Stars of Singapore

Sea stars are encountered on almost every shore in Singapore. Even the most "beat up" shore will have some kind of sea star. Unlikely starry shores include this one in the photo above, of Cyrene Reef which lies in the middle of Pulau Bukom, Jurong Island and faces our container terminals! While Chek Jawa appears to have the richest variety of sea stars, there are also sea stars that are only found on our Southern reefs.

Here's a quick look at some of Singapore's Stars!

Although often called starfish, these creatures are not fish at all! So we prefer to call them sea stars. Sea stars belong to a group of animals called Echinoderms (Phylum Echinodermata).

Here are some sea stars that can be found on our sandy shores.
The sand stars (Astropecten spp.) have large spines on the sides of their narrow arms and can move about speedily across the sand on their pointed tube feet. They also burrow rapidly into the sand. They come in a variety of patterns.

The Common sea star (Archaster typicus) is alas, no longer common. Those on Chek Jawa were wiped out in early 2007 following the massive floods in Johor. But there are signs of them returning. They are still commonly seen on Southern islands such as Pulau Semakau, Pulau Hantu and Kusu Island. Often you might seen one Common sea star on top of another, with arms locked. This is a unique mating position of this kind of sea star. Their reproductive parts don't actually meet. They are just getting close to one another getting ready to release eggs and sperm at the same time.

On the rocky shores and seagrass meadows, more sea stars!The small Crown sea star (Asterina coronata) is usually brown and drab and found under stones on our Northern shores. But sometimes, bright orange ones can be seen! Gymnanthenea laevis is a rarely seen star, sometimes with orange spots at the tips of its arms. It is most often seen among seagrasses. Big ones can pinch your fingers if you hold it, as they have large pinching structures.

The Biscuit sea star (Goniodiscaster scaber) really looks like it was made with a cookie cutter! This neat star is often seen among seagrasses as well as on coral rubble areas in the North.

These sea stars are rarely seen and may be seasonal: the large eight-armed Luidia maculata and the small, rather boring looking Nepanthia sp. They are sometimes seen on undisturbed shores in the North.

Sea stars of the coral rubble and reefs include some of the largest of our stars, some of which can be bigger than your face!
The Cake sea star (Anthenea aspera) with short fat arms is sometimes seen and comes in a wide variety of colours and patterns. The big red Knobbly sea star (Protoreaster nodosus) is the highlight of any trip to the reef. Besides red ones, you might also see brown or even white ones. They are seen both at Chek Jawa and Pulau Semakau, in coral rubble areas.

The Cushion star (Culcita novaeguinea) doesn't look like a star at first glance, but a look at the underside shows its sea star feature of five grooves. This cuddly star is seen in deeper waters in reefs, more often by divers than visitors to the intertidal.

The business side of the sea star is underneath!
The mouth is in the centre of the arms, and there are grooves on the underside of each arm. These grooves contain rows of tube feet. Sea stars use their tube feet to move around. Sea stars also use their tube feet to manipulate food. Some sea stars also breathe through their tube feet!

Sea stars use seawater instead of blood to pump up their bodies and move their tube feet. Thus it is stressful for sea stars to be left out of water for too long. Please return sea stars quickly to where you found them.

What do sea stars eat? Some sea stars placidly gather edible bits from the water or surface. But most sea stars are scavengers or carnivores, 'sniffing' out their meal by the chemicals released by the prey or dead animals. Among the more common prey are snails, bivalves, crustaceans, worms and other echinoderms. Some sea stars specialise in a certain prey. Some sea stars feed on sponges, sea anemones and corals. A population explosion of the notorious Crown-of-Thorns sea star (Acanthaster planci) can decimate reefs. Fortunately, this sea star has not been encountered on our shores.

More FAQs about sea stars

I went to the seashore and didn't see any sea stars! Sea stars tend to be more active after dark. In fact, we notice that as night falls, the stars literally come out! In the sand as well as in the sky. Some stars are very secretive, hiding under stones or in crevices among coral rubble. Even big stars like the Cake sea star can be stuffed deep under coral rubble.

I heard sea stars can regenerate from broken limbs. Can I try and see what happens if I chop one up?
Most sea stars can regenerate portions of limbs that got nibbled off by a predator. But this regeneration takes a long time. You can't see it happening in front of your eyes. And meanwhile, the sea star is handicapped by a lost limb. Very few can reproduce from broken limbs, and none of our sea stars do that. If our sea star is severely injured, it will die. So please don't mutilate the sea stars. It is cruel to do so.

Should I take home the dead sea star I found on the shore?
All the sea stars that you see on our shores are probably alive. You are unlikely to come across a skeleton of a sea star. Dead sea stars disintegrate quickly and do not leave behind whole skeletons. A live sea star also has moving tube feet. When removed from the water, however, sea stars will retract their tube feet and may appear dead.

Should I take a sea star from the shore and put it in my home aquarium? Aquarists and scientists don't really know what the various sea stars eat. So your sea star might die of starvation. Or it might start to eat its tank-mates. For this reason, sea stars are not popular for the home aquarium.

Threats to sea stars: Sea stars are not eaten by people. They are also not that popular for the live aquarium trade as they tend to eat their tank-mates. However, in some places, sea stars are harvested alive and dried to be sold as cheap ornaments. This is a cruel waste! Don't support this harmful trade. Don't buy souvenirs or trinkets made from marinelife.

Our sea stars are no longer as common as they used to be. Common sea stars once littered the Changi shores, but they have not returned since the reclamation. The big red Knobbly sea star used to be considered one of the most common sea stars in the Malay peninsula. Now both the Common sea star and the Knobbly sea star are listed among the threatened animals of Singapore, due to habitat loss.

Stay tuned for more sea star cousins
More about brittle stars, feather stars, sea urchins, sea cucumbers and other echinoderms of Singapore.

Links to more about sea stars
Lane, David J.W. and Didier Vandenspiegel. 2003. A Guide to Sea Stars and Other Echinoderms of Singapore. Singapore Science Centre. 187pp.
Photos of sea stars of Singapore on wildsingapore flickr
Sea stars and echinoderms at Changi recent sightings on the tidechaser blog

Chek Jawa: jewel of the northern shores

Throughout 2008, this blog will feature articles on Singapore's reefs and shores, marinelife and the people who work for them.

For January, we thought it most appropriate to feature Chek Jawa, a shore that attained fame when it was spared from reclamation.Chek Jawa does have reefs, although these are small and fragile and not on the route of public guided walks. Chek Jawa, however, boasts a range of shore ecosystems that are now rare on Singapore.

Here's more about Chek Jawa!

Coastal Hill Forest
The hill overlooking Chek Jawa is cloaked in rare trees and plants. These shelter and feed a variety of animals. Many of these plants and animals are no longer commonly seen on mainland Singapore.
Some of the rare birds that live in the coastal forest include the wild Red junglefowl. Here's more details of a recent encounter with junglefowl on Chek Jawa shores on the bird ecology study blog.
Among the rare trees you may see in the coastal forest are the Seashore nutmeg with its red fruit and the Delek air with its stunning blue flowers.

Mangroves
The mangroves of Chek Jawa are now easily explored by the new boardwalk.
Unlike the coastal forest trees, mangrove trees are adapted to being covered in seawater at high tide and to grow in soft mud. They have odd roots and other adaptations as a result of this.
Mudskippers are the highlight of a visit to these mangroves! Other delights include fiddler crabs and mangrove crabs. The kingfishers also hunt along the mudflats near the mangroves. At high tide, from the boardwalk you might spot all kinds of fishes.

Rocky shores
Chek Jawa is among the few places left in Singapore with a natural rocky shore, gravel beach and other interesting rock formations.
At low tide, we can have a closer look at some of the strange animals that live here, including barnacles, crabs and fierce shell-drilling snails. Under the rocks are even more amazing animals such as living cowries, sea stars and fast flat crabs.

Sandy shore
The sand bar is the backbone of Chek Jawa and provides a home for all manner of intriguing creatures.
The Common sea star is a must-see with visitors. Sadly, it is no longer common elsewhere in Singapore. And even more sadly, those on Chek Jawa were wiped out in early 2007 following the massive flooding in Johor. More about this in an upcoming feature article on this blog.

The sand dollar is another intriguing creature to examine, as well as sand crabs and strange worms that build tubes in the sand.

The sand bar is also a popular rest stop for shorebirds that fly in from as far away as Siberia. Overhead, majestic birds of prey hunt for fishes in the sea.

Seagrass Meadows
A calm, shallow lagoon lush with seagrasses forms behind the sand bar. Seagrasses are now rare in Singapore due to habitat loss. Chek Jawa is one of the few places where ordinary people can still see them and the many strange animals that live in this special ecosystem.
First-time visitors are often stunned by the carpet anemones which are bigger than your face and come in a stunning variety of colours. At some times of the year, the seagrass may be dotted with colourful sea cucumbers. Other seagrass dwellers include secretive crabs and snails. A lucky visitor may also encounter sea hares, squids and mantis shrimp.

Coral rubble and reef
This is probably the richest part of Chek Jawa and also the most fragile.
Rarely exposed, even at low tide, this area shelters delicate sea creatures that prefer to be submerged most of the time. These include sponges in bewildering shapes and colours, delicate fan worms and living corals! Octopuses, seahorses, nudibranchs and colourful flatworms are some of the other amazing residents of this special part of Chek Jawa.

More than reefs
Reefs are part of a spectrum of marine ecosystems. Although reefs are often the most attractive and well known to divers, other marine ecosystems are equally important biologically, and just as fascinating to explore. Ordinary people can visit these intertidal habitats at low tide without having to swim or dive. And it's great fun especially for the kids and young at heart.

More than worms!
Chek Jawa is home to large animals too, although they are rarely seen by visitors.
A fascinating sign spotted in 2007 were dugong feeding trails! More about this on the teamseagrass blog and another sighting of dugong also on the ubin volunteers blog. Other amazing creatures recently sighted at Chek Jawa include two otters on the tidechaser blog, and a civet cat on the wildfilms blog.

Stay tuned for more about Chek Jawa
Upcoming feature articles will share more about Chek Jawa's recent history, more about the (sea) stars of Chek Jawa, and other fascinating aspects of this amazing shore. So do check back regularly or subscribe to the rss feed on this blog!

Links to more information
More about Chek Jawa's ecosystems on the wildsingapore website
Information for visitors to Chek Jawa how to get there, what to do, on the wildsingapore website
Guided intertidal walks on Chek Jawa by the Ubin NParks volunteers
Guided Chek Jawa boardwalk tours by the Naked Hermit Crabs
Blogs about Chek Jawa visitors, volunteers and more from the wildsingapore google reader
Photos of Chek Jawa on wildsingapore flickr

Reefs in Brief: Labrador Nature Reserve, Sentosa reclamation

Port expansion plans will take place next to Labrador Nature Reserve soon. The media reports "Singapore port project: $20m to limit harm to environment" while blogs show views of the situation on the ground.

Meanwhile reclamation at Sentosa for the Integrated Resort continues apace. Plans to use captive dolphins for spa therapy at the Sentosa IR are announced, at the same time that a report suggests that dolphin therapy is a dangerous fad.

Other Singapore shore news: Chek Jawa intertidal tours will no longer be free as of Jan 08.

Elsewhere some good news: A study finds that whale sharks visiting Ningaloo are thriving, another study shows that conserving green turtle nesting sites helps these turtles recover, commercial fish collectors agree to stop harvesting clownfishes at Keppel Island, Great Barrier Reef.

And a thought-provoking article "Blue in green: It's time to put greens in their place" about the need to highlight blue conservation work.

Reefs in Brief: dugongs die in gill nets and more

Dugongs were recently found drowned in gill nets in Abu Dhabi. Abandoned gill nets are a problem on Singapore shores too, and threaten our dugongs as well.

High tides are expected to exacerbate flooding over Christmas weekend in the region.

High tides are expected in Malaysia and Indonesia and Singapore too. Meanwhile, there were reports that sea level rise could be twice as high as earlier thought.

And in It's time to put greens in their place on the Economist, there is a discussion of the serious consequences of "terrestrialism" and the need to focus on the seas.

Reef in Brief: Dolphins sighted in Singapore! and more



Dolphins sighted: videos, photos! New Coastal and Marine Environment Programme in Singapore. But floods in Johor are of concern. The Coral Triangle is raised at Bali; and there's been another massive oil spill, in the North Sea.

Siyang spots DOLPHINS again! At St. John's Island on his urban forest blog. And shortly after, Chee Kong spots dolphins too, also at St. John's see his YouTube clip.

NParks is looking to fill positions for the Coastal and Marine Environment Programme, an inter-agency initiative to strengthen Singapore's capacity in areas related to the coastal and marine environment! Looking forward to learning more about this initiative.

There have been floods in Johor since about a week ago with thousands evacuated. What do floods have to do with our marinelife? Earlier this year, massive flooding in Johor was followed by mass deaths on Chek Jawa. Kok Sheng is carrying out a project to monitor the recovery at Chek Jawa following this incident. Let's hope the current floods will not have a similar aftermath.

The Bali Climate Talks provided an opportunity to highlight the need to conserve the Coral Triangle. The Coral Triangle spans 5.7 million square kilometres from the northern tip of the Philippines to the Indian Ocean below Singapore and as far west as the Solomon Islands. While it covers just two per cent of the world's ocean, it contains 76 per cent of all known coral species and 53 per cent of the world's coral reefs.

Just after the oil spill in South Korea there's been another massive oil spill in the North Sea. About 25,000 barrels of oil were spilled. By comparison, the Exxon Valdez tanker spilled about 240,000 barrels of crude.