Site Meter

Thursday, March 30, 2006

The Little Heron at the Singapore Botanic Gardens

The Little Heron at the Singapore Botanic Gardens

Azmi Mohamed was at the Singapore Botanical Gardens on the morning of the 26th February 2006 when he came across the Little Heron (Butorides striatus) doing an unusual thing. “It was picking up pieces of bread and dropping the bread into the water. It appeared to be trying to lure fish within range for it to prey on. Most of the time the bread would be eaten by fish too large for it to prey on. Whenever the bread was eaten by a large fish, the bird would pick up another piece of bread and drop it into the water. I didn't observe it catching any small fish successfully.”

Intrigued by the behaviour of this Little Heron, Azmi wanted to know whether anyone else observed this behaviour?

Jeremy Lee reported that he was there the last weekend and saw the same heron standing on a water lily leaf doing the same thing. But it did not manage to catch any small fish.

Robert Teo saw the Little Heron in the company of a White-breasted Waterhen (Amaurornis phoenicurus) and some Lesser Whistling-ducks (Dendrocygna javanica) when visitors came to feed the ducks. But he did not see the bird using bread as bait to fish. Robert wonders whether this behaviour is natural or learned from watching the duck feed.

Hung Bun Tang wrote: ”It is well known that the crows are very clever birds. Little Herons, I have seen in a documentary, may just be as clever. They can bait fish. They observed people feeding ducks in a pond and noticed that fish were also attracted to the bread. So they picked up some tiny bits of bread from the ground and dropped them into water to lure the fish. It worked and they got an easy meal! Sometimes they used tiny insects as baits too.”

According to our bird specialist, R. Subaraj, the Little Heron is indeed using bread as bait to fish. This has been observed a few times before at the Symphony Lake, Singapore Botanic Gardens and several times at the Waterbird Lake, Jurong Bird Park. “This little fellow is certainly not "bird-brained" and I believe the key to success for this little chap is learning where to fish, with bait. At the open areas of the Symphony Lake, the larger fish would take all the bread but in the past, these herons have had more success catching smaller fish by placing it in shallower edges of the pond, usually in shady spots.”

Subaraj further added: “David Attenborough's film crew was keen to film this a few years ago and contacted me but unfortunately the Bird Park's lake was undergoing renovation then and it was not possible.”

Sharon Chan confirms Subaraj’s statement of the happenings at the Jurong Bird Park. She has this to say: “The pelicans and swans are fed on floating platforms. When they feed, some of the food falls into the water. This in turn attracts the attention of the fish. So you tend to see a lot of fish swimming around the floating platforms. When the swans move away, the Little Heron will stand by the edge of the platform staring intently into the water, looking for their food - the fish.

“There is usually a solitary bird at one platform, waiting for its prey. This is not restricted to the herons. The Spot-billed Pelican (Pelecanus philippensis), and Great White Pelican (P. onocrotalus) have taken this one step further. They actually scoop up some food from the tray and drop it into the water to draw the fishes to them. Then they will collectively dip their bills into the water and the fishing begins...”

In the next episode we will look at what Con Foley has to say after he went Googling - looking for information on this intelligent bird.

Contributed by Azmi Mohamed, Jeremy Lee, Robert Teo, Hung Bun Tang, R. Subaraj and Sharon Chan. Images by YC (top) and Azmi (bottom two).


Tuesday, March 28, 2006

Mixed marriages in birds

Mixed marriages in birds

Ilsa Sharp from Perth, Western Australia, wrote on 21st February 2006: “I would like to ask whether anybody has encountered any 'inter-racial marriages' between different species of birds in Singapore, articularly between newcomer aliens and indigenous residents - and if so, are the offspring automatically infertile?

“This thought came to me because I was birding with Birds Australia's Western Australian chapter last weekend, on a bush track following the Swan River in Perth, and our experienced leader introduced us to a cute partnership between a Galah (a pretty pink and grey parrot, Cacatua roseicapilla) and a Corella (white cockatoo-like parrot) of the species (Long-billed – Cacatua tenuirostris) that has invaded Western Australia from Australia's eastern states. He said the birds had been together for 30 years already and had produced young, which were infertile.

“We stood and watched the unlikely pair feeding together on the ground for a while and they did indeed seem devoted to each other! Our leader was not sure which was the male, which the female, though he had seen the larger bird, the Corella, on the nest once.

Just intrigued to know what kind of mingling has been attempted in Singapore, if any.”

Our bird specialist, R. Subaraj replied: “Your Cockatoo mixed species pairing is most interesting. Particularly since the Galah is not an uncommon bird there and he/she should not have been short of partners.

“The current wave of thought in South-West Australia is that all birds of the three species of corella around Perth (Little, Long-billed and Western) are feral (originate from escapees). The natural populations of the first two species don't come anywhere close to western Australia while the Western may have been native around Perth in the past but went extinct, so the current birds are considered feral. The native population is supposed to be further north of Perth. At least this is what I have read.

“If this is true, then the Long-billed Corella in the mixed pair may not have had a mate of the same species 30 years ago and paired off with the Galah.

“All reports that I have heard of with regards to mixed species pairing have the offspring being infertile. If they are fertile, then the two species involved must be subspecies rather than species.

“In Singapore, there have been records of Common/Javan Myna offspring with the bird being grey with a yellow eye-patch (Kang Nee pers. comm.). However, I cannot recall other strange pairings involving native species. At present, a lone female Rhinoceros Hornbill (Buceros rhinoceros), who has been at Bukit Timah for more than a year, has apparently found a partner in the form of a female Great Hornbill (B. bicornis)... and they have been seen prospecting potential nest holes around Hindhede Quarry!”

Contributed by Ilsa Sharp and R. Subaraj. Top image of Tanimbar Corella and bottom of Rhinoceros and Great Hornbills by YC

Ilsa wrote on 25th April 2006: "Remember that posting I made earlier regarding 'mixed marriages' among birds - my original observation being the longterm relationship between a Galah and a Corella cockatoo in Western Australia? Well, sorry for the long lapse in time, but I have now got a photo of the happy couple, attached! For those who don't know, the Galah is the pink and grey one, pretty but there are suspicions that the big white Corella may actually be the female! Thanks to WA birder Ted Cawley for the photo. Ilsa, Perth, Western Australia


Monday, March 27, 2006

Little Grebe: Going out with a fight

Little Grebe: Going out with a fight

"On December 12th, 2005, as I was leading my American clients on a birding tour at Serangoon (Sewage Works), we stopped to observe an adult Little Grebe (Tachybaptus ruficollis). Suddenly, another adult swam into view with two juveniles in tow, much to my excitement. There has been only three adult grebes left here and so it was quite unexpected to find that they had bred.

"The Little Grebe first arrived in 1992, at a little pond adjacent to the old Ponggol pig farms. By 1994, there were a few feeding and breeding across the Serangoon River, at a large pond, at the Serangoon Sewage Works. Colonisation from nearby Malaysia was a success and the grebe population continued to grow with a high count of 27 birds in 1996.

"Soon after, the large pond was filled in and although a shallow pool emerged from the original site, the only good pond that remained was the smaller pond. This pond continues to exist and holds the last remnants of the Little Grebe population. This had dwindled to just three birds in the last two years.

"The grebe makes a floating nest of water plants in the middle of the pond and it has bred a few times before, especially when the larger pond was around. The small remaining population still built nests but in many cases, these were not utilised. That is until this year. A nest was built in the middle of the pond and an adult sat on it. Even this behaviour did not mean nesting.

"The only record of a Little Grebe away from the Serangoon/Ponggol area was of one bird at the Tuas grassland. Why is the species not found at Sungei Buloh and other wetlands areas? One likely reason is the presence of the large predatory Common Snakehead or Aruan.

"So, is the Little Grebe to have a very short stint as a Permanent Resident?

Regards, R. Subaraj."

Contributed by our bird specialist R. Subaraj. Image of nesting Little Grebes taken with permission from Ong Kiem Sian's video Precious Moments of Nesting Birds I.

PS 1: On 27th March 2006 Ong Kiem Sian wrote in: "I saw once a family of grebes with 2 chicks at Tampines pond. I have not been there for many years. Maybe the pond does not exist anymore."

PS 2: Alvin Wong from Beijing wrote on 11th April 2006: "Howdy folks, I'm currently in Beijing, China (where blogspot is blocked and I cannot post my comment on besgroup). I used to observe Little Grebes swimming in the water-logged empty land across my block in Punggol. now it's a cluster of HDB flats under construction. Bird-watching from my living room..."


Saturday, March 25, 2006

Hornbill Project Singapore

Hornbill Project Singapore

The Hornbill Project Singapore is the brainchild of French naturalist, Marc Cremades of the Winged Migration fame. The ides came two years ago when he visited Pulau Ubin with long-time local birder, Prof Ng Soon Chye.

Much is known about these large and wonderful birds but relatively little is known about the breeding behaviour. We know that the female is confined inside a tree cavity during egg incubation and the development of the nestlings. During this 6-7 weeks, the male bird regularly and faithfully brings food to feed his mate and later the nestlings as well. Only when the nestlings are ready to fledge will the seal be broken. However, next to nothing is known what happens inside the sealed nest.

The project is using infrared video cameras to monitor activities inside and outside the nests. Male birds will be tagged with a miniaturised GPS to track their movements. A temperature gauge placed inside the nest will study the temperature fluctuations. A gas sampling system has also been installed in the nest cavity.

So far, five females have already been installed inside their nest cavities and at least one has laid a clutch of eggs. The project has found that as soon as the female is installed inside the nest, she sheds her rectrix and remex feathers.

Local partners of the project include National Parks Board, Jurong Bird Park, National University of Singapore, National Technological University and the BESGroup of the Nature Society (Singapore). International partners include ornithologists and scientists from France and Thailand.

As the Bird Ecology Study Group is directly involved in this hornbill project, we are monitoring sightings of these birds on mainland Singapore. Information on dates; number of birds; whether male, female or juvenile; locations and time of sightings can be sent to me at This information would come in useful when we plot the flight range of these hornbills.

We are grateful to the many who have sent in sightings on the Oriental Pied Hornbills (Anthracoceros albirostris convexus)as well as the Great (Buceros bicornis) and Rhinoceros (B. rhinoceros) Hornbills.

Read the more detailed account of the project in the latest issue of Asian Geographic (No. 35 Issue 2/2006).

Image comes from the title page of the hornbill article in Asian Geographic.

Labels: ,

Thursday, March 23, 2006

A Great Hornbill came for a visit

A Great Hornbill came for a visit

We regularly see the Oriental Pied Hornbill (Anthracoceros malayanus) in mainland Singapore and in Pulau Ubin. But Stephen Lau had a treat when a Great Hornbill (Buceros bicornis) came for a visit at his condomonium around the Bukit Timah area.

One morning in May 2005, just as Stephen was about to leave his apartment for an appointment, he heard the heavy falpping of wings and deep harsh sounds coming from his balcony. Curious, he went to investigate. He had a treat of his life when he saw perching comfortably on the railing, a very large black and white bird with a yellow neck and black-rimmed red eyes. It had a large and prominent yellowish bill and casque. Without doubt it was a hornbill. In fact it is no ordinary hornbill. It was a female Great Hornbill, definitely an escapee as a metal tag can clearly be seen round its right leg.

It sat there looking at Stephen and started chewing and spitting seeds of some fruits kept hidden in its big beak. Intrigued, he offered the bird a slice of papaya on a plate. The bird scrambled off to his neighbour's unit but returned later to finish off the piece of papaya.

Input and image by Stephen Lau.


Wednesday, March 22, 2006

Forensic birding 3: Pellets

Forensic birding 3: Pellets

A few weeks ago I picked up a small, 14 x 14 mm piece of dry, compressed pellet on my driveway. On examining it under the hand lens, I found that it was composed of short pieces of fibres, a few sand grains, pieces of what looked like coloured palm fruit skin and other unidentified materials.

My immediate conclusion was that it must have been regurgitated by a bird perched on an overhanging ceram palm (Rhopaloblaste ceramica) frond.

Could it actually be a pellet regurgitated by a bird? My knowledge of pellets then was confined to those compressed, undigested bones, hairs, feathers, etc that owls and other raptors regularly regurgitate. But then, pellet casting by non-raptors? By insectivorous birds? By frugivorous birds even?

Intrigued, I looked up the literature. Yes, the literature is flooded with reports on pellet casting by raptors. However, there are also a number of reports of pellet casting by birds that regularly consume fish, insects, caterpillars, etc.

Now, why do birds that are not birds of prey need to cast pellets? Fish-eating birds swallow bones that are removed as pellets. Among the contents of these pellets can be found otoliths, those hard inner-ear bones that can help identify the species of fish consumed. Insect-eating birds need to spit out the hairs of caterpillars and the exoskeletons of insects, for example.

When a bird takes in its food, this is normally passed directly down into the stomach. Here, enzymes, acids and mucous are produced and the process of digestion begins. The food is then passed on to the second part of the stomach, the gizzard, where the soluble parts are ground and passed through to the intestines. The indigestible part of the food is compressed into a pellet by the gizzard, thus taking the shape of the gizzard. This pellet will eventually be regurgitated.

Local birders are familiar with pellets regurgitated by raptors. But most are unfamiliar with pellet casting by other birds. But this is a common occurrence in many groups of birds. In fact the International Bird Pellet Study Group listed 18 orders comprising 67 families and 316 species of birds that indulge in pellet casting. And this was as far back as 1979. Birds that cast pellets include crows, cowbirds, grackles, cormorants, grebes, gulls, terns, swallows, sanderlings and rails.

My only encounter with pellet casting was when I tried to photograph a Blue-tailed Bee-eater (Merops philippinus) perched on my neighbour’s TV aerial. The bird suddenly opened its beak and made some sort of retching action. It must have regurgitated a pellet. As the bird eats mainly insects, the pellet must have been made up mainly of insects’ exoskeletons composed on indigestible chitin. Like scats, you can tell what the birds have been eating by examining their pellets.

Now coming back to the pellet I picked up. I am still wondering what bird spitted it out? And whether it was an insect-eater or a fruit-eater?

Text and image by YC, scale in mm.

Latest: After the above was posted, we received a note from Cheong Weng Chun who wrote: "Yes, non-raptors do regurgitate. I only know about this a few months ago when two nature photographers stumbled upon a bee-eater with its beak open wide and suddenly a pellet dropped out. They even sent me a sample of the pellet. However, due to my busy schedule at work and the heat inside my car (yes, I kept it inside my car for a couple of days), it was subsequently smashed accidently. But yes, I did see the exoskeleton of insects especially wing parts."

We also received from Jianzhong Liu an image of a Blue-tailed Bee-eater regurgitating a pellet, an act he saw a few times and was lucky to get a shot of it. The image is reproduced below.

Thank you Weng Chun and Jianzhong for your feedback.


Monday, March 20, 2006

The cat and the Cinnamon Bittern

The cat and the Cinnamon Bittern

Seiko Okajima reported an early morning intruder to her house at Opera Estate in February 2006 thus: “My cat brought in this bird to my house early this morning around 1:00am of Feb 3, 2006. This young bird was not harmed and later flew away safely, but lost some feathers taken by my cat. My house is in Opera Estate off Siglap Road. I've never seen this kind of bird near my house during the day.”

Our bird specialist, R. Subaraj, has this to say: “The bird in the photos is a Cinnamon Bittern (Ixobrychus cinnamomeus). The species is normally found in wetland areas such as flooded fields and marshland. While a small number are resident in Singapore, it is believed that many occur as migrants from northern Asia. During the passage months, when the birds are undergoing migration, different species of migrants turn up at the strangest places, including buildings and homes, probably due to disorientation caused by the bright lights of urban areas.

“As Opera Estate is a suburban area, quite away from the nearest marshy area, this individual is probably a migrant that was undertaking a nocturnal movement (most migrants travel by night). For future reference, it would be a good idea to house such migrants for the night and release them during daylight at the nearest marshland/wetland area. This will minimise the risk of the bird getting further disorientated by the lights at your estate and allow the bird to feed in suitable habitat to recover from both the distant movement and the cat attack before continuing it's travels the next night or so."

Input by Seiko Okajima and R. Subaraj, images by Seiko.

After the above account was posted, Hung Bun Tang sent in the image of a dead Cinnamon Bittern (below) he found near Malcolm Park in the early morning of 9th January this year. He also believes that this species may be more prone to disorientation during nocturnal flights, thus becoming easy victims to attacks by predators. Thanks, Tang.


Saturday, March 18, 2006

Oriental Pied Hornbills in urban Singapore

Oriental Pied Hornbills in urban Singapore

Once upon a time, there were three species of hornbills present in Singapore. However, due to rapid development and large-scale deforestation, all three species became extinct in the late 19th century.

One species, the Oriental Pied Hornbill (Anthracoceros albirostris convexus), has made a comeback. There are many of this bird in the offshore island of Pulau Ubin. The original nucleus probably arrived years ago from nearby Johor, Malaysia. On mainland Singapore they are also present, probably originating from a pair of escapees. These birds have now established themselves and are actively breeding.

Many sightings have been reported from mainland Singapore during the last few years, from areas around Kent Ridge, Bukit Timah, Sembawang, Seletar, etc. They often visit urban gardens, foraging for fruits like rambutans and figs. In most cases the birds were shy, flying off when approached.

This year alone there have been a number of sightings. In January, Fuhai Heng saw a family group comprising father, mother and a juvenile in Sembawang. In February, Johnny Wee encountered one feasting on rambutan fruits in Yio Chu Kang Gardens. And Angie Ng saw her pair in an angsana tree (Pterocarpus indicus) next to Changi Meridian Hotel. Similarly Goh Si Guim encountered a pair during his nature walk, examining a cavity in a pulai tree (Alstonia sp.). This pair was obviously looking for a sutitable nesting hole. Also in February, Vilma d’Rozario’s colleague Angelia spotted one flying across the Pan Island Expressway, along that stretch between Eng Neo and Bukit Timah exits. James Heng similarly saw a bird in Upper Seletar Reservoir.

Reporting from Binjai Park, Marisa Keller wrote in saying that the bird was commonly seen around her neighbourhood. She first sighted two birds in July 2005, some juveniles on 15th October and three birds on 30th October. Marisa says: "In the 13 years I live here I never saw or heard a Pied Hornbill."

Our bird specialist R. Subaraj has this to say: “There have been several hornbill sightings, of various species, over the years and from various parts of Singapore. While all are regarded as escapees, we cannot be entirely certain that we do not receive strays from Malaysia. Based on the locations of the above reports, it may be that most were Oriental Pied Hornbills as three have been seen off and on at the Bukit Tinggi/Binjai Park area. These may be part of a feral population that started years ago at Upper Seletar Reservoir. The other possibilities are Great Hornbill (Buceros bicronis) or Rhinoceros Hornbill (B. rhinoceros), as there appears to be one of each at the Bukit Timah Nature Reserve."

Hornbills are still around in Singapore. So the next time you see a large black and white bird with a large and prominent beak flapping noisily about, chances are that the bird is a hornbill.

Input by Fuhai Heng, Goh Si Guim, James Heng, Vilma D'Rozario, Johnny Wee, Marisa Keller and R Subaraj. Images from top down: YC, Johnny Wee, Fuhai Heng and Marisa Keller.


Thursday, March 16, 2006

Pink-necked Green Pigeons 4: The birds have flown the nest

Pink-necked Green Pigeons 4: The birds have flown the nest

The following information comes from observations conducted in February 2005 on a nesting pair of Pink-necked Green Pigeons (Treron vernans) in my garden (see 1 and 2). It is reported here to provide conclusion to the series.

Egg incubation took 17 days. The newly hatched nestling was near-naked, sparsely covered with short pin feathers. The two large and prominent eyes were closed. As with the eyes, the large beak was similarly out of proportion to the body. On the second day, more pin feathers sprouted, as well as the beginning of black primary feathers and a few yellow ones. On day three the eyes were opened and on day six the nestling was totally covered with feathers. A day later the nestling was observed to actively preen its feathers and exercising its wings. The nestling was restless, moving around the nest while the parent bird sat quietly still.

As in egg incubation (see 3), the male looked after the nestling during the day and the female during the night. Both parents helped feed the nestling.

As the nestling grew older, it exercised its wings by flapping them, especially when the wind blew through the tree. The nestling fledged at 10 days, leaving the nest to eventually find it way to a nearby mempat tree (Cratoxylum formosum). The male parent was seen sitting beside the fledgling, feeding it whenever the latter begged by pecking its parent’s neck. Sometimes the fledgling used its wing to harassed the parent bird for food. According to the literature the fledgling is fed with regurgitated fruits, not crop milk.

The pair remained on the same branch until evening. The next morning the male bird was still at it side. The female must have left early. By late afternoon the male bird left the fledgling alone before the arrival of the female. Some evenings both parent birds would vocalize, cooing and making rasping sounds as well as flapping their tails. The fledgling would suddenly appear from hiding and all three would fly off. Whether the fledgling was left along during the day or the male was accompanying it, I am unable to say. Similarly I am ot able to say what happened during the night.

With each day the birds would fly further and further away from the nesting area, no doubt until the fledgling totally mastered its ability to fly.

In all, I had been observing these birds for nearly a month, All the time, while the birds were in the nest, I was keeping close watch behind a canvas hide twice a day to record the shift change. Naturally when they all left the scene I was left with an empty feeling – to await the next time a pair nest in the tree again.

Note: Birds' nests and the birds in them should not be disturbed unnecessarily, otherwise there is always the possibility of the parent birds suddenly abandoning the nestlings.

For a complete account, please see: Wee Y.C. (2005). Forging a closer relationship with Pink-necked Green-pigeons. Nature Watch 13(3): 16-21.


Tuesday, March 14, 2006

In and out of the Yellow-vented Bulbul's nest

In and out of the Yellow-vented Bulbul's nest

On 10th February 2006, five days before the writing of this entry, my parents noticed movements in our small chiku tree (Manilkara zapota). This tree is no more than 2 metres tall and is right next to the fence that separates my neighbour's garden from mine.

In my mother’s words: " An olive bird with a dark ring around its eyes with twigs in its beak was hopping from branch to branch." There were two birds, identified as a pair of Yellow-vented Bulbul (Pycnonotus goiavier). Within an hour or so, a small cup of twigs came into shape. The bird would often sit in its nest, while arranging and weaving new-found twigs into the cup around it. They were done by the end of the day after repeated returns to the nest with more nesting materials.

The nest was built with a variety of twigs, some coarser, some finer. But what struck me was the unusual white substance that formed part of the cup (see left). Apparently, it was a small piece of fabric that was incorporated into the nest.

The nest was well camouflaged but had only one weakness. It could be viewed easily from the side due to an opening in the chiku tree foliage. As such, the bulbuls, whenever they were at the nest, would often fly off the moment they saw anyone approach from that side.

I also noticed that they entered the nest from various points to avoid detection. One entry was by way of the fence. By landing on the fence that was beside the tree, the birds had easy access to the nest - just two hops away. Another was from the bottom of the foliage, and by hopping from branch to branch, it could reach the nest at the top. Thus the birds would not be flying in from the top and be noticed. This is quite similar to the strategy adopted by the Greater Coucal (Centropus sinensis) that walks till it reaches the nesting site, then fly up, rather than fly in straight.

A day after the nest was completed the birds were rarely there. Whenever they returned, they would bring more materials, to continue touching up the nest. After they were truly satisfied with the nest, they still did not frequent it and were often seen on my neighbour's roof making alarm calls. This could be because they noticed me watching them.

However, they returned nearer to the nest in the mornings and evenings. Perching on the fence and making excited calls, raising and lowering their heads as they did so.

I have no idea whether these bulbuls would lay eggs as there have been a lot of interference from my immediate neighbour and from my parents who tended the garden, usually resulting in the bulbuls leaving for long periods at a time.

Contributed by Lim Junying with images supplied by him, 15th February 2006.

PS: After 12 days of incubation, the parents failed to return the next day. I assume it was either a bad egg or the egg was taken by a lizard or cat. JY Lim, 25th March 2006.


Sunday, March 12, 2006

How sunbirds harvest nectar from flowers

How sunbirds harvest nectar from flowers

Sunbirds are among the most attractive birds around, especially the males. The females on the other hand are rather drab. The food of sunbirds is largely nectar, taken off a wide range of flowers, both native and exotic. In the case of exotic flowers, when the birds are not able to reach the extra long corolla tube, they tend to puncture the base of the corolla to obtain the nectar direct.

Most sunbirds have slender, curved bills whose tongues are long and just as slender, often projecting way out beyond the tip of the bill (see above). But have you ever wonder how these birds harvest the nectar from the flowers?

Well, the tongue of most sunbirds is a closed tube along the major part of its length. This tube is formed by the inward rolling of the edges to meet at the top, thus effectively giving the bird a straw with which to suck up the nectar. The tip of the tongue is usually split and bi-tubular.

Thus when the bird pokes its bill into the corolla tube of the flower and extends its tongue, the straw-like tip will automatically take up some of the nectar through capillary action.

Input and images of male Olive-backed Sunbird (Nectarinia jugularis) (top) and male Crimson Sunbird (Aethopyga siparaja) (bottom) by YC.


Friday, March 10, 2006

Mistletoes 5: Germination of Macrosolen cochinchinensis

Mistletoes 5: Germination of Macrosolen cochinchinensis

A Macrosolen cochinchinensis seed, when deposited on to the branch of a host plant by a bird, germinates by growing a green stalk with a disc-like tip. This stalk elongates, arching back to send its disc-like tip fusing into the stem of the host plant to become the haustorium. When the haustorium is firmly attached, the seed is lifted off, the seed coat shrivels and drops off to reveal the first pair of leaves, the cotyledons! The shoot then elongates, giving rise to further pairs of leaves.

Note: This plant is a tropical mistletoe, a semi-parasite that grows on the branches of many wayside trees and ornamental plants. Please see our earlier postings on the plants, seeds and germination and accounts by a naturalist and a sometime bird watcher.

Text and images by Angie Ng


Wednesday, March 08, 2006

Ground foraging by a Malkoha

Ground foraging by a Malkoha

On February 7th 2006, as we were conducting a recce trip at Sarimbun, Robert Teo, Robin and I came across a party of three Chestnut-bellied Malkohas (Phaenicophaeus sumatranus) in the secondary forest. The encounter was surprising enough as there are no prior records from this part of Singapore.

The Chestnut-bellied Malkoha is the last surviving species of malkoha in Singapore. The resident population is confined to the central nature reserves of Bukit Timah and the Central Catchment with the odd records from the fringe areas of Bukit Batok Nature Park, Bukit Tinggi and Upper Thomson Road. A record from Pulau Ubin by Robert Teo probably refers to a visitor from nearby Johor. In Malaysia, this species of malkoha resides in lowland rainforest, riverine forest, coastal forest and mangrove forest.

As there were three birds present at Sarimbun, it remains uncertain whether these birds are resident or merely visitors from the nearby coastal mangrove belt in Johor. The birds were fairly confiding, allowing close observation for 15 minutes or so, as they foraged in the middle and upper storeys of the trees around.

Suddenly, one bird flew down to the ground and was observed foraging on the ground, amongst the leaf litter. It made short hops as it searched for whatever was about without success. Soon, it hopped up to some low branches before flying up into the crown of the nearest tree. The malkoha is largely an insectivore and hunts for invertebrates among the branches of forest trees and bushes.

I do not recall seeing a malkoha (certainly not this species) foraging on the ground before, despite numerous encounters over the years, both here and in Malaysia. Has anyone witness this behaviour from a malkoha before?

Contributed by Subaraj Rajathurai.

This bird feeds mainly on locusts, mantids, stick insects, leaf insects, cicadas, crickets, grasshoppers, large hairy caterpillars and sometimes even frogs and lizards. It also eats fruits and seeds. The bird in the picture, courtesy of KC Tsang, has in its beak a katydid, a green long-horned grasshopper. YC


Tuesday, March 07, 2006

BESGroup Forum

BESGroup Forum

The Bird Ecology Study Group has set up a BESGroup FORUM for members to post topics, comments, etc. Viewers are welcome to join by clicking the link above or that in the white box on the lower right of the screen and simply register. By joining and actively participating, we hope to enhance the forum quality and participation. Only by sharing can we not only hope to increase our knowledge of the birds around us but also to expand our understanding of bird behaviour and ecology.

Most, if not nearly all of us, are not practising ornithologists. As amateur birders, we would have a superficial knowledge of the birds flying around. There would be some who can claim to be familiar with most of Singapore's birds. Well and good. But to be able to ID the birds does not mean that we know them.

KC Tsang, a long time experienced birder, only yesterday posted to the group the now-famous quote of the American Physicist and Nobel Laureate, Richard Feynman (1918-1988):

"You can know the name of a bird in all the languages of the world, but when you're finished, you'll know absolutely nothing whatever about the bird... So let's look at the bird and see what it's doing - that's what counts. I learned very early the difference between knowing the name of something and knowing something."

BESGroup hopes to strive to first know the name of the bird, then to actually get to know the bird. Only with the help of interested birders who report back their observations by posting in the forum, and ultimately in the blog, can we achieve our aim.

We posted the seemingly simple observation of Interspecific Interaction of Birds at Pasir Ris on 20th February 2006 by Lin Junying, a young birder. This attracted the attention of Mike, a seasoned American birder who runs 10,000 Birds to comment: "Very perceptive post! This really underscores the difference between looking at birds and really watching them."

What more can we say?



Monday, March 06, 2006

The noni tree

The noni tree

I have a pair of slender-stemmed mengkudu (Morinda cirtifolia) growing by my gate along the driveway. The plant grows wild throughout Southeast Asia, having been introduced from Queensland, Australia a very long time ago. Now the Malay name is not as well known, replaced by the up-market name of noni. This is because some enterprising person decided that the fruits have all sorts of health-giving properties. And started marketing the juice as a health product.

The pair of 3-metres tall trees must have been brought there in the form of seeds by a bird. They are continuously flowering and fruiting profusely. The flowers are regularly visited by a variety of insects for their nectar. Flies and bees are always around. A few butterflies like the Palm Bob (Suastus gremius gremius) and Lemon Emigrant (Catopsilia pomona alcmeone) are regular visitors.

Daily one or more male Crimson Sunbirds (Aethopyga siparaja) visit the flowers for the nectar. I am sure there is also a female around but the male is so much prominent and attractive with his crimson colouration. They announce their presence by their high pitch chit, chit, chew sound they make. These smallish birds do not stay long at one spot for a proper photographic shot but move rapidly from flower to flower all the time. And before you know it they have departed for another plant elsewhere.

Sunbirds also visit just after rain. They come and have a series of quick baths using the droplets that collect on the surface of the large leaves, see Bathing Sunbirds.

The ripe fruits litter the ground below. I have been told that in Hawaii, dogs love these fruits, growing fat on them. I am sure our local dogs eat them also, if given the opportunity. So far, I have seen two species of birds relish these rancid smelling fruits. Pairs of Javan Mynas (Acridotheres javanicus) will approach the ripe fruit lying on the ground, take a quick peck and retreat before coming again for another beak-full. Yellow-vented Bulbuls (Pycnonotus goiavier) similarly eat the fruits, but only when the mynas are not around.

On 24th December 2005 I was surprised to see a pair of these bulbuls making a ritual of eating the fruit. The pair was dancing around the fruit lying on the ground, tails flapping up and down and at regular intervals taking pecks from the fruit. It is interesting to note that these ripe fruits are never totally eaten, three quarters would always be left behind.

It would be interesting to receive feedback on what other birds go for these fruits.

Text and images by YC. Steven Chong assisted in identifying the butterflies.


Saturday, March 04, 2006

Why do parrots use their left feet to handle food?

Why do parrots use their left feet to handle food?

The Family Psittacidae incorporates the parrots, to which the parakeets also belong. These birds are characterized, in many cases, by their colourful plumage, prominent curved beak and short legs. They have zygodactylous feet in that of the four toes, digits 2 and 3 point forwards and digits 1 and 4 point backwards. Such a foot pattern is well suited for grasping branches and moving along the branch. Parrots thus move sideways in slow and deliberate steps, their feet often turning inwards, grasping the branch and moving along.

The antics of the Long-tailed Parakeets (Psittacula longicauda) eating rambutans (Nephelium lappaceum) (top), or attacking oil palm fruits (Elaeis guineensis) (bottom) at the Singapore Botanic Gardens’ Visitors Centre, are amusing to watch. Their feet and beak are very manipulative. The fruit is first wrenched free from the bunch with the help of the bird’s beak. Standing on one foot, the fruit is transferred to the other foot, usually the left foot. The left foot is then raised while the beak is lowered so that they both meet half way. With the help of the powerful beak, the flesh of the rambutan or the oil-rich fibrous outer layer of the oil palm fruit is torn off.

This zygodactylous feet also enable the Blue-crowned Hanging Parrot (Loriculus galgulus) to hang upside down to reach otherwise inaccessible fruits or flowers. It detaches an item and perching on one foot, transfers it to the other foot, again usually the left, which is held up to the beak for ease of access. As in the case of the parakeet, the beak is lowered and the foot is raised to meet each other half way.

Now we return to the question of why parrots use their left feet to handle food. Frankly I have no idea! Do you?

Contribution and images by YC.


Thursday, March 02, 2006

Forensic Birding 2: Bird scats

Forensic Birding 2: Bird scats

After forensic birding was first introduced to local birders in December 2005, a workshop subsequently conducted by "sometime" field ornithologist Wang Luan Keng (above, right) exposed us to its practical side. In addition to feathers, skeleton parts, eggs, etc., we looked at bird scats that are found on the ground (this we usually ignore), on the car windscreen (this we notice) and sometimes on ourselves (this we try to avoid). So we take bird scats for granted until they land on us.

However, it is useful to know their characteristics and be able to identify them. After all, when we see the scats, the birds are usually not around anymore. But how many of us are able to do so? If we are interested to know the bird better, we should also make an effort to know its poo too.

What are the characteristics of the scat? What can we find in the mess on the ground or the car? The shape of the scat can be telling! Whether ants gather for a feast, indicating the presence of sweetish matters? Then there is the white uric acid that most birds excrete. Also the presence of seeds, giving a clue as to what the bird has been eating. Indeed, we can tell much about the bird by examining the scat.

Luan Keng hopes to collect information on these scats. She has asked me to watch birds, especially when they poo and send her images of the scats. But she has specifically asked not to be send the genuine stuff.

So the next time you come across a scat, make a record of it and try ID the mess. Then pass it around for an interesting discussion.

Images of Pink-necked Green Pigeon's scat and workshop by YC.


Site Meter Amfibi Directory Singapore Blogger Organisation