a danger to the wildlife there.

According to Teik Ju, “The Marsh Garden is home to Lesser Whistling-duck, Common Moorhen,
 White-breasted Waterhen, Stork-billed Kingfisher, Chinese Pond Heron, Cinnamon
 Bittern, Common Kingfisher, White-throated Kingfisher, Great Egret,
 Black-crowned Night Heron, Grey Heron, Owls and Eagles.”


He contacted the National Parks Board and was informed that the park is regularly patrolled by rangers. He was also informed that fishing is disallowed in the Marsh Garden.

Anglers need to be told that they should not leave fishing lines indiscriminately around and that such irresponsible behaviour is tantamount to littering.

Besides, it is illegal to fish in the Marsh Garden.

On the afternoon of 15th February 2008, Dr Leong Tzi Ming was taking a casual stroll along the Telok Kurau Canal near his home when he spotted a heron foraging in the shallow water of the canal.

Tzi Ming is familiar with Little Heron (Butorides striatus), Black-crowned Night Heron (Nycticorax nycticorax) and Little Egret (Egretta garzetta), but not this bird. His suspected it to be a Pacific Reef Egret (Egretta sacra).

According to our bird specialist R Subaraj, “This is indeed a dark-phase Pacific Reef Egret. I have seen him flying over East Coast Road by your canal a couple of times over the past month.”

These birds are usually seen singly or in pairs. And most pairs Subaraj saw consisted of a dark and a white morph.

The Pacific Reef Egret is an uncommon resident. Its typical habitats are rocky shores, exposed reef flats and sometimes along sandy shore and low-tide mud around mangroves. But in urbanised Singapore, our concretised canals are becoming feeding grounds for this as well as other herons like Grey, Night and Striated.

Image by Dr Leong Tzi Ming.

“On January 30th, Melanie Votaw (from USA), along with Shamla Subaraj and I, came across a Yellow Bittern (Ixobrychus sinensis) with a lizard in it’s bill, at Serangoon. Over the next 5 minutes, we watched the bird adjust the reptile into the right position before swallowing it completely.

“Yellow Bitterns are mostly migrants from the north and can be found in suitable areas throughout Singapore. They mainly feed at the edge of water-bodies and waterways, fishing for fish, tadpoles and invertebrates. However, they will also hunt nearby fields and vegetation for whatever terrestrial creatures they can find.

“The skink that this bittern caught was identified as a Common Sun Skink (Mabuya multifasciata), a common species around Singapore, by Dr Leong Tzi Ming. His reason being that the body is bulky, head rather robust and undersides pale white. Kelvin KP Lim agrees with the identification.

“This adds another food item to the Yellow Bittern’s prey menu.”

Note: In the images above, the bittern, after catching the skink, carefully manipulates it so that it can be swallowed head-first. Once the body is swallowed and only the tail is left, the bird needs to stand upright with its neck fully stretched to allow the skink to slide down the throat and into the stomach (below).

Images by Melanie Votaw, ID of skink by Dr Leong Tzi Ming and Kelvin KP Lim.

. .

In early January, Daniel Koh came across a dead Little Heron (Butorides striatus) dangling at the end of a fishing line that got entangled on a branch of a casuarina (Casuarina equisetifolia) tree in Punggol Park.

The dead Little Heron apparently swallowed a fish still attached to a hook at the end of a fishing line. An angler must have carelessly disposed his line with a bait fish still attached to the hook and the bird must have swallowed the fish and subsequently the line got entangled onto the branch. Stuck to the hook and dangling on the line, the poor bird slowly died from starvation.

The pond in the park is a designated fishing area and anglers are always there. This is an example of what can happen if fishing lines are indiscriminately disposed of.

Images by Daniel Koh and Chan Yoke Meng.