The WOW shore exploration

After an exploration of a new shore during a not-so-low tide, this time a small team of us managed to come back during an extreme low tide. It wasn't easy getting to the shore but we were glad we eventually did because there were many WOW surprises waiting for us.

This shore is VERY soft as Andy once sank knee deep the last time he came. That happened to me too! However, the super low tide revealed a section of hard sand that we could stepped on and off we go to the low water level mark to explore for the first time! The area was quite extensive. Wow.


On the sandflat facing the sea are many adult Haddon's carpet anemones (Stichodactyla haddoni) including this anemone in a pretty purple colour, like the ones you can find in Chek Jawa.


There are carpet anemones in other shades of green too and this one even a pair of anemone shrimps living on it.


These Commensal shrimps are probably Periclimenes sp. and they listed as 'Vulnerable' on the Red List of threatened animals of Singapore due to collection for the aquarium trade.


Other anemones spotted include several of these plain sea anemones.


And this sea anemone that I've no idea of it's identification.


There are also many peacock anemones (Order Ceriantharia) in different colours. We also found an orange peacock anemone with phoronid worms.


As seen from my previous trip during a not so low tide, finally I got to see the clumps of tape seagrasses (Enhalus acoroides) with many snails and sea cucumbers on it.

There was also a patch of spoon seagrass (Halophila ovalis) and needle seagrass (Halodule sp.) nearby with plenty of living snails.


The snails include the intricate looking Dubious nerites (Clithon oualaniensis) and creeper snails.


There are also plenty of sea cucumbers on the seagrass area including this orange sea cucumber that is still awaiting for identification.


There are also many thorny sea cucumbers (Colochirus quadrangularis) all over the sandflat and seagrass patches. You can see its filter feeding tentacles out to filter feed plankton and suspended organic particles from the water especially during high tide.


We could also find the not so common warty sea cucumber (Cercodemas anceps). Wow, there's quite a good variety of sea cucumbers already.


Furthermore, we got to find this weird white sea cucumber that we don't know what it is! Wow.


Mei Lin found this ball sea cucumber (Phyllophorus sp.) buried in the sand and she sighted it by it's feeding tentacles above the sand.


And the most WOW discovery of the sea cucumbers there will be the many tiny red sea cucumbers that were common on Chek Jawa and Tuas, in groups of many individuals.

They are about 1cm or shorter. Often mistaken for worms, each has all the features that bigger sea cucumbers have. Tiny long white tube feet emerge along the body length, and are used to cling to the surface.


You can also see from this photograph that their long branched feeding tentacles emerge from the mouth.

I've not seen this sea cucumber before so it's really a wow discovery for me, in addition to its many numbers.


As for sea stars, I found this large painted sand star (Astropecten sp.) on top of the four rare eight-armed sea stars that I've described in a separate post. I also found a tiny biscuit sea star on the sand flat.


How about sand dollars? It is delighting to find many rare Laganum sand dollars (Laganum depressum) that I've never seen before. WOW! They were only reported intertidally before by Ria previously at the Sentosa North shore that has already been buried for IR reclamation.

There are also many of the usual Cake sand dollars at the bottom left of the photograph (Arachnoides placenta).


They come in different shades of pink and they prefer soft and silty sand substrate to live in.


This rare sand dollar has somewhat pentagonal rather than circular shape. On the upperside it is thick at the edges and at the centre, and thinner elsewhere, creating a shallow circular depression around the centre. Spines at the edges of the body are longer.


The underside where the anus can be found, has long spines.

What a wonderful find of rare sand dollars in large numbers at this shore!


On the sand flat is also this juvenile sole fish (Family Cynoglossidae) that swam at the sandy bottom.


There was also this bloody red worm that I've no idea what it is. But it did look like it bleed.


Scurrying on the shore and running away quickly are many of the ghost crabs (Ocypode cerathophthalmus). This particular one did not run away from me because it seems to be feeding on another small crab! Wow.

Soft sandy and silty shore seems to also harbour many molluscs and we found a number of surprising finds at this shore.


Including this live gong gong snail (Strombus canarium) with both eye stalks peering out at me.


There are also snails spotted that are alive instead of the usual dead shells we sighted usually at other shores. This one is possibly a Bufonaria sp. (Family Bursidae).


This is yet another snail with beautiful shell that is ALIVE!


At the high shore, I was wow-ed by the aggregation of snails. There were plenty of space but I don't know why they aggregated like that!

Could they be all dead snails that are inhabitated by hermit crabs? I regret not checking it out more.


The only thing I checked was the button shell that is actually inhabited by a hermit crab.

If the above aggregation were all hermit crabs, then they might be doing a MASSIVE exchange of shells. Wow. With the christmas spirit somemore. Hahaha.


Other than the numerous tiger moon snails (Natica tigrina) encountered, there are also pretty lined moon snails (Natica lineata).

The final WOW of the day must be this snail.


I saw this snail that we all have never seen before! It has a very pretty mantle covering its intricate shell. In addition, it also has a pinkish siphon.


The underside of this snail reveal a orange foot that is oval in shape.


Don't underestimate it's foot because it seems to be rather strong! I heard the ladies said it was doing pushups on the sand. :P

We found several others of this special snail soon after the first sighting.


Great find of this newly sighted snail! Hopefully we can get its identification soon to see if it's a new record in Singapore.

There's so much to explore in our shores of Singapore. Unexplored and hidden shores might have rare and new stuffs that no one can ever imagine. Before they are gone, by coastal development, we really need to take a closer look at the biodiversity of the marine life and know what exactly we have on our waters.

Fascinating eight-armed sea stars

Today while exploring a new shore, we were looking hard for sea stars. Soon, Ria called me over as she found a sea star that is not even common in the first place.


It's the eight-armed sea star (Luidia maculata) that is not commonly sighted! In fact, it is now listed as 'Endangered' on the Red List of threatened animals in Singapore. It was formerly found near the mainland prior to reclamation but recently known only from the Pulau Ubin and Pulau Tekong area in low numbers. Nevertheless, it has even been now found at the intertidal area of Semakau!

According to Lane, it burrows in soft sediments and feeds on small buried animals such as molluscs and other echinoderms.


When we first found this fascinating big sea star of about 30cm in in diameter, it was in this weird "squatting position" with their whitish pointed tube feet hanging downwards.


Taking a look at its underside, there was no prey! Why did this sea star position itself like that? Hmm, I've no idea though unfortunately.


Soon, Ria and Chay Hoon found yet another Luidia sea star!


Taking a closer look at its aboral surface, it seems that this sea star has orange pigments on top of its darker brown pigments. Something a bit different from the usual Luidia maculata we see.


What surprised all of us is that the whitish tube feet each have an orange stripe across which was never observed in any of our previous sightings.

Could this be another Luidia species for Singapore?!


Another interesting thing about this particular star found was that it has a regenerating/generating arm coming out. So it has nine arms! Amazing.


I later found another eight-armed sea star that has also the orange strip on its tube feet.


And the fourth one too, this though doesn't have the orange stripe on its tube feet.

It's fascinating to discover new stuffs from our marine sea stars! And it will be a treat if they are new Luidia records.

Reference:

Lane, David J.W. and Didier Vandenspiegel. 2003. A Guide to Sea Stars and Other Echinoderms of Singapore. Singapore Science Centre. 187pp.

Last 2008 seagrass monitoring at Semakau

After a rainy and wet Semakau trip on Thursday, we were blessed this time with a cloudy and cool weather. Most importantly there was no rain.


I am delighted to be back at the Semakau intertidal area during low tide. This place is so beautiful.

And what is our mission today? We had our last of 2008 Teamseagrass monitoring today at the lush seagrass meadow of Semakau. I was one of the team leader of Site 2 together with Michelle who assisted me a great deal. My team for the transect was with Ian and Alex. Though they are first timers to Semakau, we did a great job measuring and assessing the health of seagrasses.


And within one of our quadrats is a black lipped conch (Strombus urceus)! You can see it's white shell at the top right corner.


After the hard work of monitoring seagrasses in a perpetual soaked area, with our bottoms wet, we got to explore the reef a bit with the remaining time left.


I saw this living scallop, though it's tentacles are not showing out in this photograph.


There was yet another bivalve that is about 2cm in length and unidentified. It has a brown interior though. Could this be a juvenile of any known bivalve or something new altogether?


Talking about molluscs, nudibranchs are also molluscs. They are simply snails without shells. Michelle found this cute pair of juvenile polka nudibranch (Jorunna funebris).


On the reefs, there are many Phymanthus sea anemones and also hard corals that make the reef colourful.


Other hard corals spotted include this White grooved brain coral (probably Symphyllia sp.).


And the neon green faviid coral that I will never get bored looking at because of their attractive colour.


The solitary sunflower mushroom coral (Heliofungia actiniformis) was also spotted in many numbers and they do look very similar to anemones. What was puzzling was that Ian said he saw tomato anemonefishes swimming out from the sunflower mushroom coral and he thought it was an anemone.


My longing to see the stunning tomato anemonefish was fulfilled when Marcus called me out. It's not a common thing for him to call me over, so it must be a special find! Indeed he showed this very pretty green Magnificent anemone (Heteractis magnifica).


The main reason he called to me is that there is a big tomato anemonefish (Amphiprion frenatus) living inside the anemone. Wow!

Marcus added that this anemonefish is very friendly as it will come out for a while if you hover shadows of your hand above the anemone etc. He even showed a photograph he took of the stunning looking anemonefish out of the anemone.

That began my half an hour wait at the anemone! Haha, despite his assurance, the anemonefish refuses to come out as much as it would be.


Throughout the course, I managed to still see the tomato anemonefish looking at me!


It turned a bit to reveal it's black-edged white bar located just behind the head. It feeds on plankton (mostly copepods) and also munches on bottom-dwelling algae.

Unfortunately, these fishes are taken in large numbers from the wild for the aquarium trade. Like other fish and creatures harvested from the wild, most die before they can reach the retailers. Without professional care, most die soon after they are sold. The Tomato anemonefish is listed as 'Vulnerable' on the Red List of threatened animals of Singapore.


Soon, the anemonefish decided to retreat back into the anemone, ending my 30 minutes encounter with this creature. Perhaps it was too stressed after Marcus looked at it in the beginning to come out. Next time then~!


Nevertheless, we also found out that the more commonly sighted False clown anemonefish (Amphiprion ocellaris) is inside this Gigantea carpet anemone. However, this anemonefish is much more shy as compared to the tomato anemonefish. So no photos could be taken.


I later found this Blue-spotted fantail ray (Taeniura lymma) semi hidden in the sand. If you are not careful, you might step on it! It sensed our presence nearby and started to swim away promptly.


The gang also found a seahorse. Great!


There were several sea cucumbers spotted including this stonefish sea cucumber (Actinopyga lecanora).


And this beautiful ocellated sea cucumber (Stichopus ocellatus) that I've only seen at Semakau.


'Ocellatus' means 'having little spots' or 'marked with eyes'. However, these are not real eyes but comprise a large white bump with a dark tip.


There is also the not so common Dragonfish sea cucumber (Stichopus horrens).

Robin and friends found a totally black sea cucumber that is not the usual ones we saw. It is highly likely to be Stichopus herrmanni. Check out Robin's blog on this interesting and big sea cucumber.


The team also found a juvenile knobbly sea star (Protoreaster nodosus) on the sand bank near the seagrass meadows.


Last but not least, I was surprised to witness this large monitor lizard resting on a tidal pool quite far out nearer to the reef edge.

Unfortunately, time passed too fast (especially when I spent most of my time admiring the tomato anemonefish). Couldn't have time to see the other fantastic resident creatures like the giant clam, cushion stars, adult knobbly stars and the weird new star found recently.


Everyone visiting the Semakau intertidal will have to walk through the secondary forest trail that is mossies infested. Haha, thus we had to walk fast fast to try and avoid being bitten. Here's the newly wed Shufen (auntie now already...joking) bringing our team out towards the main road.

What a great day to end our monitoring of the year! I believe most of us enjoyed the marine life and lush seagrass at Semakau. Looking forward for a good 2009 Teamseagrass monitoring next year.