Special snails and strange worms on Changi

4am and we're on Changi! How wonderful to see this thriving shore after having seen the one on the East Coast!

Here's some of the stuff I thought was special. This morning was the first time I saw a living murex snail! This is probably the Rare spined murex (Murex trapa) which is listed among Singapore's threatened animals.It has a long muscular foot, with the tear-drop shaped operculum attached to it which is the 'door' that seals the shell open when the animal retracts.The snail tucks the operculum upwards when it sticks its narrow foot into the soft ground. You can also see the very long eye 'tentacles' that the snail has.

Further along, I saw another living murex which had something clutched its narrow foot.A closer look reveals that its prey is some kind of clam.I'm not sure if the bluish colour is the colour of the clam shell or due to something that the murex shell was doing to the clam.

Just a few steps onto the shore and Chay Hoon spots this sea cucumber... no, wait ... sea anemone... err ... wat IS it?! It was only after we saw the spoon shaped thing on one end of this tubular animal in pajamas, that we realised it was a spoon worm or echiuran (Class Echiura, Phylum Annelida). A spoon worm has a spoon-thing, called a protomium, is found in front of the mouth. The protomium can extend up to 10 times its retracted length, in some species, reaching 2m long! In most, the protomium is used to gather edible bits from the surface.

Many live in U-shaped burrows in shallow water, others in rock or coral crevices. Apparently, echiurans may be important food for some fishes. In a study of Leopard sharks off California, large, meaty spoon worms were found to be their favourite food.

Here's a drawing of a burrowing echiuran called the Landlord worm found in the U.S. east coast (Taken from Barnes' Invertebrate Zoology). Apparently, its burrow is so comfy that tiny clams and crabs quickly settle in with the worm.

I wonder what our spoonworm does? Lots more to find out about our shores!

Here's some tubular stuff that look similar to the echiuran.A peacock anemone retracted into its tube on the lower left, and a long smooth sea cucumber diagonally across the photo.

Another strange worm-like thing was this one.Here's a closer look at the icky, stringy parts on the front of it.Is the smooth pink worm with the yellow hair things eating the segmented bristley worm?

The pink worm looks quite similar to something Marcus found yesterday, also at Changi.It was quite scary looking with lots of transparent strings and a coiling yellow portion.

These worms with strings might be terebellids (Family Terebellidae, Class Polychaeta, Phylum Annelida). These burrowing worms are also called spaghetti worms because the stringy long tentacles on their heads are all that is often seen above ground. Here's more about terebellids on the Polychaetes of Singapore website.

Changi is among the few places where you can be almost certain to see the fascinating black phoronid worms (Phylum Phoronida) that cluster around peacock anemones.This is the largest cluster of phoronid worms that I've seen so far. Kok Sheng spotted it and we both had to sneak up gently to them to avoid scaring them into retraction.I think these delicate spiral pink-and-black feathery worms are very elegant!

Seahorses are so commonly encountered on Changi that we have taken them for granted.Those seen on Changi are often bright orange or even reddish. We saw three seahorses today.Unfortunately, one of them seemed to have suffered some sort of laceration across the body.

The shore has much debris, abandoned fishing lines and even this very large abandoned drift net.In fact, Chay Hoon spent quite some time freeing a horseshoe crab that was trapped in an abandoned net. And she did it without scissors! She improvised and used a clam shell!

Hopefully there will be more love and care of these wonderful Changi shores. So that Changi does not suffer the fate of the shore that we abandoned at the East Coast this morning.

We also saw lots of special sea stars today. Here's more about those stars and other special encounters on Kok Sheng's wonderful creations blog.

Kiasi Krab revisited at Changi

We came across this beautiful sea anemone on Changi. Next to it, a cluster of tiny yellow yet-to-hatch snail egg capsules. These turn out to be attached to a shell occupied by a hermit! The hermit crab is really small because it can disappear completely into its shell. All I could see was the tip of a tiny leg. It refused to come out. It certainly is a lot smaller than the giant sea anemone on its shell.

So why should this hermit crab be so 'kiasi'*? and carry such a huge burden around.

Well, one of the theories is that the sea anemone protects the hermit crab from octopuses. And there were indeed many octopuses on the shores this morning! We saw at least 5 of them out and about in the small area where these hermit crabs are found.

While the sea anemone protects the hermit crab, it might in turn benefit by sharing the leftovers of the hermit crabs meals.

In fact, a hermit crab shell is a great place to stay on. And many other kinds of animals do so.
This hermit crab was found further away from the Octopus Zone and it didn't have anemones on its shell. But inside its shell it had several white Slipper snails (Crepidula sp.)Slipper snails are gastropods (not bivalves). Often the smaller male will settle on top of a larger female snail.

On the other side of the shell were other stuff. Circular things with holes, and just plain holes in the shells.I'm not really sure what these are.

On the other side of the shell was also a chiton!Chitons are molluscs (Class Polyplacophora) which have an armour of overlapping shelly plates over their bodies.

It's clear empty shells are needed by a wide range of animals.

This is something to think about when we want to remove a shell from the shore.

From The Coxford Singlish Dictionary on TalkingCock.com
*KIASI (kee-ah-see) Hokkien term literally meaning, "afraid of death". Used to admonish someone for being cowardly. "Raining only, cannot go out, meh? Why you so kiasi one?"

Changi: A closer look

3am and we're on Changi for the last of this year's morning spring low tides. We've learnt that it pays to take a closer look when out on the shores.This patch of shore may look boring at first glance, but it has lots of interesting animals! Can you see at least four of them? OK, the photo is rather low res.There was a mantis shrimp at the top left corner. This hunter has snazzy fold-up pincers that resemble the arms of the more familiar insect, the praying mantis. It's not a true shrimp and belongs to a separate Order Stomatopoda.In the middle is a living Gong gong (Strombus canarium), its pair of eyes on stalks sticking out from under the well camouflaged shell.On either side of the snail, the tiniest little Striped hermit crab (Clibanarius sp.) that I've seen. And a tiny scorpion fish, probably Paracentropogon longispinis. Indeed we saw lots of fishes today at Changi. Here's more about the fishes we saw today.

Taking a closer look at the many Window pane shells (Placuna sp.) on the shores, I noticed fuzzy stuff on the surface of one.They are the feathery tentacles of keelworms (Family Serpulidae) that settled on the shell!Here's a closer look at another bunch of keelworms that settled on a log on the shore.Hard surfaces also provide a place for animals such as hydroids to settle.Although they look like colourful plants, these are actually colonies of tiny animals.Here's a closer look at the individual polyps that make up the colony.And another look.

I also came across a strange looking sea anemone.After I took a close look, I realised it had much longer tentacles!But these were so transparent I nearly missed them!

Even large animals are well hidden! Such as the ghost crabs!The ghost crabs (Ocypode cerathophthalmus) come out of their burrows at night but it appears, even when they are out hunting on the shores, they can skulk half buried in the sand!Ghost crabs move really fast!Here's one that's settled down to let us take a photo of it.

Today the tide was really low so we could venture out quite far. Where we saw a Bailer snail (Melo melo)!In our explorations, we have only seen this snail regularly at Beting Bronok. It's nice to see it also on Changi.

We also saw lots of sea cucumbers today, as well as other echinoderms. More about these sightings.

Also seen today, several small carpet anemones (Stichodactyla sp.), lots of big white sea urchins (Salmacis sp.), a large Peacock sole (Pardachirus pavoninus) in deeper water, some moon crabs, lots of swimming crabs of all sizes, plenty of hermit crabs many with anemones on their shells, many 'pencil' sea pens, and many active moon snails (mostly Polinices didyma).

Missing today: big peacock anemones (Order Ceriantharia) (there were a few of the smaller kind), button snail shells (Umbonium vestiarum).

Fishes at Changi

There were lots of tiny little fishes among the seagrasses at Changi this morning.A really tiny butterflyfish! It's probably a Kite butterflyfish (Parachaetodon ocellatus).A miniscule filefish (Family Monacanthidae) with an even tinier nearly transparent fish swimming above it. Only its golden eyes are obvious!Another tiny black fish. I have no idea what it is. It was too tiny and moving about too much to take a good shot of.

Of course Changi has other fabulous fishes that are larger, but still require a keen eye to spot. These were all found by Master Seeker Chay Hoon.A rather large seahorse that's hairy (Hippocampus kuda).A beautiful Feathery filefish (Chaetodermis penicilligerus).This is probably a fang-blenny (Family Blennidae).

And several fishes that I have no idea of their identity. This is probably a flathead (Family Platycephalidae) although it's not very flat.And another flathead.And this odd little fish with a pair of bristles under its chin.

Seagrass meadows such as those on Changi are a nursery for baby fishes. Some of which are important species to fishermen. Among those seen today were Rabbitfishes (Family Siganidae) and this perch, probably Pelates quadrilineatus .There were also lots of prawns among the seagrasses.

Conserving seagrasses at nearby Chek Jawa and Pulau Sekudu will allow everyone to enjoy fishes and other marinelife. Protected seagrasses provide a safe place for young fishes to grow up and populate the surrounding waters.

Curious Cucumbers of Changi

This morning, we seemed to have encountered quite a few strange sea cucumbers on Changi. Although the common name is sea cucumber, these are animals and not vegetables. They belong to Phylum Echinodermata which includes sea stars, sea urchins, sand dollars and feather stars.Marcus found this cuke. This is the second time we've seen it, the first time also on Changi. It has an obvious underside and not very long tube feet.

Robin was very interested in having a look at it, but we didn't find it when we went with him. At first, I thought the sea cucumber above was a 'cleaned up' version of the sea cucumber below. But when we went sea cucumber searching with Robin a few months ago, he pointed out that this 'sandy' sea cucumber is not covered with sand. It actually resembles sand in texture and colour!And here was another strange sea cucumber tucked up against a Window pane shell and other debris. It had really long tube feet arranged in rows along the body.And YET another sea cucumber that I can't recognise. It seems to have its long tube feet in rows along the length of the body.There was this elongated sea cucumber with tube feet all over the body. It was very active, moving about in the water, stretching out and contracting. I'm not sure if it's a rather active Ball sea cucumber (Phyllophorus sp.) or some other kind of sea cucumber.Of course, there were lots Thorny sea cucumbers (Colochirus quadrangularis) which have soft 'thorns' on the upperside and a distinct underside with rows of little red tube feet.Less commonly seen is the Warty sea cucumber (Cercodemas anceps). Also seen were lots of ball sea cucumbers buried in the sand bars (Phyllophorus sp.) together with smooth sea cucumbers. As well as one Sandfish sea cucumber (Holothuria scabra).

Changi is a great site for echinoderms!

Today we saw more sand dollars than usual. Usually, we see only a handful. But today, there were quite a few close to one another on several parts of the shores.There were lots of sand stars (Astropecten sp.) of various sizes.And one star with only one complete arm!
There were also tiny ones with a different pattern.
Several of them actually.And here's another one.
We will await Kok Sheng's study to find out whether these sea stars are different species or just different patterns of the same species.

If anyone has ideas of about the identities of these animals, please do share. Constructive views are always welcomed so that we together we can learn more about our shores.

Kok Sheng saw even more splendid stars today at a different part of Changi! More on his wonderful creations blog.