Discovery @ Semakau on 21 March 2008

Fifty Second Discovery Posting:

It was Good Friday (21 March 2008) and a batch of us were out on Semakau with Dr Dan and his group of students. Although this was a trip especially for Dr Dan's students who were from Duke University to explore our shores, i didn't really play a good host to them as i had other ideas on mind for going to Semakau =P.

Well, I was hoping to locate juvenile knobbly sea stars (Protoreaster nodosus), wanted to do it because CK couldn't find any of them during the last exploration trip and my mini study on them was still on.

As i was walking away and probably much ahead of others, i didn't manage to spot as much things as them, probably because i only have one pair of eyes. =P

But after about 20 minutes and not much luck in spotting anything, I saw my 'goal' of the trip. YES! First 'discovery' (picture below)!
Discovery Note:
1. This knobbly sea star was probably about 10cm in length for each limb. About one time bigger than the juvenile knobbly we saw last time when we were on Semakau.

Maybe my luck wasn't that bad after all, i thought, so with my hopes higher, i moved on.

And shortly after, i came across the second 'discovery', a synaptid sea cucumber (picture below).
A closer look near its mouth (picture below).
Discovery Note:
1. It has no tube feet except for highly modified ones that form the oral tentacles.
2. It has a very thin, delicate body wall that feels sticky to touch. The stickiness is not due to mucus or other adhesive, but to other hundreds of tiny, anchor-shaped ossicles located in the skin.

We were really lucky to have a almost clear sky on the day. Because if it's clear, we will get to see the sunset! Here's the first of the set of sunset photos i took on the day (picture below). As i continued to look around amongst an area of seagrass, i saw a stir of the sand nearby and a closer look proved to be the third 'discovery', a coastal horseshoe crab (picture below)Discovery Note:
1. Horseshoe crabs have known to 'roam' the earth since days even before the dinosaurs was around, so scientists calls them 'living fossils'.
2. Although they are called horseshoe crabs, they are not related to crabs. They are actually more related to spiders and scorpions.
3. There are two types of horseshoes crabs which we can find in Singapore, the mangrove one (circular tail) and the coastal one (the trianglar tail)
4. The tail is not venomous and is not used as a weapon. It is merely used as a lever to right itself if it is overturned. If you see an upside down horseshoe crab struggling with its tail waving around, do give it a helping hand. It will not hurt you.
5. The blood of the horseshoe crab is blue, as it is copper-based.
6. Their blood is able to clot easily when it detects bacteria, so their blood was harvested for these purposes until a team from NUS's department of Zoology has cloned a substance to replace using horseshoe crab's blood. Read more about it here.

And just not far away from what i saw the horseshoe crab was some round shapes on the sand. Oh, sand dollars. (picture below ) And this is fourth 'discovery'.Discovery Note:
1. Living sand dollars are coated in fine, harmless spines that made them very velvety.
2. The spines are movable and are used to dig into the sand or move around.
3. The dense layer of spines also helps to keep off sand and silt so there is a flow of oxygenated water across the body.

As the sun continued its descent down to the horizon, i continued my photo taking of its movement (picture below). And as i went on walking around the seagrass area, i spot this mosaic crab (picture below), fifth 'discovery'.Discovery Note:
1. This is one of the most poisonous crab in Singapore.
2. Thus, I give the strongest advice not to eat this. =)

The beautiful sunset again (picture below). As I rejoined the main group, CH cried out, 'Knobbly'. And i not wanting to miss another chance to see another knobbly went over and it was another knobbly sea star (picture below) which was similar in size to the one i saw earlier. What luck!Finally, a photo of the full moon from the shores we were at (picture below). PY commented at the sides that this didn't looked like we were on Singapore and i agreed totally. =)Lastly (really the last), it's thanks again everyone!

Extra:
a) More about the trip on Wildfilms.
b) Check out the seahorse they saw on Colourful Clouds.
c) A very very tiny cowry on manta's blog.

Semakau Inter-Tidal Walk on 9 March 2008

Fifty First Discovery Posting

Singapore. An island with one of the most busy ports in the world (picture below).
It is also our fortune to be able to view reefs within an hour of boat ride from our city at our southern islands. Yes, we have coral reefs in Singapore! Read more about them here.

Yesterday, we were on Pulau Semakau ,one of these special southern islands, where we can view coral reefs without having to dive (picture below). Do you know that this island is also first offshore landfill island and last landfill in Singapore? Read more about it here.
My job again was a hunter seeker, together with CH, Robert and HW. Basically, we are in charged of finding the interesting flora and fauna for our visitors. Here's us moving past the forest trail(picture below). Upon exiting the forest trail, Robert spotted a net off the side. And a closer look brought a shock for us, as there were two trapped horseshoe crabs which were alive! Immediately, we sprung into action and released the first 'discoveries' from the net (picture below). Discovery Note:
1. Horseshoe crabs have known to 'roam' the earth since days even before the dinosaurs was around, so scientists calls them 'living fossils'.
2. Although they are called horseshoe crabs, they are not related to crabs but more related to spiders and scorpions.
3. There are two types of horseshoes crabs which we can find in Singapore, the mangrove one (circular tail) and the coastal one (the triangular tail)
4. The tail is not venomous and is not used as a weapon. It is merely used as a lever to right itself if it is overturned. If you see an upside down horseshoe crab struggling with its tail waving around, do give it a helping hand. It will not hurt you.

After the rescue 'mission', we proceed to start our seeking. And very soon, we managed to find the resident gigantic carpet anemone (picture below), second 'discovery'.
Discovery Note:
1. For self defence and preying purposes, they have stinging cells in their tentacles which will release or 'shoot' small 'needles' when upon contact. So I won't really advise you to touch them although our skin might be 'thicker' than most marine creatures. This is to prevent you from getting stung.
2. They lack an anus, so they split out any indigestible food through its mouth.

Third 'discovery' is a flatworm (picture below). Discovery Note:
1. Flatworms are hermaphrodite, which means a flatworm has both the male and female sex organs.
2. And certain species of flatworms engage in penis fencing, in which two individuals fight, trying to pierce the skin of the other with their penises; the first to succeed inseminates the other, which must then carry and nourish the eggs.

Fourth 'discovery' is something that looks a little like a flatworm. But it's not, this is a kind of sea slug, a Chromodoris nudibranch (picture below)Discovery Note:
1. 'Nudibranch' means 'naked gills'. The name comes from the flower-like gills found on the back of many nudibranchs. These nudibranchs use the gills to breathe.
2. Nudibranchs are related to snails. Little baby nudibranchs are born with shells, but they lose them when they become adults.
3. Most nudibranchs are carnivores, they eat immobile or small, slow-moving prey. Examples are sponges, ascidians, hard corals, soft corals, sea anemones etc.

Fifth and sixth 'discoveries' are sea cucumbers, the one above is the ocellated sea cucumber while the one below is the sandfish sea cucumber (picture below).
Discovery Note:
1. The popular Chinese name for sea cucumber is haishen, which means, roughly, ginseng of the sea.
2. Being related to the sea stars, sea cucumbers have a soft, wormlike body and range from a few centimeters to 90 centimeters in length.
3. Unlike the sea star, however, they have no arms but use a cluster of tube-like feet around their mouth to gather food.
4. To repel predators or when stressed, a sea cucumber might expel their innards or ‘vomit’. And if too much of their innards are expelled, they might die off as a result.
5. The sandfish sea cucumber is the species of sea cucumber which people consume. But they contain toxins, so it must be properly prepared before consumption.

Now after finding a number of interesting things, it was time to look for the icon of the walk, the knobbly sea star. After some hard work from us, here is seventh 'discovery' (picture below).
Discovery Note:
1. They get their name from the knobs they have.
2. Although most of them are mostly red or orange in colour, beige or brown coloured knobbly sea stars have been spotted before also.
3. Can you believe that a knobbly seastar might be larger than your face? It’s about 30cm across! (look at the pictures below to get an idea)

After managing to find the icon, i decided to take a breather and take photos of the groups coming over to have their group photo taken with our icon. Here's ST and HK's group in the progress of taking the photo (picture below) PY's group posing with the knobbly sea star (picture below)And of cos the beautiful sunset... (picture below)Finally, thanks to everyone for making this trip another wonderful and joyful one!

Extra:
a) Dr. Yaacob Ibrahim, Minister for Environment and Water Resources, also participated with us for this trip. Read more about it at Nature Scouter's blog.
b) Also check out what did Nature Scouter aka SJ saw during the trip.
c) Read Tidechaser's experience of guiding Dr. Yaacob.
d) And of course Manta's experience.

Semakau Inter-Tidal Walk on 8 March 2008

Discovery Posting Number Fifty!

For the second public walk of the year 2008, i was assigned to be one of the hunter seekers, which means i have to find interesting things and mark them out for the guides, which also equates to if i can't find anything, i will be very stressed... Anyway, today, CH was together with me on this 'job'.

Although this 'job' is stressful in a way, it does have its benefits, we get to have a bit of time (it's really not much) to take photos, here's a photo of part of the inter-tidal area of Semakau (picture below)
And be the first to cross the seagrass lagoon and enjoy the view of the clear waters (picture below).
And of course the feeling of finding something interesting is really great! Here's 'first' discovery', an upside down jellyfish (picture below)
Discovery Note:
1. Its name is thus because you will usually find this jellyfish upside down.
2. The upside down position allows zooxanthellae which lives on the underside of the jellyfish to get sunlight so they can photosynthesize.
3. And the zooxanthellae when photosynthesizing shares its food with the jellyfish, while the jellyfish gives the zooxanthellae a place to call home.
4. So they have a symbiotic relationship.

Second 'discovery' should be a juvenile noble volute found by CH(picture below).
Discovery Note:
1. Volutes are carnivorous.
2. They prey on bivalves, enveloping the victim completely with their foot forcing the bivalve to finally open from exhaustion and lack of oxygen.
3. They can grow to more than 20cm and used to be common but now threaten due to 'harvesting' from humans and habitat lost. So it's really great to see a 'young' one!

Third 'discovery' should be a great egret (picture below) which was perching at the reef edge area (picture below).
Discovery Note (information from Sungei Buloh online guidesheet):
1. Great Egrets feed on mostly fish, but will also take amphibians (frogs), aquatic invertebrates (insects, crayfish), and reptiles (snakes).
2. Great Egrets are skilled hunters.
3. They stalk the shallow waters or mud flats, walking slowly or quickly with their strong neck coiled at ready. And when suitable prey is spotted they straighten out the neck, to instantly snatch the prey. When fishing, they may tilt their heads to one side, possibly to avoid the glare of the sun's reflection on the water.
4. Great Egrets may also use their feet to stir up the water and scare up a victim.
5. For more information on the great egret, click here.

As I walked around to find more interesting marine creatures, CH spot a blue-spotted stingray trapped in a net, and with the help of Shawn (NEA staff), it was freed. Fourth 'discovery'.
Discovery Note:
1. The position of the eyes allows the blue spot stingray to see almost behind it.
2. The gills and mouth are found on the underside of the body.
3. The blue spot stingray doesn't really have teeth—instead, the mouth is outfitted with two food-crushing plates.
4. Rays dart away when they sense trouble approaching. When caught off guard, these fish fend off predators with a flick of the tail, which is equipped with two venomous spines. Since its tail is so long, the blue spot stingray can even strike at animals directly in front of it.
5. The large tail spine of the blue spot stingray is dangerous and even deadly. The barbs in the tail are so large; people have bled to death from a sting.

In the end, we managed to find quite a number of marine flora and fauna for the visitors. However, in the view that many others might blog about this trip, I'll leave the job to them. Or you could say I'm a bit lazy. =P

Extra:
a) See more creatures on Tidechaser's blog entry.
b) Read more about the anemone shrimp on Urban Forest.

Anyway, thanks to all again for this wonderful trip to a favourite place. =)

Semakau Inter-Tidal Walk on 23 Feb 2008

Forty Ninth Discovery Posting:

A familiar sight at a familiar place (picture below).
This is Semakau (picture above). Singapore's first offshore land fill and now the last land fill. And on the shores of this island is where RMBR with its volunteers conduct guided Inter-Tidal walks.

Just yesterday, I was out on Semakau for the first guided Inter-Tidal walk for visitors. For this walk, i was leading a group of students from the ITE Green Club and two of their teachers and my group was called the puffer fish, one of the five new group names we have for 2008.

So here's some of the things we saw, first 'discovery', a hairy crab! As i said, not the same crabs we get from Sri Lanka =P (picture below)
Discovery Note:
1. The hairs of the hairy crab traps sediment so it blends 'almost' perfectly with its surroundings.
2. We also call this crab the ‘teddy bear crab’. =)
3. The hairy crab eats seaweeds and poisonous zoanthids, which makes the crab mildly poisonous too!

Second 'discovery' is this very beautiful heart cockle which one of our hunter seekers, ST, found (picture below).
Discovery Note:
1. The cockle lives in sand and mud in shallow water.
2. All cockles are hermaphroditic, which means they possess both the male and female sex organs.
3. Show your love by not taking them away from their homes as they are a rare find on our shores. =)

And amongst one of the pool around the zone, we saw this fan worm (picture below), third 'discovery'!
Discovery Note:
1. They get their common name from the appearance and structure of their modified tentacles on their head.
2. These modified tentacles are used for feeding. By the way, they do filter feeding.
3. They retract almost instantly into their tubes at the sense of any movement, shadow or danger near them.

And as we walked further nearer to the reef edge, there were these mushroom corals (picture below) which our sharp-eyed hunter seekers spotted. Fourth 'discovery'.
Discovery Note:
1. Most mushroom corals do not form colonies like most other corals and most mushroom coral is usually a single polyp.
2. Unlike most corals, most mushroom corals are attached to the reef only when they are small.
3. As larger individuals, they will detach themselves from the reef (if they had attached themselves to the reef) and live loose on the seafloor.

Our hunter seekers for this trip were really had "two brushes" (which means really good). They managed to find this hardly seen nudibranch, fifth 'discovery', which i only seen one on Feb 2007 on Semakau (picture below). It was too bad i didn't had the time to take a better photo but hopefully i will see it soon again. =) Discovery Note:
1. Nudibranchs are essentially snails without shells, and their name literally means "naked gills".
2. In most species, the gills are prominently displayed on their dorsal (upper) surface.
3. They have a pair of tentacles (called rhinophores) located on top of their heads, which biologists believe are used as sensory organs to assist in finding food and seeking a mate.
4. This nudibranch (picture above) might be the Ceratosoma sinuata.

Lastly but not the least, the star of the walk and i mean it. The knobby sea star! Sixth 'discovery'! Here's a traditional group shot of the star with my really cool group (picture below).
Discovery Note:
1. They get their name from the knobs they have.
2. Although most of them are mostly red or orange in colour, beige or brown coloured knobbly sea stars have been spotted before also.
3. Can you believe that a knobbly seastar might be larger than your face? It’s about 30cm across! (look at the picture above to get an idea).

Finally, would like to thank all the puffer fishes for being such a great audience and the positive comments. I hope you enjoyed this trip like i did! =)

Discovery @ Tuas Grasslands on 17 Feb 2008

Forty Eighth Discovery Posting:

Let me quote what SY has written, "An initial plan to go Sungei Buloh was changed to the Tuas marshlands; the enticement was to hard for me to resist, even though I was busy doing some assigments." It was an exact situation for me, as i had to complete an uncompleted assignment due on Monday. However, to go to some nature place in Singapore which i have not been to before was too big an attraction for me.

Thus Tuas Grasslands was the place i was at this morning (17 Feb) with LK, HW, RY, ST and SY. With us also were Mr Tang (Dragonfly expert) and several students who were there to study dragonflies.

Did i mention this place was a great place to observe dragonflies?

And as we were walking along the path just next to the grassland, this butterfly (picture below) attracted our attention and immediately our cameras were out! First 'discovery' and this might be the Tawny Coster, Acraea violae.
Discovery Note:
1. According to what i read, this species migrated from Thailand to West Malaysia and then to Singapore! Read about this at here.

And we actually saw the caterpillars of this butterfly back on Ubin in Jan, here's a photo of them i took back then (picture below).
Would this look like a place in Singapore to you (picture below)? I am wondering how many natural grasslands do we have right now...
Another look at this place with LK leading the way for the students (picture below).
Along the way, LK pointed out this rare orchid that grows from the ground (picture below), by the way, most orchids are epiphytes. This is the Spathoglottis plicata or Lumbah Tikus, second 'discovery'.
Discovery Note:
1. This is a orchid that can be found in forests or reclaimed land (Tuas Grasslands is reclaimed land)
2. The colours of the sepals and petals are variable, ranging from white to dark purple.

If you are wondering what is an epiphyte...

Discovery Note:
1. Some sources say an epiphyte is a plant that grows on another plant but does not receive its nourishment from that plant.
2. Other sources say that an epiphyte is an air plant, which is described as a plant that does not grow in soil.
3. Both definitions accurately describe an epiphyte.

After walking further into the grasslands, we reached this marshland like habitat (picture below) where the students were busy at work while we continued to explore around.
And as i walked around, i spotted the third 'discovery' which looks like a pond wolf spider, Pardosa pseudoannulata (picture below). Discovery Note:
1. This spider is easily recognised by the two dark bands on the carapace and ring-like markings on the legs.
2. Most Wolf Spiders hunt on the ground.
3. Female Wolf Spiders are recognised by the spherical egg-sac that is attached to their spinnerets. Read more about them at here.

And just right next to where we were was the sight of development (picture below), it is said that this place will be developed into a racing course for riders. But is there a need to destroy everything? =( Extra (read more about the things we saw to understand why we are sad that this place is going to be gone soon):
a) Check out Tidechaser's entry to see the many dragonflies we saw.
b) Read Urban forest to know why this place is such a great place to see dragonflies.
c) Discover more about the carnivorous plants we saw at this place from Manta's blog.

Finally, it's thanks to LK for planning this trip and all others for making this another enjoyable trip.

Interested to find out how many kinds of dragonflies we can see in Singapore?
> Visit Mr Tang's website on dragonflies here.

Discovery @ Semakau on 8 Feb 2008

Forty Seventh Discovery Posting

In preparation of the first public Semakau Inter-tidal walk on 23 Feb 2008, a whole batch of current Semakau Guides and new trainees were out at Semakau today (8 Feb 2008).

Here's part of the group just crossing the 'starting point' of the forest trail to reach the Inter-Tidal area on Semakau (picture below).
And while the rest of the gang were out exploring, Ron lead a group of trainees for their practical session and I was kinda of arrowed to do hunter seeking.

Here's first 'discovery', the common sea star, Archaster typicus (picture below).

Discovery Note (Warning: Sex Content):
1. This is a 'mating' position for the sand star.
2. The 'mating' position for the common sea star works like this: the male will be on top of the female, their arms in a formation as in the picture.
3. But they do external fertilization, which means their sexual organs don’t come into contact and the closeness is to increase the chance of fertilization, when they release the eggs and sperms into the water.
4. This 'mating' position is consider unusual in the world of sea stars, as only the common sea star and one other related species is known to “mate” in this way.

I think second 'discovery' looks like some egg capsule (picture below). But still not sure at this point. Can anyone enlighten me?
Yesterday at Hantu, i saw a Spiral melongena laying eggs on Pulau Hantu. This time, it was a volute laying eggs (picture below)! Third 'discovery'.
Discovery Note:
1. Volutes are carnivorous.
2. They prey on bivalves, enveloping the victim completely with their foot forcing the bivalve to finally open from exhaustion and lack of oxygen.
3. They can grow to more than 20cm and used to be common but now threaten due to 'harvesting' from humans and habitat lost.

Here's the trainee group in action and with Ron showing them something (picture below), i can't remember what it is though... haha =P
Anyway, as i continue to walk on to look for interesting things, an octopus moved past my legs. And before it could hide itself under a rock, i quickly took a shot of it (picture below). Fourth 'discovery'.
Discovery Note:
1. Octopuses are characterized by their eight arms (not tentacles), usually bearing suction cups.
2. They have a relative short life span, and some specials live for as little as six months.
3. They have three hearts! Two pump blood through each of their two gills, while the third pumps blood through the body.
4. They are also highly intelligent, probably more intelligent than any other order of invertebrates (any animal without a spinal column).
5. They are also able to change their body colour to camouflage themselves.

Extra:
View a video about these colour-shifting abilities of sea creatures here.
Do watch it as it amazed me. =)

Anyway, as i walked on. I came across the fifth 'discovery', the sandfish sea cucumber (picture below).Discovery Note:
1. The popular Chinese name for sea cucumber is haishen, which means, roughly, ginseng of the sea.
2. Being related to the sea stars, sea cucumbers have a soft, wormlike body and range from a few centimeters to 90 centimeters in length.
3. Unlike the sea star, however, they have no arms but use a cluster of tube-like feet around their mouth to gather food.
4. To repel predators or when stressed, a sea cucumber might expel their innards or ‘vomit’. And if too much of their innards are expelled, they might die off as a result.
5. The sandfish sea cucumber is the species of sea cucumber which people consume. But they contain toxins, so it must be properly prepared before consumption.

Sixth 'discovery' looks like a peacock anemone (picture below).
Discovery Note:
1. They are named peacock anemones because of the many colours and patterns we can find.
2. They are cnidarians like sea anemones and jelly fishes, which means you shouldn't touch them with your hands as they may be stung by the peacock anemone.

As the night came, lots of crabs started to appear, here's one of them, the red egg crab (picture below) and this is the seventh 'discovery'.
Discovery Note:
1. Egg crabs are highly poisonous and contain toxins which are not destroyed by cooking.
2. Since other animals don't particularly want to eat this crab as it is poisonous, it is slow moving and doesn't really bother to hide.

Another crab we saw, eighth 'discovery', is something i don't know its ID (picture below). Can anyone help me? Finally, as we walked back to the shoreline, we found a clown fish aka Nemo just next to a gigantic carpet anemone (picture below)! Ninth 'discovery'!Discovery Note:
1. The clownfish have a symbiotic relationship with sea anemone.
2. They have a mucus covering that protects them from the sting of the sea anemone's tentacles.
3. This mucus prevents them from being harmed, and allows clownfish to live in sea anemone.
4. Clownfish are hermaphrodites (they develop as males first and mature as breeding females or ‘change’ into a female if there are no females).
5. More information? Click here.

Would like to thank CH, JH, HW, Ed, CK who were exploring around, for making my job easier as a hunter seeker by telling me where to look for things they found, Luan Keng for organising this trip and all others!

Oh, would also like to thank Andy for giving a few of us a ride which saved us lots of time in getting home. =)

Extra:
a) Tidechaser's blog entry on other interesting things on Semakau.
b) Manta's blog entry on two nemos at two different locations on Semakau.

Another group of shore lovers were out on Kusu, and check out what they saw on
a) Wildfilms blog
b) NatureScouter's blog.