Snakey and Galloping National Day at Semakau

This morning's trip brings us to a corner of Semakau intertidal area less explored. Some of the team members are excited about this trip because of some special animals that was sighted on this shore. One of them is the Galloping seastar (Stellaster equestris).

I have never seen a galloping seastar before and I was not expecting myself to be the one to find the galloping seastar at Semakau this morning, but I did!

Galloping seastar, overview

Shouting "Galloping!" out loud on the shore, many of the team members came from all directions and distances to see this amazing seastar. Kok Sheng was the fastest walker amongst them all as this was what he was looking forward to on this trip.
This is how pretty the galloping seastar is.

Close up

Details on arm

Underside

Close up of oral disk

I started of the trip with sighting of 2 False clown anemonefish (Amphiprion ocellaris) on one of the numerous Giant carpet anemone (Stichodactyla gigantea). One of them gave me a short peak before going into hiding in the anemone.

False clown anemone fish peaking at me

Only showing its tail for me

Chay Hoon finds a Masked burrowing crab (Gomeza sp.). The crab is about the size of our thumb and it was very active to make it stay very still to get photos of it.

Gomeza crab, overview

Gomeza crab, underside

Finally, I managed to get two images of the Red ribbon worm before it retracted slowly into its burrow.

There was also a few Upsidedown jellyfish (Cassiopea sp.), some in upright position.

Bell of the jellyfish

Upsidedown jellyfish tentacles

Closer look at the tentacles

The tentacles look very much like the Fire anemone (Actinodendron sp.) but they actually look very different.

Fire anemone

White stripes and small dark spots radiating on the oral disk

Tentacles with clusters of oval tips

I also had great snakey encounters with two types of snakes - a Dog-faced watersnake (Cerberus rynchops) and a Banded file snake (Acrochordus granulatus). 

The dog-faced watersnake is mildly venomous but it is a very gentle animal which we were able to get up close with it. 

Dog-faced watersnake

Front profile

Left profile

On the other hand, the Banded file snake is non-venomous and harmless to humans. However, during the trip, I thought it was a sea krait was approaching the snake with great cautions.

Head of Banded file snake

Banded file snake about to check out a burrow.

Tail of Banded file snake

Here is a video of the snake trying to hunt as it seeks burrows to look for food.

As we were about to end our trip, I found a Lined moon snail (Natica lineata).

Lined moon snail, underside

Overview, pretty lines

The team was treated to great sunrise this morning on the shore of Semakau.

Panorama of the shore on Semakau with sunrise

To celebrate Singapore's National Day (today), the team had small handheld flags that we were able to bring it with us to shore easily. I did a series of photographs to capture some of our marine biodiversity on this 48th National Day.

From the Semakau shore

From the Common seastar

From the Tape seagrass

From the Knobbly seastar
(many suggested 5 seastar, but we couldn't find another two to fill the picture)

From the juvenile knobbly seastar

From the Astropecten seastar

Unfortunately, it was not a happy trip thoughout. Ria and Kok Sheng came across driftnets on this trip which entangled many marine animals such as horseshoe crabs, blue-spotted fantail rays, sharks and fish. Read more about the diftnet sighting from Project Driftnet's blog post.

This is one of the shores that I would look forward to visit again.

Read about posts by others on this trip:
Kok Sheng - National Day field trip at Pulau Semakau
Ria - Celebrating National Day at Pulau Semakau

Cyrene Reef - Land of Sea Stars

I had my first step onto Cyrene reef today.
Cyrene is a submerged reef located in an industrial triangle consisting of Pasir Panjang container terminals on the mainland, petrochemical plants on Jurong Island and Pulau Bukom.

Image from WildSingapore

Pasir Panjang Container Terminal

Pulau Bukom

For submerged reef, there is no proper jetty or docking place for boats to stop. Luckily, we just have to transfer to a dinghy from the main boat to get to the reef.

Like yesterday, I got up early for the 06:00 meeting time at Marina at Keppel Bay. I was my first time setting off from a marina. When we set off, the sky was barely lighting up. The morning sky was really nice as we set sail to our destination. There were pretty streaks of light form from the rising sun.

As we set foot on the reef, the sun slowly showed itself.

The objective of this trip was to remove the stakes from Siti's experiment. On Friday, another team had already removed and smashed the structures. It was a quick task removing the heavily corroded stakes and we got more time to check out the reef. Yay!

While walking to the seagrass experiment area, we came across a group of white sea urchins (Salmacis sp.). Ria was wondering if the different coloured spines represent different species of the white sea urchin.

White sea urchin cluster

White sea urchin with different coloured spines

I later found a cute tiny sea urchin.

Tiny sea urchin with pink spines.

We also came across a grey bonnet snail (Phalium glaucum).

Grey bonnet snail (Phalium glaucum)

Looks like someone else had arrived on this reef earlier than us.

Feather visitor

I only managed to cover a section the pasir panjang side of the reef, where the knobbly sea stars are located.
There were many plain frilly anemone (Phymanthus sp.)located on the sand.

Frilly anemone out of water

Frilly anemone in water

And also other kind of anemones.

Unknown anemone

Fan worm

It's my first time seeing a swimming anemone (Boloceroides mcmurrichi). There were many of them around after I saw my first swimming anemone.

Swimming anemone

 

I also saw a few types of sea cucumber.

Unknown short sea cucumber

Black long sea cucumber (Holothuria leucospilota)

Garlic bread sea cucumber (Holothuria scabra)

There were crabs of interesting kind, some of which it is my first time seeing it.

Elbow crab (Family Parthenopidae)

Very well decorated Arrow-head spider crab (Menatheius sp.)

There were two puzzling crabs seen.
The first crab can be found in almost very coral rubble bit. They create a hole in the dead coral and its tiny body carries it around. It is amazing how this small crab can mange to move such a large coral.

The tiny crab has a deep shelter to hide when the coral is flipped over.

Tiny crab slowly emerging.

Here's a video of the crab:

 

Another unknown crab is this one which I found clinging onto a sponge next to a carpet anemone.

It was suspicious to find a difficult to lift piece of sponge next to the anemone. After some tugging, it reveals a crab holding onto the sponge. I have no idea what crab it is. As I tried to coax the crab out of the sand, it went deeper below the carpet anemone, clinging onto something else tightly in the sand. Could it be some kind of sponge crab?

Crab view 1

Crab view 2 (it "threw" the sponge onto the anemone)

Crab view 3

I found one black-margined nudibrach (Glossodoris atromarginata).

Black-margined nudibranch

Chay Hoon found a melibe nudibranch (Melibe viridis) and they seem to be in season now. I couldn't find any though.

I name Cyrene reef the land of sea stars as there are many sea stars on this reef. Large in numbers are the knobbly sea stars (Protoreaster nodosus) and the common sea star (Archaster typicus).
The large knobbly sea stars were seen in groups and they come in various arm numbers, size and colours.

5 knobbly sea stars here and many more around

4 armed

6 armed knobbly

Underside of a knobbly sea star

Damaged arm will regenerate on its own.

 

There is almost a pool of common sea star in various positions.

Mating position 1

Exposed mating position

Signs of common sea star burrowing

4 armed

Soon it was time to go as everyone made their way to the drop off point on the sand bar waiting for the dinghy to come and pick us batch by batch.

Cyrene reef is really huge and it will take me a few visits to finish one full round. I must say that Cyrene reef is one of my favourite place to visit now. Looking forward to the predawn trip to Cyrene in July.

For now, school term for semester 2 will begin tomorrow and I will start to get busy with school work. However I will still find time to visit the shores. Stay tune.

Read more about what others saw during this trip:
Ria Tan shares her anemone sightings
Sankar shares about his trip to Cyrene