Sunday, December 14, 2008

Discovery @ St. John Island on 13 Dec 2008

Eighty-Second Discovery Posting:

Together with a group of friends, we explored the little patch of mangroves and the inter-tidal zone of St. John Island.

One great find, the first 'discovery' for this entry is the rarely seen Api-api Jambu (Avicennia marina). Here's a photo of it's fruit (picture below).
Discovery Note:
1. The timber for this tree can be used for firewood.
2. This is the rarest of all Api-api found in Singapore!
3. Read more about it on http://mangrove.nus.edu.sg/guidebooks/text/1050.htm.

Not wanting to miss the low tide for the evening, we immediately moved towards the inter-tidal zone after a short look at the mangroves. And along the sandy beaches, we saw a whole army of soldier crabs! Here's one of them (picture below), second 'discovery'.
Discovery Note:
1. They are quite shy. So if you want a close look at them. You will have to wait silently next to a hole of it and not make any movement if possible.
2. Unlike most crabs which are capable of moving only sideways, the soldier crab can move forwards and backwards as well!
3. Read more about the soldier crab @ http://www.wildsingapore.com/wildfacts/crustacea/crab/ocypodoidea/dotilla.htm.

We also spotted a number of fiddler crabs in the area. Third 'discovery' is one of them (picture below).
Discovery Note:
1. Fiddler crabs are characterised by their one oversized pincer.
2. Do take note that only the males have this oversized pincer.
3. The purpose of it is to attract mates and sometimes used to 'fight' for terriotry.
4. However, the oversized pincer is useless for feeding, they use their normal-sized (small) pincers to feed.
5. Female fiddler crabs have TWO pincers (small-ones), thus they can feed faster than males.
6. Find out more about the orange fiddler crabs on the wild facts site: http://www.wildsingapore.com/wildfacts/crustacea/crab/ocypodoidea/vocans.htm.

And just near the upper reaches of the sandy shore, we manage to find a few land hermit crabs as well! Fourth 'discovery' is one individual (picture below).Discovery Note:
1. As their name suggests, they are more likely to be found on land, more specifically, the upper shores where they can avoid the waters from high tide.
2. As they have adopted to life out of water, they will drown if kept underwater.
3. It breathes by using special gill chambers which are large and retains water well. This means that they have to go for a occasional dip in rainwater or the sea to keep the gill chambers wet.
4. Read more about the land hermit crab @ http://www.wildsingapore.com/wildfacts/crustacea/othercrust/anomura/hermit/coenobita.htm.

Two related crabs was also spotted amongst the rocks of the inter-tidal zone. The brown egg crab and red egg crab (pictures below). Fifth and sixth 'discovery'.Discovery Note:
1. If you are ever out of food and stuck on an island, never eat this kind of crab, as they are poisonous and their toxins are not destroyed by cooking.
2. Read more about the red-egg crab @ http://www.wildsingapore.com/wildfacts/crustacea/crab/xanthidae/integerrimus.htm.

If you have noticed, I have written about a few crustaceans already and here's one more, the snapping shrimp, seventh 'discovery' (picture below).Discovery Note:
1. If you have walked around the inter-tidal zones and wondered what is making a 'click' or snapping sound, this is it!
2. They make this sound to stun prey, ward off predators or intimidate other snapping shrimps.
3. Read more about them @ http://www.wildsingapore.com/wildfacts/crustacea/othercrust/shrimp/alpheidae.htm.

Extra:
If you are interested to learn more about crustaceans, visit http://www.wildsingapore.com/wildfacts/crustacea/crustacea.htm to have a general idea of what they are.

Eighth 'discovery' is an onch which can be found on rocks on the high shores (picture below).
Discovery Note:
1. Although located near the seas, they actually belong to the same group of animals as land snails!
2. For breathing, they have lungs instead of gills! Thus at high tide, they burrow into mud or sand and trap an air bubble to breathe from.
3. They are actually quite common but well camouflaged, so take a closer look next time you pass a rock near the seas during low-tide.
4. Read more about them @ http://www.wildsingapore.com/wildfacts/mollusca/slugs/onchididae/onchididae.htm.

R also found an seldomly seen nudibranch. This should be a spotted foot nudibranch (Discodoris lilacina). Ninth 'discovery' (picture below). Discovery Note:
1. See more pictures of this sea slug @ http://www.wildsingapore.com/wildfacts/mollusca/slugs/nudibranchia/lilacina.htm.

The tenth 'discovery' of the day and the last one for this entry is blue-spotted fantail ray spotted by G (picture below).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. It 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.
6. Read more about them @ http://www.wildsingapore.com/wildfacts/vertebrates/fish/dasyatidae/lymma.htm.
Another nice trip with the company of friends and creatures of the sea, thanks to LK for organising this trip. ^^

Thursday, November 27, 2008

Semakau Inter-Tidal Walk on 27 Nov 2008

Eighty-First Discovery Posting:

Today, together with a group of students from NUS high, we 'swam' around the inter-tidal area of Semakau.

Why swim? That's because we were 'puffer fishes'. hahaha... Puffer Fish was our group name la (in Singlish terms).

Anyway, they were there today as part of the training for Project Semakau (a three year project to collect data on Semakau)

More information of this project can be found on: http://projectsemakau.rafflesmuseum.net/

So, after a long foreword or whatever the above is called, let's get down to our first 'discovery' of the day, the common sea star (picture below).

Discovery Note:

1. Their tube feet are interesting as they are used for walking, handle food as well as breathing, and probably to catch prey as well, talk about multi purpose!
2.
Sea stars get stressed when out of water, this is because while we have blood circulating our bodies, they have sea water circulating their bodies.

3.
They are not as common as their name suggests. This is due to past over-collection and habitat lost past and present. So don't take them away from their homes when you see them. =)
4. Some sea stars are predators that prey on worms, crustaceans and bivalves while some are known to eat decayed plant matters.
5. Many sea stars eat with their stomach outside their body. When doing this, their tube feet will pull the two shells of a bivalve apart. And while still attached to their prey’s body, they extend their stomach out through their mouths into the bivalve shell.

6. Read more about the common sea star on http://www.wildsingapore.com/wildfacts/echinodermata/asteroidea/archaster.htm.


The second 'discovery' was spotted as we crossed the seagrass meadows, a synaptid sea cucumber (picture below).
Discovery Note:
1. This looks very different to the sea cucumbers you usually see.
2. Synaptid sea cucumbers don't have tube feet. Instead, they may stick to things with their hooked spicules which poke out of their soft bodies. This is why they stick to our hands if we touch them.
3. They have thin body walls and are fragile, so we should not handle them.

Well, a group photo along the trail through the seagrass meadow seems to be norm nowadays, so here's one (picture below).
Third 'discovery' is this yet-to-be ID-ed sea star. We have been seeing this for the last few trips since it was first spotted. Hopefully, it will be there to greet us everything we visit the area =) (picture below)Fourth 'discovery' is a spider conch (picture below)!
Discovery Note:
1. This is often overlooked as its topside is well camouflaged.
2. Their movement is like a pole-value action sequence. They make use of a curved, knife-shaped operculum attached to a long strong foot to 'hop' around.
3. They are listed among the threaten animals of Singapore due to development and over collection.
4. Read more about the spider conch on http://www.wildsingapore.com/wildfacts/mollusca/gastropoda/strombidae/lambis.htm.

Our hunter seekers today either had great sight or good luck or even both, as they found us two knobbly sea stars of different sizes! Fifth 'discovery' (picture below).
Discovery Note:
1. Although they are often brightly coloured and covered with dangerous-looking knobs, nodules and spines, Knobbly sea stars are not venomous.
2. As they can grow up to a diameter of about 30cm, they are considered highlights for inter-tidal walks.
3. Read more about the knobbly sea star on http://www.wildsingapore.com/wildfacts/echinodermata/asteroidea/protoreaster.htm.

And here's the traditional group photos with them (pictures below)
And here's one puffer fish who is attempting to kiss one of the knobbly sea star. I must say this must be the first time I saw anyone attempting to kiss one of these... haha... (picture below)And of course, evening walks are accompanied by sunsets (picture below).Here's the sixth 'discovery', a bohol nudibranch, Discodoris boholiensis (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.

4. To protect themselves, some produce distasteful substances, toxins and even acids. They advertise this with bright warning colours. Others are camouflaged to match their surroundings. Those that eat colourful creatures such as sponges or corals, may themselves be colourful to match their prey. Being small and flat, they can also easily hide in narrow places.

5. Read more about the bohol nudibranch on http://www.wildsingapore.com/wildfacts/mollusca/slugs/nudibranchia/boholiensis.htm.


And as we walked back, we also came across a juvenile knobbly sea star! Wow (picture below)!
Here's another photo as we cross the seagrass meadow on the way back (picture below). The picture is a bit bright due to the settings on my camera.Here's an attempt on an 'artistic photo of our shadows (picture below). =PAnd a photo from near the NEA building of the sunset and the mini bus going to pick up the rest of the groups at the entrance of the forest trail (picture below).And a final group photo (picture below). Puffer Fishes, Puff Up! hahaha... Here's a BIG Thanks to all puffer fishes from me, you people were attentive and a great group! =D

Saturday, November 15, 2008

Semakau has another Star!

Number Eighty Discovery Posting:

Together with a group of HSBC green volunteers and volunteers from NUS, NTU and other schools, we were at Semakau today for a transect training session to help everyone to familiarize ourselves with the ways we would use to do transects.

Well, looking at the title of this blog entry, you might be wondering which star would it be? Well, we have not managed to ID the 'new' seastar we saw yesterday (I heard from SY and PY that they saw the 'new' star again today, will await for their blog entries =D ). Anyway...

The star of this blog entry is shown below:
Here's a closer look (picture below)Its underside (picture below)Could this seastar be a juvenille Pentaceraster mammilatus (the newly discovered seastar on Cryene Reefs just this year)? Or could this be another species of Pentaceraster? No matter what, this is a GREAT find!

To compare, you can find some pictures of the Pentaceraster mammilatus on http://www.wildsingapore.com/wildfacts/echinodermata/asteroidea/pentaceraster.htm.

To top this up, we also sighted a number of knobby sea stars. Here's one of them (picture below)And the more exciting part is that we saw at least around 7 of them (juvenilles!) amongst or near the seagrass meadows. Could Semakau be like Cyrene were there are a number of juvenille knobbly sea stars? If yes, it might mean more work for Star Trackers but nevertheless very exciting news for all!

Here are some of them (pictures below):Don't they look cute? Or is it just me...hehehe.

Friday, November 14, 2008

A New Star Discovery???

Seventy Ninth Discovery Posting:

I believe that nature lovers share a common reaction of being overly excited when seeing something that you have only seen before in books or encountering something you have never seen or came across before.

This evening, over at Semakau, I belonged to the second group: I encountered something which I have NEVER seen or came across before. Therefore, I was really excited!

What was this 'thing' that cause this reaction from me? It's a sea star!

Pictures of it is found below:
I have never came across this seastar in the little books about seastars I read or seen...

Another photo of it (below):Could it be a knobbly sea star because of its knobs?
Or could it be another kind of Pentaceraster sea star?
A wild guess might be a cushion star as its pattern close up really looks like a cusion star's...

A closer look... (picture below)
Can this mean another new discovery for Singapore? Wow! It would be great! Can anyone help to ID this 'new discovery' of mine?

The underside of the seastar (picture below):Just to clarify, this seastar was not spotted by me, but by ST, so if this was a NEW species, there might be a possibility that it would be named after him! =P

After looking a little (really a little) online, this could be a knobbly sea star.
Refer to http://www.wildsingapore.com/wildfacts/echinodermata/asteroidea/protoreaster.htm
Scroll all the way down to the bottom right picture... hmmm...

But there still lies a possiblitiy that this might be a new find for Singapore!!!

Extra information:
a) See photos of the Pentaceraster Sea Star: http://www.wildsingapore.com/wildfacts/echinodermata/asteroidea/pentaceraster.htm

b) See photos of some cushion stars: http://www.wildsingapore.com/wildfacts/echinodermata/asteroidea/culcita.htm

Extra Links:
a) Read ST's blog entry on this very same star!

b) Read Tidechaser's blog entry on this walk.

Thursday, November 6, 2008

Semakau Inter-Tidal Walk on 1 Nov 2008

Seventy Eighth Discovery Posting:

This is an overdue and late posting for the Semakau Inter-Tidal Walk with HSBC volunteers over the last Saturday. It's late as I was busy planning and typing projects and reports, well, better late than never... haha

Oh ya, regular discoverers might have noticed the change of template for my blog. A more simple theme was my target this time, and so I present to all 'discoverers' this new template (which I grabbed from online somewhere)...

Anyway, down to this posting...

As mentioned above, it was a day out with HSBC volunteers, but I wasn't really guiding. Why? This was supposed to be a practice session for HSBC volunteers to test their own guiding skills and knowledge of inter-tidal organisms.

So here's a pre-walk group photo (picture below) outside the NEA building.
After walking through the forest, the 'show' begun. Here's one 'arrowed' lead guide doing her job (picture below). What was she showing us? First 'Discovery'! A fiddler crab, if i'm not wrong, this is orange fiddler crab (picture below).Discovery Note:
1. Fiddler crabs are characterised by their one oversized pincer.
2. Do take note that only the males have this oversized pincer.
3. The purpose of it is to attract mates and sometimes used to 'fight' for terriotry.
4. However, the oversized pincer is useless for feeding, they use their normal-sized (small) pincers to feed.
5. Female fiddler crabs have TWO pincers (small-ones), thus they can feed faster than males.
6. Find out more about the orange fiddler crabs on the wild facts site: http://www.wildsingapore.com/wildfacts/crustacea/crab/ocypodoidea/vocans.htm.

We were quite lucky to be able to view the sunset during this evening walk (picture below).
Of course, any guided walk would include group photos with beautiful scenery (picture below). Oh ya, I forgot to mention that we were nemos (clownfish) for the day. Our second 'discovery' was a sandfish or also called garlic bread sea cucumber (picture below).
Discovery Note:
1. The popular Chinese name for sea cucumber is haishen, which means, roughly, ginseng of the sea.
2. This particular sea cucumber is one of the species which is collected as a Chinese delicacy.
3. Tests have shown they contain toxis, thus they MUST be properly processed before they can be eaten.
4. Find out more about this sea cucumber on http://www.wildsingapore.com/wildfacts/echinodermata/holothuroidea/scabra.htm.

Can't resist snapping away at the sunset (picture below)...

Here's another 'arrowed' guide doing her 'work'. By the way, she was talking about the mating behaviour of common sea stars. Oh yes, this is ... third 'discovery' (picture below).
Discovery Note:
1. Common sea stars have an interesting mating behaviour
2. The sea star on top, a male, lies on top of the female, his arm alternating with hers as seen in the picture.
3. Their reproductive organs do not actually meet as they have interior reproduction organs.
4. What happens is that they will release sperms and eggs almost at the same time.
5. This behaviour they have is believed to increase the chances of external fertilization.
6. Find out more about the common sea star at http://www.wildsingapore.com/wildfacts/echinodermata/asteroidea/archaster.htm.

Look at this...wow... (picture below)Fourth 'discovery' is a persian carpet flatworm (picture below). My first decent photo of it. =)Discovery Note:
1. Flatworms are hermaphrodite, which mean they have both the male and female sex organs.
2. One interesting thing about some species of flatworms is that when two individuals come together to mate, they will engage in a fight, trying to pierce the skin of the other with their penises (bear in mind that they are hermaphrodites). The first to succeed 'poking' the other inseminates the other, which must then carry and nourish the eggs. We usually call the fight process, penis fencing.
3. Anyway, find out more about this flatworm on http://www.wildsingapore.com/wildfacts/worm/polycladida/bedfordi.htm.

Now what are they looking at this station (picture below)?

Oh, a bohol nudibranch (picture below). Fifth 'discovery'.

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.

To protect themselves, some produce distasteful substances, toxins and even acids. They advertise this with bright warning colours. Others are camouflaged to match their surroundings. Those that eat colourful creatures such as sponges or corals, may themselves be colourful to match their prey. Being small and flat, they can also easily hide in narrow places.

4. Find out more about this nudibranch at http://www.wildsingapore.com/wildfacts/mollusca/slugs/nudibranchia/boholiensis.htm.


Lastly, the sixth 'discovery', a hairy crab (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!

4. Do bear in mind that these are not the same 'hairy crabs' served in restaurants.

5. Find out more about hairy crabs at http://www.wildsingapore.com/wildfacts/crustacea/crab/pilumnidae/pilumnidae.htm.


Thanks to all nemos for making this trip another enjoyable one and I do apologize for that late posting. =D

Wednesday, October 29, 2008

Discover about Global Dimming

Seventy Seventh Discovery Posting:

This is the first posting on a more general environmental issue: Global Dimming.

The rational behind this posting is that this is something new which I had discovered, and you might be wondering how is this related to any environmental issue.

Think global warming.

Here's a spoiler, it has to do with the sun as well.

Anyway, I don't believe I can present this topic better than the video which I learned about global dimming from. Another reason why I chose to embed this video (below) is because the introduction and discussion of this issue was done quite comprehensively (personal opinion) in this video.

For your information, the embedded video is a program on Global Dimming from "BBC: Horizons" and lasts about 45 minutes.



If you find that you do not have 45 minutes to spare to learn about global dimming, visit this link: http://www.bbc.co.uk/sn/tvradio/programmes/horizon/dimming_prog_summary.shtml to read a summary of the video.

Enjoy the video, discoverers.

Do give some thought to the issue of global dimming after watching or reading about it. =)

Monday, October 20, 2008

Semakau Inter-Tidal Walk on 18 Oct 2008

Seventy Sixth Discovery Posting

It was an evening out with a group of 'turtles' from the HSBC volunteer group. Here's a group photo of all of us before the walk (photo below).
Although it looked clear and blue at the point of time when we took this photo, it was actually raining quite heavily as we headed off from Marina South Pier. However, the rain stopped as we started our walk, thus, I must say we were quite lucky. =)

Anyway, our first 'discovery' is this pair of moon crabs (picture below).
Discovery Note:
1. If you look closer, you will find that all the walking legs of the moon crab is of a paddle-shape.
2. This enables the moon crab to swim, and more interestingly, use its legs as 'spades' to quickly bury itself in soft sediments.
3. As they are often buried in the sediments, one don't see them very often.
4. Read more about them @ http://www.wildsingapore.com/chekjawa/text/g323.htm

Close by, we saw a really cute juvenile squid (picture below). Second 'discovery'!
Discovery Note:
1. Squids are Cephalopods like octopuses and cuttlefishes.
2. This means that they are able to change their colours on their surfaces in an instant for camouflage purposes.
3. Do you know that squids are amongst the fastest aquatic invertebrates? Some of them can reach speeds of up to 40km per hour!
4. Stay Tuned for more facts on the squid on my next blog posting =P

The third 'discovery' was a find by one sharp-eyed 'turtle'. And this was something I never saw before. After some asking around, I managed to find out that this is a kind of headshield slug (picture below).
Discovery Note:
1. According to observation and some help, the ID of this headshield slug might be Philinopsis pilsbryi.

The fourth 'discovery' is the stars of the seas (common sea stars). Here they are in an interesting position (picture below). Read on to find out more...
Discovery Note:
1. This is actually a mating behaviour of the common sea stars.
2. The sea star on top, a male, lies on top of the female, his arm alternating with hers as seen in the picture.
3. Their reproductive organs do not actually meet as they have interior reproduction organs.
4. What happens is that they will release sperms and eggs almost at the same time.
5. This behaviour they have is believed to increase the chances of external fertilization.

It was another great day out, as the 'turtles' were an attentive group. Thanks, everyone! =)