Common tree frog (Polypedates leucomystax) at Sungei Buloh Nature Park

WETlands
a publication of Sungei Buloh Nature Park

Vol 6 No 2 Aug 99 Common Tree Frog Otters in Sight Large-Tailed Nightjar Flying Fox (Pteropus scapulatus) Dusky Encounters at Sungei Buloh Weekend Fishing Survey School Activities at Sungei Buloh Spin Doctor at Work: story-telling by the Park		Green for life? Robert Teo has the story of the Common Tree Frog for you Common Tree Frog For the average person, it is hard to believe that there are 25 different species of frogs and toads in Singapore. This does not include the large American Bullfrog commonly sold at restaurants! The only species commonly encountered are most likely the familiar Asian Toad (Bufo melanostictus) and the Banded Bullfrog (Kaloula pulchra), which can be heard bellowing like cattle after a downpour. Do you know that we have four species of tree frogs? In fact, one species is found all over Singapore! If you were to listen and look carefully in gardens and parks, the Common Tree Frog (Polypedates leucomystax) can be easily found. It occurs near freshwater—pond edges, drains, small puddles, where it hides in low vegetation nearby. Sometimes, it can even be found clinging onto the walls of houses, especially near toilets and bathrooms. It is also found here in Sungei Buloh Nature park. The Common Tree Frog is light yellowish-brown, with four rows of dark brown lines or markings along its back. Hence, it is also known as the Four-lined Tree Frog. The underside is either white or light grey. Amazingly, both its coloration and markings can change to blend in with its surroundings. The same frog can appear pale beige without any markings in the daytime and turn a dark brown with blackish stripes at night. This frog is nocturnal, becoming active only at night when it hunts for small insects and other invertebrates. It is also at night when courtship occurs. Male frogs are smaller (37-50 mm) than the females (57-75 mm), and will gather around any standing water to "woo" the opposite sex. The call has been described as a "low-pitched nasal quack". Using its sticky, expanded toe pads, a male will climb up the vegetation and call from one spot until a female locates it. The pair then searches for a spot near water and as they mate, a whitish foam nest is formed and attached to twigs, leaves or walls overhanging the water. The eggs and sperm are released into this foam nest where the tadpoles will form. When the sun rises, the foam nest hardens but within a day or two, or when rain falls, it disintegrates, dispersing the tadpoles into the water below. The tadpole grows to 50 mm and is light brown in colour with irregular darker markings. It has a distinguishing white spot on the head. The voracious tadpoles have mouths armed with strong, black beaks for feeding and are known to be cannibalistic, not hesitating to eat up other tadpoles. In a small puddle, only a single tadpole might be left to develop into a frog—"survival of the fittest" in action. Care to kiss this Frog Prince?
		© Sungei Buloh Nature Park

Vol 6 No 2 Aug 99 Common Tree Frog Otters in Sight Large-Tailed Nightjar Flying Fox (Pteropus scapulatus) Dusky Encounters at Sungei Buloh Weekend Fishing Survey School Activities at Sungei Buloh Spin Doctor at Work: story-telling by the Park		Otters in Sight: Happy Additions Our wish has just been granted. The Smooth Otters (Lutra perspicillata) as reported in the previous issue of Wetlands are not only here but now with a pup too! They were sighted recently by our Senior Ranger and confirmed by our postgraduate researcher. This is indeed good tidings as we were all hoping that they are a courting pair and would bring us more of kind here in the Park. In addition to the Smooth Otters, we have also released some Asian Small-clawed Otters (Anoyx cinera). Treasure the precious moments if you sight these adorable creatures. Take as many pictures as you want ... but please do not feed them or touch them. Leave them in the wild as they should be.
		© Sungei Buloh Nature Park

Vol 6 No 2 Aug 99 Common Tree Frog Otters in Sight Large-Tailed Nightjar Flying Fox (Pteropus scapulatus) Dusky Encounters at Sungei Buloh Weekend Fishing Survey School Activities at Sungei Buloh Spin Doctor at Work: story-telling by the Park		Take a flight into the life of a night flier with Senior Ranger Ramakrishnan RK Journal of a Nature Warden Large-tailed Nightjar *(Caprimulgus macrurus) Bird watching at Sungei Buloh Nature Park would be a more enriching experience if you come across this unique bird, the Large-tailed Nightjar (Caprimulgus* macrurus). It is more often heard than seen, calling from dusk till dawn from its perch. During the day, the Large-tailed Nightjar sits motionless among dead leaves along the sides of paths. The basic colour of its plumage is greyish-brown with buffy underparts lined with numerous black bars. Its plumage blends in with the habitat during the day, keeping it camouflaged from predators and humans. The Nightjar starts to fly after sunset and is active throughout the night. Its "ghost-like" flight is almost similar to the moth's. The characteristic call of a Nightjar—a loud monotonous "chonk" is most often heard when the sky is clear. Feeding takes place during flight when the Nightjar uses its jar-like mouth as a sweep net to catch insects such as moths, large beetles and mosquitoes. The bristles found near the base of the bill suggest that they act as an organ of touch for catching prey. The Nightjar has been observed to breed from March to June. Nest building is not required as the eggs are laid on the ground. The female lays between 1 to 2 elliptical-shaped eggs, which are creamy-white mottled with brown weighing 8-9gms. The first egg is usually heavier and larger. Both parents share incubation duties (16 to 18 days) with the female incubating during the day while the male takes over from dusk until dawn. Nightjar nestlings have down feathers after hatching. Their eyes are fully opened by the second or third day. The nestlings are moved from one spot to another to avoid detection by predators. When disturbed during nesting, the Nightjar flies to a different location and performs a distraction display, flapping on the ground as if it has a broken wing. This art of display is to draw the intruder away from its nest. The nestlings on the other hand will display a flapping of wings with their mouths wide open and lunge forward when threatened. Do try to spot this remarkable bird sitting by the side of the routes on your next visit to the Park. But remember not to pick up any eggs found along the routes as they may belong to this unique bird.
		© Sungei Buloh Nature Park

Vol 6 No 2
Aug 99

Common Tree
Frog

Otters in Sight

Large-Tailed
Nightjar

Flying Fox
(Pteropus scapulatus)

Dusky
Encounters
at Sungei Buloh

Weekend
Fishing Survey

School Activities
at Sungei Buloh

Spin Doctor
at Work:
story-telling
by the Park

Find out more about flying foxes and bats with "Batman" Tay Soon Lian
as he tells you the myths and truths about these amazing creatures ...
in the night, of course...

Flying Fox Scientific name: Pteropus scapulatus Home: Tropical rainforests of Northeastern Australia and Southeast Asian islands. Description: Small, dog-like face and eyes, reddish brown fur, leathery black wings, black nose, wing span of about 5ft, and weighs up to 53oz.

Bat Facts: Unlike their smaller cousins, the bats, flying foxes roost outside in the sun rather than in caves. High above the forest floor, "camps" of flying foxes hang upside down together, sometimes as many as a few thousand will congregate at the same spot. They hang from branches by one or both feet, wrap themselves in their wings and sleep the day away. On very hot days, these bats keep cool by fanning themselves with their wings.

Flying foxes use their excellent sense of sight and smell (more than echolocation) to locate their fruit at night. These creatures are frugivores, i.e., fruit-eaters. They also consume flowers and pollen and assist in pollination in the same way bees do. They use their sensitive sense of smell to detect ripe fruits and places where flowers are blooming. Flying foxes can fly up to 80 km for food! They use their long, bristly tongues (ideal for lapping up juicy fruits) for licking and grooming themselves or their friends. There are more than 160 species of fruit bats in the world, but only about 60 species of the larger fruit bats make up the family of flying foxes. Male flying foxes get the female's attention by singing loudly and flashing bunches of hair on their backs! Obviously the female flying "vixens" think hairy backs are the latest in flying fox fashion apparel!

Now that you know several truths about flying foxes, have you heard these myths about bats?

All bats are blind? All bats can see, see better than us. The larger bats have big eyes that enable them to see flowers and fruits in the night. Smaller bats can still see, but rely on their ability to echolocate in order to capture insects and to navigate in the night.

All bats are dirty and carry rabies? Bats are clean animals that groom themselves daily. Yes, they can contract rabies, but less than 1% of the world's species of bats actually have rabies. You are more likely to contract rabies from an unvaccinated dog or cat.

Bats will try to fly into your hair? Bats do not want to be in your hair! Experiments have shown that they could not get a bat to stay on a person's head even though they wrapped the hair around the bat.

Bats are vampires that will suck your blood? There are only 5 species of vampire bats that live in Central and South America. They do not suck blood. Concentrating primarily on mammals, they make a small incision with their razor sharp teeth and then lap up the blood. Scientists are currently looking into using saliva from these bats to develop new anticoagulant drugs to prevent blood clots in patients with heart-related problems.

However, the one REAL fact I found out from writing about bats is, You Have To Do It At Night!

© Sungei Buloh Nature Park

Behold the magnificent display of the
changing of guards as Adeline Chia guides you along the road of ...

Dusky Encounters

The daily rush to and fro in the course of work has left many of us with little time to stop and appreciate the beauty of nature. Hence when faced with an assignment to find out the life that could be seen before the last rays of sunlight fade away, I was eager enough to finish my work early in the late afternoon for a walk in park. Armed with my binoculars and drinking water, I set off.

It did not take long before I had my first encounter: a Common Sun Skink (Mabuya multifasciata) basking near the main bridge, motionless. Most skinks are terrestrial, making their homes in leaf litter and loose soil. With over thousand species in the world, it is no wonder that they are the most diverse of the lizard family. I admired its rich orange-brown shiny body for a while until it decided that I was getting too close for comfort and went into the bushes, making rustling sounds as it went.

A stream of activities greeted me as I ventured onto Route 1. Most species of birds are diurnal and are unable to feed at night. Once night falls, they have to endure a full 12 hours (in the tropics) of non-feeding through the night until the next dawn when they would be ravenous. With the last opportunity to feed their young and themselves the before the sun sets, you would notice birds engaged in various activities. A Pied Fantail (Rhipidura javanica) darted among the lower branches of the mangrove trees, deftly picking up insects disturbed by its movements. Its eccentric behaviour has earned itself a nickname called the 'gila bird' by the Malays. It feeds in a rather haphazard manner, dashing through the vegetation in a madcap chase with its long tail fanned open and closed, never staying at a spot long enough for the untrained eye to observe it.

As I walked along the trail, Tailorbirds called out to each other, their synchronised calls floating like melodies through the ears. Yellow-vented Bulbuls (Pycnonotus jocosus) cautiously approach their nests with their young, ever on the lookout for predators. Always a joy to see, newly fledged nestlings followed their parents around, ducking into cover at the first call of danger. Monitor lizards lazed on the trails, enjoying the sun-warmed ground.

A family of White-breasted Waterhens (Amaurornis phoenicurus) cautiously crossed the trail into safer territory, the parents ever watchful. A common resident, it is a comical looking bird that usually dives into the undergrowth when it senses danger. Its gait is accompanied with an occasional flick of the tail. When alarmed it will run away clumsily, sometimes with its wings half open into the nearest cover. If you stay motionless,

White-breasted Waterhens

you will find that after a short while a white and black head will emerge from its cover cautiously before taking the first step, then the next and resuming its perky strut.

The flowers of the Sea Hibiscus (Hibiscus tiliaceus) were turning brown, swaying gently with the evening breeze. They have served their function: ensuring the survival of their species. Soon they will fall and in place the seeds of the tree's future generations will be produced.

Reaching the heronry, I was treated to an aerial display of the Grey and Purple Heron (Ardea cinera and Ardea purpurea) returning to their roosts. Beautiful birds they certainly are. Beautiful voices they have not, for their call is a harsh 'Kra-ak'. Some were greeted by their young, hungry for a meal and rewarded with one. Others opted to land on the mudflats to grab a quick meal before returning to their nests which are massive platforms of twigs that sit in the canopy of the mangrove trees. A Black-crowned Night Heron (Nycticorax nycticorax) stood motionless below the canopy with its blood red eyes, its most arresting feature. It is an attractive bird with black, grey and white plumage. One of the few nocturnal birds which is also active at dawn and dusk. Look out for one or groups of them flying over you in the evenings. Can't see them? Listen then to their call in flight which is a monotonous 'kwok'.

Last stop: The freshwater ponds at Route 3. These ponds provide the habitat for freshwater dwelling animals. Peering at the surface of the pond would reward one with the sight of pond skaters and the Two Spot Gouramy (Trichogaster trichopterus), a native species of freshwater fish in Singapore, lingering at the surface. You might bear the occasional splash caused by the Common Snakehead (Channa striata) or Aruan as it is commonly called. Oh, what a big mouth it has, for it is a carnivorous species of fish which can grow up to a length of 90 cm. Valued for its healing properties, it is the fish of choice for post-operation patients who believe that it can speed up recovery of wounds.

Baya Weaver nests

The grasses in the vicinity provide food and shelter for many species of birds such as the Yellow-belied Prinia (Prinia flaviventris), warblers and munias, which were unfortunately not seen this evening. However a male Baya Weaver (Ploceus philippinus) was busy building its nest by weaving strands of long grasses. Masters of nest-building they certainly are, for a Baya Weaver's nest is an ingenious piece of craft, easily surpassing other species of birds in their construction. The male first builds a "helmet" stage nest and displays on it, trying to attract a potential mate. Once a female has inspected the nest and stamps her approval, they mate and the male proceeds to complete the nest which ends with a long tube leading to a side entrance. His partner then lays her eggs and while she is busy with the incubation and caring of the young, the male builds another helmet and tries to attract Mate No. 2.

By the time I made my way back, the sun was all but a dark orange ball in the sky.
From the limited light available I was able to make out the silhouette of a few Large-tailed Nightjars (Caprimulgus macrurus) gliding around hunting for insects. Ah yes, it's another nocturnal bird which sits quietly during the day, their greyish brown plumage providing excellent camouflage against the background.

It was time for animals on the night shift to take over. The world does not rest when the sun sets. Instead a whole new exciting episode begins. Sounds that filled the air during the day are now replaced by others, predominantly the shrilling calls of cicadas, the croaking of frogs and the songs of nocturnal birds. Hence an evening walk is definitely interesting for it is the transition period between day and night, light and dark where you can find the beginnings of nocturnal life and the diminishing of day activities.

Don't be surprised to find bats, the only true flying mammals flying around. When night falls they will be out in full force finding their favourite fruits or insects as they flit about. Slimy creatures such as slugs and snails crawl out in response to the falling temperature and increasing humidity. As soft bodied animals they risk the danger of losing body fluids through evaporation hence a dark, moist environment is perfect for them.

An evening walk is definitely interesting and the Park is open until 7 pm daily, so come on down to experience what the evening has to offer you. As for me, it's time to go for a very important nocturnal activity: Dinner.

© Sungei Buloh Nature Park

Weekend
Fishing Survey

At a nearby pond, the squawking of herons could be heard. A small group of Lesser Tree Ducks glided lazily across a freshwater pond. Baya weavers were busy weaving their unique pendulum nests on a Macaranga heynei tree. Over at two other adjacent ponds, a group of 10 were busy casting lines using rods and hand reels into the tranquil waters. What were they doing?

James Gan gives you an account of
our recent fish survey that documents
the fish life found at our freshwater pond

They were participating in a fish survey during the weekend that included staff of Sungei Buloh, volunteers and staff family members. Unlike the usual fishing practices where the fish end up on dinner plates, the fish that were caught were carefully measured, weighed and released back into the ponds.

Date: 13 May 1999
Time: 1pm to 7pm
Weather: Cool
Location: Route 3 Freshwater Pond

Artificial bait was used and the majority of the fish were caught in this way. A 0.64m Channa striata aka the Common Snakehead weighing 2.5kg was caught after putting up a fierce fight. The rod and line were strained with the weight of the fish, but in the end the skilful angler won. Many "oohs" and "aahs" were heard. Cameras flashed to record the achievement. Not that the other fish were small though—the majority were between 0.4m and 0.5m long.

Park Ranger Charles Lim, hand reeled in a Climbing Perch excitedly while Park Ranger Patricia hooked one on a rod. Other fish caught were Two Spot Gouramies That session saw a total of 24 fish caught on hand reels and rods. Another 30 gouramis were caught with a cast net as were a few unidentified freshwater shrimps.

Through this fishing session, the types and relative numbers of fish that could be caught with various baits and fishing methods in the freshwater ponds of the Park were established.

The survey brought together staff, volunteers and staff family members. Fishing skills were learned or honed. Everyone got to learn another aspect of the Park and the many surprises that it has in store.

© Sungei Buloh Nature Park

School Activities

Evelyn Kuah

Community service took on a different meaning as groups of students from two secondary schools came to Sungei Buloh Nature Park each week to help maintain different areas of the Park and enjoyed themselves at the same time.

Plants are important and keeping them healthy and free from weeds is as meaningful as the planting itself.

Singapore Rhododendron

The girls from Raffles Girls Secondary School learnt about the different kinds of weeds, the before and after effects of clearing the weeds and also about the other plants commonly found infested with weeds, like the Long Grass and the Singapore Rhododendron. Walks to the Main hide and into the Reserve also make their trip to the Park more worthwhile as they see for themselves the birds in flight and the insects and animals they learned in textbooks come alive.

Coastal cleanup and mangrove saplings removal, which are two routine tasks undertaken by Sungei Buloh staff, are new experiences for the upper secondary students of Woodlands Secondary School. They waded in the mangrove mudflats clearing coastal rubbish and pulling out unwanted saplings, and of course, getting a "mud bath" in the process.

There was, however, not a single dull moment each time they came for their three-hour long attachment service. All the girls and boys were briefed on their purpose at the Park and the details of their responsibility for the day. Arming themselves with gloves and insect repellent, they switched into their working mode almost immediately, and soon after, their natural state of enthusiasm overtook the heat, and laughter was all around. The community involvement projects aim to bring Nature closer to the urban kids.

The whole process was a learning experience packaged with fun. With the continued support from the schools and the active participation of the students, this collaboration has turned out to be the beginning of a stronger relationship in future. At the point of writing, an agreement has been reached with Woodlands Secondary School for the adoption of the Butterfly Trail Project at the Park. This is a first step in our effort to have more schools "own" the Park and through the activities inculcate a sense of graciousness while caring for public property.

Spin Doctor
at Work

It was a wonderfully unique experience telling "tales" to young children, as I soon discovered when Sungei Buloh Nature Park was invited for a series of storytelling sessions at our local community libraries during the June vacations.

The natural curiosity of the young ones, spurred by the colourful presentations of the animal life at the Park charged up the atmosphere.

linda goh

The No. 1 hit with kids,
Mr Monitor Lizard

Fuelled with the desire to share the wonders of nature, a "tale" on "Interesting inhabitants of Sungei Buloh" was told to whet their appetite for the real thing. Questions upon questions were exchanged luring us into a discovery channel of animal life. The wonders of nature mirrored evidently in each of the wide-eyed young ones as they eagerly awaited the introduction of each unique creature. Their vivacious attention was soon treated with a dose of cartoon, "A Wetlands Adventure", where they journeyed through the perils in a mangrove swamp. Judging from their warm response, we knew we had hit home the message of respecting animal life and caring for them. This outreach programme was indeed rewarding and one of many future collaborations with the National Library Board.