This document is endorsed by the Executive Committee & Council of the Nature
Society (Singapore.)
We understand that the Resorts World’s plan for the Sentosa Integrated Resort involves the use of the coastal forest north of Siloso Road. It appears to us that the forest is already being prepared to be cleaned up --- with only selected trees that are mature and of botanical interest to be left standing. This will convert the area from a self-sustaining forest to a parkland, which will be clean and neat but requiring a high degree of maintenance. It is not clear what the actual usage for the area is going to be but whatever is the plan to be finalized, we strongly urged that the forest be left as it is as a forest eco-system. Apart from alien species, the cutting and clearing of the undergrowth and any plants that have grown naturally over the area leaving only the old, tall or interesting specimens standing will constitute a destruction of the forest ecosystem.
The reasons for our stand are spelled out below:
1) The forest cover on Sentosa has been eroded over the decades with the opening and development of the island for recreational uses (the creation of the two golf courses, hotels and resorts, etc). Given the situation right now, there are only three more or less compact forest patches left on the island and these
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amounts to a total of 52.4 ha, which comes to about 15 % of Sentosa’s original total land area (i.e. minus the reclaimed land.) These patches (area sizes given by SDC) are: a) Around Mt. Serapong (31 ha) a) Around Mt. Imbiah (14.8 ha ; inclusive of the 2.9 ha. northern & the 2.4 ha. southern coastal stretch) c) Around Mt Siloso (6.6 ha)
The rest of the tree-cover on the island are merely very small degraded patches of woodlands scattered here and there --- with mostly planted trees. The northern coastal forest at issue here comes to 2.9 ha. --- which comes to about 20% of the
Mt Imbiah cluster (14.8 ha) and 6% of the island’s total forest cover (52.4 ha).
This is a significant chunk for the Imbiah cluster and also for the whole island --- given the very humble total acreage.
The forest cover on Sentosa is part of a remaining cluster or chain of secondary forest on our Southern Ridges (at Labrador, Mt Faber, Telok Blangah, Kent
Ridge, etc.) Because of the relentless developments along Singapore’s southern sector, these forests have already dwindled drastically and efforts should be committed to preserve whatever chunks that remain.
2) The opening up and development of the northern coastal forest (north of
Siloso Road) will destroy an indispensable buffer to the Imbiah Forest, leading to further edge-effects that have already being generated by the creation of the
Artillery Avenue. One impact will be the decrease in humidity due to wind and more sunlight penetration. The forest of Mt. Imbiah is one of two Nature Areas in the Singapore Green Plan.
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(SDC has recently conducted a survey of this coastal forest and the botanical information presented here are obtained from this survey.)
The coastal forest in-itself within the designated Sentosa Integrated Resort site is interesting and worth preserving as an intact block of forest for several reasons:
1) It is a remnant of the original coastal forest on Sentosa, and may be the best surviving example of its kind. With the exception of a very small and highly disturbed patch at Labrador Park, there is no equivalent forest that we know of anywhere else on Singapore. Similar forests in places such as Mt Faber or Kent
Ridge presumably were cleared long ago and now exist as disturbed secondary forests. The forest at the Sentosa IR site is arguably the most important example of the forest type remaining in Singapore due to its diversity, the stature of its trees, the structural complexity of the forest, and its apparent good health.
2) There are a number of enormous specimens of several locally threatened species, in particular Dracaena maingayi. There are a few individuals of this species scattered in primary forest fragments around the main island, such as at
Bukit Timah or in the Central Catchment Nature Reserve, and a number on the slopes of Labrador Park, but nowhere else does this species attain such majestic proportions nor are they found in such numbers.
There are a number of other uncommon tree species, such as:
Bhesa robusta (one very large individual)
Palaquium obovatum ("Nyatoh puteh"; many large individuals)
Elaeocarpus sp. (common in this forest patch)
Garcinia hombroniana (seashore mangosteen; a few specimens of this locally endangered species)
Licania sp. (another uncommon species)
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Alstonia angustiloba, although not rare, is represented by a number of incredibly large individuals, including one of 6m girth. Some of these trees are large enough and old enough to have a number of cavities in them that are suitable as nesting sites for various bird species.
3) The forest grows in a site that is well sheltered. This may explain why the forest, despite its small size, is able to harbour a great number and variety of large trees. Moreover, the many saplings and seedlings present, particularly where the forest is thickest, suggests that the forest is not in decline, but is able to maintain itself. The forest will thus require minimal maintenance in the future if kept as a unit.
4) Should the young trees be cleared, the ability of the forest to sustain itself might be greatly reduced, as there would not be a ready supply of saplings ready to replace the mature trees. Furthermore, without the smaller trees and saplings, the patch would be reduced to a parkland or arboretum rather than a forest ecosystem. There is no telling when any one of the large trees could succumb to a sudden storm or lightning strike, and despite the best efforts to save the big trees, the work would have been in vain if the ability of the forest patch to sustain itself were severely limited by a lack of small and medium-sized treelets and saplings to take replace the large ones.
5) The understorey species Anisophyllea disticha ("mousedeer plant" or
"leechwood") and Canthium confertum are found at the thickest and richest section of the forest. These are species that thrive best with a good canopy overhead and a relatively high level of humidity - conditions lacking in disturbed secondary forests. The persistence of these plants, often associated with primary forests, suggests that the forest is alot closer to the original vegetation on the iste than many people think. It also suggests that the microclimate at the site is
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conducive enough to support an array of primary forest species. In other words, not only is the patch of forest at the Sentosa IR site already interesting as-is, it has the potential to be restored to become an even more diverse and complex forest.
6) The forest is not completely pristine throughout, and its long-term sustainability could probably be enhanced by undertaking a number of management measures: these include reducing the number of nibong (Oncosperma tigillaria) clumps, as these appear to be suppressing the growth of seedlings of other species. Where the forest tapers off to a thinner strip, it might be helpful to augment humidity levels by installing a basic sprinkler or misting system. With minor maintenance, the entire forest could become an even richer, diverse, and ecologically important part of Sentosa's green heritage. Dracaena reproduction and establishment would be worth studying in order to better understand its natural history and its ability to regenerate onsite.
A rapid survey involving two morning sessions was carried of the birdlife of the coastal forest in 2007. This list of the results of this survey is in the Appendix and it is not to be taken as an exhaustive or definitive list so far. More species will most probably be recorded with more surveys --- especially during the migratory period which is now almost over..
32 species of birds are recorded --- with 30 residents (RB & R (B)) and 2 migrants (WV & PM). This constitutes about 9 % of the total (350 species) recorded in Singapore (Nature Society Pocket Checklist 1999).
Two of the resident species are Rare and these are: the Buffy Fish Owl, which is
Nationally Threatened and the Blue-winged Leafbird, which is Nationally Nearthreatened. The forest here provides a congenial roosting site for the Buffy Fish
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Owl and the species (either in a pair or a singleton) can be found only in a handful of other locations in Singapore.
There are also 3 Uncommon resident species and these are: the Stork –billed
Kingfisher, the Hill Myna and the Rufous-tailed Tailorbird. The Stork-billed is found at the edge of the forest on the coastal side.
There is also the Tanimbar Cockatoo, an introduced species here, which is
Globally Near-threatened.
What is interesting is that there are 10 species that are typical of secondary tropical rainforest in Singapore such as the Hill Myna, the Buffy Fish Owl, the
Blue-winged Leafbird, the Dark-necked Tailorbird, etc. Their presence shows that the site is a bona fide tropical rainforest eco-system although not pristine. As such this stretch should be protected as it is and as integral to the Mt. Imbiah cluster cluster --- because tropical rainforest whether secondary or primary constitutes now only a very small percentage of the landcover in Singapore
(constituting about ony 3 % of the total land area.) The thinning or cleaning up of the forest here will affect drastically these species especially the rare and endangered Buffy Fish Owl.
SDC has taken great care of the various forests on the island. Sentosa’s commitment to the preservation of the existing forest can be seen in the efforts and money invested to make this coastal stretch an attractive and meaningful eco-educational experience for visitors. Pleasant nature trails, informative signboards, rain-shelters, etc., have been set up and this is very laudable.
We certainly share SDC’s view, as displayed on the signboards at the site, that
“being just one degree north of the equator --- the wet tropics --- Sentosa is primarily an equatorial lowland rain-forest. The trees here grow very fast, forming
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the tallest canopy forests up to 50 metres (150ft) high. These trees may live for hundreds of years”. Yes, “the natural ecology of Sentosa is the equatorial rain forest ---- a veritable paradise of fauna and fauna”. Although not primary or original, we also share SDC’s commitment and effort to ensure that the “island forest is now being carefully nurtured to sustain the fragile ecological balance” so that it will eventually grow to maturity and return hopefully to it original state.
However, when SDC awarded the northern coastal forest for the development of
Sentosa Integrated Resort, we are concerned that this laudable commitment and effort will be jeopardized. We here strongly urged that such a commitment to the protection of the remaining tropical rainforest at Sentosa be sustained by both
Resorts World and SDC.
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Submitted by hand at the Sentosa Coastal Forest Forum on 17 March 2007 to:
Sentosa Development Corporation, Resorts World, & Assoc. Prof. Simon Tay
(Chairman of the Forum). Also to National Parks.
Acknowledgment: The Conservation Committee would like to thank the following for their contributions & feedbacks to the formulation of this report: Angie Ng, Ho
Goh Si Gium, Hua Chew, Shawn Lum, Tan Beng Chiak, Alan Owyong, Willie Foo
& Alfred Chia.
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Nature Society’s Address:
510 Geylang Road # 02-05, The Sunflower, Singapore 389466; Tel: 67412036;
Fax: 67410871.
Contact:: Dr Ho Hua Chew, Chairman, Conservation Committee: Tel: 64571196;
E-mail: hohc@starhub.net.sg
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