Saturday, December 24, 2011

Migrating the blog to NSS Kranji Marsh page

Hi all,
I have migrated this blog to the NSS Kranji Marsh page (
Check out for updates.


Tuesday, July 13, 2010

Update of Kranji Reservoir Adoption Programme (May 2010)

By Dr Ho Hua Chew

Pond Maintenance

Maintenance work for the Marshy and Clearwater ponds, at their landward edges and shallower parts, were continued by volunteers. Twenty River Valley High School students came back for a second time on 31 April 2010 to resume the clearing of unwanted vegetation. This was followed by 16 staff from Bloomberg in May 2010.

Bloomberg staff clearing unwanted vegetation from the bund

Apart from voluntary work, professional contract maintenance was also carried out in May at the deeper ends of both ponds. Aside from clearing the unwanted pond vegetation, workers also opened up a clogged stream that flows into the Marshy Pond and cleared the vegetation at the edge of the small bund dividing the two ponds. The cleared plants were sent once again to Green Circle Eco Farm for composting.

Bird Surveys
Three birdlife surveys were carried out in February and March 2010, with the objective of setting up an inventory of the types and numbers of bird species that can be found at the reservoir’s Intake Bund and at the marshland fringe along the Intake Channel. One survey was conducted in the late afternoon while the other two were done in the morning. The transect was along the two kilometer Intake Bund, which is currently under restricted access controlled by PUB. These surveys will provide ecological information relevant to the issue of opening up the Bund on a free-and-easy basis to visitors, hikers, cyclists etc. We are concerned that the establishment of a park connector along the Bund will disrupt the birdlife that are using these areas for resting and feeding. The surveys recorded 39 species numbering 204 birds in all. These include the Little Tern (endangered), Grey Heron (vulnerable), Purple Heron (endangered), Yellow-billed Egret, Yellow Bittern and Yellow Wagtail. At least 17 Grey Herons were regularly using the Bund proper for resting and fish foraging.

Flock of Grey Herons on Kranji Bund by Ian Rickword

Flock of Grey Herons on Kranji Bund by Gerard Francis

A report based on these surveys, as well as information from recent observations outside the surveys, is in the process of being formulated and will be submitted to the relevant authorities by June 2010.

Saturday, May 29, 2010

Kranji Reservoir Adoption Programme Update (April 2010)

By Dr. Ho Hua Chew

Exciting Bird Sightings

After much restoration work to the Kranji Marshes, as part of NSS’ adoption of the Kranji Reservoir, the uncommon Common Moorhen was spotted at the marshy pond on two occasions. Three birds were seen by Leslie Fung on 9 March 2010 and one bird was recorded by myself on 18 March 2010.

Leslie even observed that one of the moorhens was a juvenile. This is good news as the Common Moorhen, which was supposedly common at one time, is hard to come by nowadays. Bird species that were previously not recorded before the restoration are also making a comeback. These include the Yellow-billed or Intermediate Egret, Yellow Wagtail and Von Schrenck’s Bittern.

The best sighting to date is of 2 Cotton Pygmy Goose seen by Lim Kim Seng on 29 January 2010. The one-off appearance of this rare and critically endangered bird is highly significant as it has not been seen for many years. As one of only two wild duck species in Singapore, the Cotton Pygmy Goose may sadly be headed for local extinction. The challenge is to make the Kranji Marshes attractive to them so that they will continue to survive and make regular appearances. We also await the return of the Lesser Whistling Duck.

Cotton Pygmy Goose (or Cotton Teal) & Whistling Duck

Pond Maintenance

Twenty students from River Valley High School were down at the Marshes on 24 March 2010 to lend their muscles in clearing the overgrown vegetation at the marshy pond. Teacher-in-charge Mr Azmi and NSS Vice-President Leong Kwok Peng were there to coordinate the effort. Work began at 3 pm but after about an hour and a half, it began to pour heavily. Students quickly sought refuge in their nearby school bus, which acted as a rain and lightning shelter. Maintenance work resumed the following week on 31 March 2010 from 3 pm to 6 pm.

These helpful students concentrated their efforts in clearing the dry edges of the marshy pond as well as the shallower portions of the water body. The accumulated mass of vegetation was collected by Green Circle Farm’s Evelyn Lim-Eng and her workers for composting.

This is the first volunteer effort in maintenance of the restored marshy pond. Students enjoyed the backbreaking work despite getting soaked, caked in mud, and scratched by thorny Giant Mimosa shrubs. Somebody even had a leech bite! A dab of Tiger Balm was enough to dislodge the bloodsucker. The Conservation Committee would like to thank River Valley High School students for a job well done.

Tuesday, February 16, 2010

Kranji Reservoir Adoption Programme Update

By Dr Ho Hua Chew, Coordinator of Kranji Reservoir Adoption Programme, Conservation Committee

One year has elapsed since the launch of NSS’ Kranji Reservoir (Marsh) Adoption under the PUB’s ABC Waters Programme. Much has transpired during this time and here are some updates:

Kranji Nature Walks
Twelve nature walks at Kranji Marsh were conducted for the whole of 2009. Six of these trips were organized for the public as part of our outreach programme; four walks were conducted for NSS members; the remaining two trips were for corporate and social organizations. All trips had an average of 20 participants. The Education Group also held a “Fun at Kranji Marsh” session for 25 NSS Kids and their parents/caregivers, totaling 70 participants in all.

Pond Restoration and Birdlife
The restoration of the large marshy pond was completed in November 2009, which involved the clearing of unwanted vegetation that had overwhelmed the pond for many years. Now, two thirds of this pond comprises open water free of vegetation, with two small low-lying islands created from the dugged-out mud, which also helped deepen some water stretches. Several fallen tree-branches have been planted at strategic points in the pond to serve as bird perches. The smaller open pond has been left alone for the time being.

The big slabs of concrete lining the main track to the ponds were moved to the site of the Seaside Mempari tree (Milletia pinnata), just by the edge of the pond. These concrete slabs now encircle the tree at a safe distance to prevent soil compaction, serving as seats under the tree’s shade where one can enjoy scenic views of the pond and marshy landscape.

The Red-Wattled Lapwing (4 birds) has made a welcome appearance at the new islands created in the pond. Previously, for many years, these birds have avoided the pond area, restricting themselves to the field of the Mediacorp Transmission Station next door. Also new to the pond is an Intermediate Egret that likes to forage at its far end. The Purple Swamphen and Purple Heron, both of which like to lurk in and around the aquatic vegetation, are now easier to spot. Brown Shrikes and Blue-tailed Bee-eaters have been frequently observed at the marshy pond using the planted branches as vantage perches. This pond restoration will be followed by periodic maintenance to prevent aquatic vegetation from overwhelming the open waters again.

Biodiversity Surveys
Continual monitoring of the types of butterflies, dragonflies and birdlife found at Kranji Marsh are periodically carried out. Prior to the implementation of the pond restoration work, we completed an inventory of the plants, birds, dragonflies and butterflies found in and around the edges of the two ponds. Subsequent monitoring will give us a good picture of the results of the pond restoration work.

Rain-shelter and Eco-toilet
The area chosen to site a rain-shelter and eco-toilet comes under the Singapore Land Authority (SLA). This site is at the entrance to the ponds, close to the Kranji Pumping Station. Approval for the rain-shelter was sought from SLA but was not given. For your information, all dry land at the edges of the two ponds fall under the authority of SLA. We are currently using a bus to act as a rain-cum-lightning shelter, as well as to ferry participants to and from our meeting point at Kranji Reservoir Dam Carpark. This has proven to be highly convenient. At present, there is only one Kranji countryside shuttle service to Neo Tiew Lane 2, but the service starts late at 9 am.

Shrub Planting
Shrubs will soon be planted at the small bund dividing the two ponds, stretching one-third of the way from the back end of the ponds. This exercise is meant to attract butterflies and more bird species to the edges of the two ponds. The Bird, Plant and Butterfly Interest Groups will assist in terms of recommending the various shrub species that can be planted.

The Conservation Committee would like to thank the following people for helping out in the implementation of the Kranji Reservoir Adoption Programme in its various manifestations (nature walks, pond restoration, biodiversity surveys): Leong Kwok Peng, Michelle Sim, Tay Kheng Soon, Stephen Lau, Gloria Seow, Timothy Pwee, Lena Chow, Angie Ng, Gerard Francis, Joseph Lai, Yap Von Bing, Wong Chung Cheong, Anuj Jain, Allan Teo, Margie Hall, Wing Chong, Lim Kim Chuah, Alan Owyong, Willie Foo, Kenneth Kee, Doreen Ang, Peng Ah Huay, Ian and Freda Rickword, Gan Cheong Weei, Simon Chan, Steven Chong, Tang Hung Bun, Cheong Loong Fah.
Note: This article was also published in Nature News Jan-Feb 2010 issue. It can be downloaded from

Thursday, November 5, 2009

Wildflowers of Kranji Marsh

By Gerard Francis

You probably trample on many of these wildflowers without a second thought but look closer and find a world of beauty. Kranji Marsh is a great place to enjoy the wildflowers. Look for them on the grass verges of the road and paths where these low growing plants can get the sun. They climb the trees and shrubs and grow in the ponds. The ones pictured here are common. They are native to our region or were introduced a long time ago and have become widespread and naturalized. Many have found traditional uses as indigenous medicines or foods.

Hedyotis corymbosa, family Rubiaceae

Local name Siku Siku, ixora family. This plant only grows to 30 cm in height. It has really tiny white flowers 3 mm across, in groups of 2 or 4, and the narrow leaves are pointed at both ends. The leaves, or sometimes the roots are used by the Chinese to treat inflammation or to improve blood circulation. In Indian ayurvedic medicine, it is used for a whole range of conditions including fever and jaundice. In western medicine, it is currently being studied for its effectiveness against hepatitis

Cleome rutidosperma, family Capparidaceae

Local name Maman, cat’s whisker family. The family is so called because in some members of this family, the long stamens resemble cats’ whiskers. A very common weed, of African origin. Has very irregular violet flowers with four petals gathered to one side like an insect landing pad, and six stamens hovering over them, to dust the insect with pollen.

Mimosa pigra, family Fabaceae

The Giant Sensitive tree or Catclaw Mimosa, legume family, is from tropical America. Its relative, the more common Mimosa pudica is the low growing, prickly-stemmed touch-me-not we see everywhere. This is the big brother growing to 1.5 m with bigger, pink powderpuff flowers. These filaments are the many stamens. Fruits are dehiscent legume pods. Unlike other legumes which split open at both edges to release their seeds (such as the acacia or flame of the forest), the ripe mimosa pod breaks into a number of small one-seeded segments that attach to animal fur or clothing. This kind of legume is called a loment. Mimosa pigra is listed among the world’s 100 worse invasive species, having spread throughout south east asia and Australia. It can form dense, thorny, impenetrable thickets.

Oxalis barrelieri, family Oxalidaceae

The Lavender Sorrel is from the belimbing family, as is the starfruit, Averrhoea carambola. The pretty flowers just 8 mm across, are at the end of long stalks, with five pale pink or lavender petals, yellow at their base. The fruits are like tiny starfruits that when ripe, split open at a touch to release the red seeds.

Solanum torvum, family Solanaceae

This is the Terong Pipit or Thai Pea Eggplant. Related to our brinjal, Solanum melongena and to the potato, Solanum tuberosum. A hairy-leafed shrub to 1.5m high, the unripe fruit, looking like green peas, are an essential element in thai green curry. The Thais call it makhua phuang. The fruit are slightly bitter, but crunchy and good-flavoured. They turn yellow when fully ripe. Flowers are white and yellow. This useful family, solanaceae also gives us chilli and tomatoes.

Calopogonium mucunoides, family Fabaceae

A climber, with flowers blue-violet, fruit a brown, hairy pod, from tropical America, common in grassland areas. The inflorescence is a slender raceme, bearing 2-6 flowers, each 1 cm across. Used as a ground cover crop in tropical tree plantations and as forage for cattle. Recognized as a valuable pioneer species, because like all legumes, it has the property of fixing nitrogen and improving soil fertility.

Ischaemum muticum, family Poaceae

The Rumput Tembaga Jantan, or Seashore Centipede Grass is wind pollinated like most grasses. With no necessity to attract insects, the flowers are inconspicuous. They grow in a long spike inflorescence and when ripe, the stamens hang out to catch the wind and disperse their pollen, while the stigmas are feathery to catch the pollen. There are 200 species of grasses in the Malay peninsula alone. Economically useful grasses include bamboo, sugar cane and maize. Worldwide, grasses such as rice and wheat, with their rich starchy endosperm supply most of mankind’s food requirements.

Muntingia calaburia, family Tiliaceae

The Buah Cheri has woolly leaves and flowers with five white petals, and prominent yellow stamens that last for only a day. It fruits abundantly all year round bearing edible, sweet red berries. Birds and fruit bats (and small children) eat the fruits. It is also made into jam and cooked into tarts in Brazil, and tea made from the leaves. A pioneer species that thrives in poor soil, the buah cheri is fast growing and bears fruit its first year. A native of Brazil, it is naturalized in south east asia. In the Americas, it is also known as Jamaica cherry, Panama berry and turkey berry.

Polygonum pulchrum, family Polygonaceae

This aquatic plant can be found growing in the ponds, to one metre tall. The inflorescence is a spike-like panicle, densely flowered with tiny white flowers. With a hand lens, you can make out the 5 petals and 5 stamens in each flower. A relative of this plant, the fragrant daun kesom, polygonum odoratum is used in our laksa.

Ludwigia adscendens, family Onagraceae

Commonly known as Primrose-Willow, or Water Purslane. This is another aquatic plant, that floats in the water aided by swollen, pithy floats at the roots, which function like air sacs, and are sometimes called water bananas. The striking flowers have five creamy, white petals, yellow at their base. This plant can colonize a wide area, with propagation even from broken pieces of floating stems. It is used in China for fever and its antiswelling properties.

Tuesday, October 6, 2009

Identifying ferns with Benito Tan

Nature Society members continue to frequent the marsh surveying the pond and the pathway from the barrier at the Kranji farm resort all the way to the pond. But this was no ordinary trip. Angie, Yap Von Bing, his wife Ann and Anuj (me) from the Plant Group were fortunate to have Dr. Benito Tan, a world renowned Bryologist (we call him the 'Moss Man') with us to investigate the ferns around the marsh on 3rd October.

Though it was 1:30pm in the afternoon, it was quite cool after the noon drizzle. There were plenty of plants to check on our way to the pond but we headed straight to the pond to identify the ferns first.

Last week, Gerard (a plant enthusiast and an active NSS member) had spotted an unidentified fern growing on the inaccessible side of the pond (it is lined with wild aquatic plants) so identifying this fern was the most exciting thing planned for this trip. Benito guessed the genus as Cyclosorus but it was hard to confirm the species as the details on the underside of the fronds were barely visible from such a distance (about 10 meters).

Surprisingly the fern seemed to grow only in a small patch on the inaccessible side of the pond. We wanted to see a close up of the fern but this proved difficult due to the muddy pond waters in between and the risk of crocodiles in them.

We thought off a few bright ideas to get close to this peculiar fern species but none of them worked. In the process, we noticed that few other ferns were quite abundant. Most common among them was Stenochlaena palustris (Akar Paku).

Apart from ferns, the pond and the surrounding area also has many other species of plants growing there. We took note of any new species that we had missed documenting earlier. During this survey work, we heard a few bird calls, an eagle calling and even spotted a Purple heron. This bisexual papaya tree at the edge of the pond was doing pretty well. The female flowers are borne along the trunk while the male flowers are borne in long sprays that originate along the trunk.

We went to check the bund area before calling off for the day. Benito was here for the first time so he was pretty fascinated by the CAUTION sign (as you can make out from his photo).

The Moss Man had an idea where else to look for his unidentified fern. Following him along the bund, to our surprise, we found a few patches of the fern - this time growing quite close to the walking path. Indeed! This was quite exciting for all of us. This is Benito’s hand showing us the spores he needed for confirmation. He confirmed it as Cyclosorus gongylodes.

On the way back, we saw an Air Potato plant (Dioschoria Bulbifera) growing wild near the barrier. Seen are the female spikes 10-20cm long. We did not see the male panicles 2-3.5cm long though.

Next to the Air potato was the Pipturus argenteus plant. Angie helped me identify the leafhopper Bythoscopus ferrugineus crawling on its leaf.

The purpose of the trip was fulfilled! There are always new encounters - adding to our increasing list of flora and fauna found at the marsh. This makes it so much fun to go there time and again!

Sunday, September 27, 2009

Pond Restoration - The Heroes at Work

NSS Kranji Reservoir Adoption Committee with the aid of NSS members has rolled up their sleeves quite literally (see the pictures and you will know what I mean). Why? They want to keep the marsh more marshy.

The current indicators like the African tulip tree growing near the PUB station show that the pond is drying up. Put simply, the pond is covered with wild vegetation like Water Bananas (Ludwigia Onagraceae), Water Hyacinth (Eichhornia crassipes), Yellow Burhead (Limnocharis flava) and Simpoh Air (Dillenia suffruticosa). Leaving behind the important patches, the wild vegetation will be carefully cleared to create an open water area conducive to fowl like the Lesser and Wandering Whistling Ducks. The intent is to attract more water birds and preserve the biodiversity of the area.

Works have been on for a few weeks now.

Beating the warm Sun on the morning of 13th September, few Nature Society members – Dr. Hua Chew, Kwok Peng, Allen, Wong Cheong and Anuj (me) were at the marsh to check the progressing work and prepare conducive perches at the pond. Dead branches of strong and durable Acacia wood are ideal for this task. Hopefully they would look naturally positioned in the pond.

We spotted some dead branches in the surrounding woodland but it was no easy task to transport them to the pond since the branches were pretty big. Imagine carrying a few of these for over a kilometer. Tiring isn’t it?

On the way back to the pond, Allen spotted a hornet’s nest on one of the Albizia tree.

We also heard a Greater Coucal (I couldn’t photograph the birds but I saw a pair).
After struggling with the branches, Kwok Peng suggested us to use Hua Chew car as a transport lorry. This saved much energy.

Finally we arrived at the pond.

Adventures are not over yet! Placing these branches in the water was no easy feat again! ‘Roll up your sleeves, fold your pants and prepare to get muddy’. That was the slogan. The more experienced ones lead the way (Dr. Hua Chew & Kwok Peng below).

After some perseverance, the 3 perches were ready for the birds. They look quite natural to me. In the end, I was quite happy with the progress we made.

Perch #1

Perch #2

Perch #3

The next visit to the marsh will tell us whether these perches can stay afloat at the same location. Looking forward for the next visit!