Sunday, June 28, 2009

Semakau over 2 days

I was back at my favourite island, Pulau Semakau, again 2 days in a row. On Friday, it was to help with some Okto TV programme, while on Saturday, I was the coordinator and hunter-seeker.

Friday's trip did not really went on that smoothly, as the TV crew arrived late, and we had to rush through the shooting due to the rising tide and did not managed to see much. Saturday was great though, since the tide was excellent, and I managed to find quite a number of interesting stuff :)

Cushion Star (Culcita novaeguineae)
My top find of the trip must be this huge Cushion Star (Culcita novaeguineae). It's been almost a year since I last saw this particular individual! And frankly, it seemed to have grown even bigger than before, about 30cm wide and quite heavy. It felt like meeting an old friend :)

Tigertail Seahorse (Hippocampus comes)
It took me quite a while to find our resident Tigertail Seahorse (Hippocampus comes). It was a distance away from her usual spot, probably due to the super-low tide. I couldn't find the male though. Guess there were just too much algae around. And how do I know it's a female? It has an ovipositor (fin-like structure below its belly) which it uses to deposit her eggs into the male's pouch. Male seahorses have a brood pouch to hold the eggs before the little seahorses are hatched.

Knobbly Sea Star (Protorester nodosus)
I had to walk quite a distance before I found my first Knobbly Sea Star (Protorester nodosus). And somehow after I found it, the others just started appearing like magic. One of the knobblies had 3 shorter arms - appears that they were chomped off, probably by some predator. The arms are in the process of regeneration though.

Sandfish Sea Cucumber (Holothuria scabra)
I also found this Sandfish Sea Cucumber (Holothuria scabra). This sea cucumber is the one normally found in Chinese restaurant, served as a delicacy. They must be properly processed before they can be consumed though to remove the toxins.

Black Margined Glossodoris Nudibranch (Glossodoris atromarginata)
It was quite a day for nudibranchs! Several were spotted including this Black Margined Glossodoris Nudibranch (Glossodoris atromarginata) which I found on a seaweed.

Chromodoris lineolata
Several Chromodoris lineolata nudibranchs were also spotted. I did not show this particular one to the visitors since the other hunter-seekers had found a few already. The term "nudibranch" means "naked gills", refering to the flower-like gills found on the back of many species.

Phyllidiella nigra
Nudibranchs are sea slugs - basically snails without shells. And the reason they have adapted such that they do not need a shell for protection is that they have developed other defense mechanism. This Black Phyllid Nudibranch (Phyllidiella nigra) is said to be able to secrete toxins to its surrounding when it is stressed. The toxins are so strong that the whole fish tank of fishes can be killed! Helen found one of this nudibranch, while I found another.

Phyllidiella pustulosa
This is a Pustulose Phyllid Nudibranch (Phyllidiella pustulosa), another nudibranch with toxins. Found many of them during the trip, though the one above was found by LK.

Fluted Giant Clam (Tridacna squamosa)
The tide was so low that even our resident Fluted Giant Clam (Tridacna squamosa) was exposed. This is probably the biggest clam species in Singapore, and is able to grow to about 40cm wide.

Hell's Fire Sea Anemone (Actinodendron sp.
I found this Hell's Fire Sea Anemone (Actinodendron sp.) while searching for the knobblies, but unfortunately it was a distance from the main route and being a sessile animal, I couldn't use it for the guided walk. This sea anemone can give very painful stings.

Dragonfish Sea Cucumber (Stichopus horrens)
This little Dragonfish Sea Cucumber (Stichopus horrens) was also found away from the main route, and since LK has already found one, we didn't show it to the visitors too. This sea cucumber has an unusual way to protect itself from predation - by detaching a piece of its skin to distract predators when attacked.

Noble Volute (Cymbiola nobilis)
This Noble Volute (Cymbiola nobilis) was spotted in the seagrass meadow where we usually make the crossing, but only after the visitors had gone back to the washup point. This snail is a predator of clams and other smaller snails. To feed, it wraps its huge foot around its prey in an attempt to suffocate it. When the prey eventually opens up to breathe, the volute will feed on it.

Heart Cockle (Corculum cardissa)
Other hunter-seekers found this Heart Cockle (Corculum cardissa), but it didn't look like it's in a good shape though.

Spider Conch (Lambis lambis)
ST found this Spider Conch (Lambis lambis) near where I found the Sandfish Sea Cucumber. This edible snail is over-collected in some places.

Ocellated Sea Cucumber (Stichopus ocellatus)
Near the reef edge, Helen found this huge Ocellated Sea Cucumber (Stichopus ocellatus). It has lots of 'eyespots' on top, which are believed to have some sensory functions or help the sea cucumber move around and hold to surrounding hard surfaces.

Apart from the above organisms, I also found a pygmy squid, synaptid sea cucumber, while the others also found an upside-down jellyfish, juvenile fluted giant clams and many other interesting stuff.

This was certainly one of my favourite trips so far this year!

Saturday, June 27, 2009

Back to Beting Bronok

The original plan was to visit Raffles Lighthouse, but due to some unforeseen circumstances, we had to change the location to Beting Bronok instead. To be frank, I wasn't really disappointed with the last minute change, but was in fact rather happy as I had not visited Beting Bronok for the past 3 years.

Brown-spotted moray (Gymnothorax reevesii)
We found at least 6 brown-spotted morays (Gymnothorax reevesii), most of them stranded in shallow tidal pools, and two of them were even stranded on dry land due to the low spring tide.

Pencil sea urchin (Prionocidaris sp.)
Pencil sea urchins (Prionocidaris sp.) were quite abundant here.

Knobbly Sea Star (Protorester nodosus)
There is also a good population of knobbly Sea Stars (Protorester nodosus). I saw at least 20 of them.

Cake sea star (Anthenea aspera)
The most delightful star find must be this red cake sea star (Anthenea aspera). While we found several cake sea stars here, this was the prettiest!

Gymnanthenea laevis
We also found a few Gymnanthenea laevis sea stars.

Biscuit sea star (Goniodiscaster scaber)
Like most of our northern shores, the biscuit sea star (Goniodiscaster scaber) can be found in large numbers.

Sand star (Astropecten sp.)
At the sandy areas, many sand stars (Astropecten sp.) were spotted.

Sea cucumber
We have seen this sea cucumber many times on our northern shores, but still has not confirm its ID.

Sandfish sea cucumber (Holothuria scabra)
The sandfish sea cucumber (Holothuria scabra) is another sea cucumber commonly found here. It is also the sea cucumber that you can often find in Chinese restaurants. However, it is actually toxic, and need to be properly processed before they can be consumed.

Haeckeli sea anemone (Actinostephanus haeckeli)
I spotted a Haeckeli sea anemone (Actinostephanus haeckeli). A member of the hell's fire anemone family (Actinodendronidae), this anemone can give very painful stings. I have seen this previously at Changi beach and Semakau, though the one at Changi was green in colour.

Soft coral
One really nice thing about Beting Bronok is that there are lots of pretty soft corals.

Sea pen
The sandy substrate with lots of seagrass and seaweed also means there are lots of sea pens too.

Sea pen
Here's another sea pen. Sea pens are colonial animals with a primary polyp (the middle stalk) and secondary polyps (the feathery bits by the sides of the primary polyp).

Flatworm (Acanthozoon sp.)
Huge flatworms (Acanthozoon sp.) were easily found here, many of which were about the length of my palm, and several were stranded on dry land due to the low tide.

Also stranded on dry land were many octopuses.

Onyx cowrie (Cypraea onyx)
The onyx cowrie (Cypraea onyx) is very common on this shore too. The shell of this snail is very smooth and pretty, and it is usually covered by the mantle, protecting it from being scratched. The mantle also repairs and helps build the shell.

Frog shell (Bufonaria rana)
Siyang spotted this frog shell (Bufonaria rana).

Melon shell (Melo melo)
It took me a while to find this huge melon shell (Melo melo). This shell is often collect for food by fishermen, and the empty shell used to bale water. It is able to produce non-nacreous pearls valued by some collectors.

Blue dragon (Pteraeolidia ianthina)
Several nudibranchs can be found here, including the blue dragon (Pteraeolidia ianthina).

Cuthona sibogae
Agnes found this pretty Cuthona sibogae nudibranch.

Thordisa villosa
A nudibranch which I have not seen for quite a while - Thordisa villosa.

Atagema spongiosa
This huge Atagema spongiosa was about more than 10cm long.

Polybranchia orientalis
The Polybranchia orientalis is a sap-sucking slug which can be really well-camouflaged if it's among seaweed or seagrass.

Bursatella leachii
The hairy sea hare (Bursatella leachii) seemed to be in season, and we saw a number of them.

Venus clam (Marcia sp.)
Noticed that I hardly post photos of clams, so I shall end this series of photos with a Venus clam (Marcia sp.).

All in all, it was great to be back on Beting Bronok!

Friday, June 26, 2009

Changi Beach on 24 Jun 2009

It's been a while since I last visited Changi Beach, and thus, I decided to visit it with a few other RMBR Nature Guides.

Sea Apple (Pseudocolochirus violaceaus)
My favourite organism of the trip will be this Sea Apple (Pseudocolochirus axiologus),which is in fact a type of sea cucumber. You can see its tentacles extending out from its mouth, which it uses to gather edible particles in the water.

Pink sea cucumber (Cercodemas anceps)
There were several of this pink sea cucumber (Cercodemas anceps) too.

Pink thorny sea cucumber (Colochirus quadrangularis)
Looking rather similar to the previous sea cucumber will be this pink thorny sea cucumber (Colochirus quadrangularis).

Sea cucumber
This little hairy purple sea cucumber was rather abundant. Not sure of the ID though.

Holothuria notabilis
A Holothuria notabilis sea cucumber.

Pencil sea urchin (Prionocidaris sp.)
We only found one pencil sea urchin (Prionocidaris sp.).

Little black sea urchins (Temnopleurus sp.)
There were a few little black sea urchins (Temnopleurus sp.), and many of them had this worm-like organism near their mouths.

Salmacis sp.
A few Salmacis sea urchins (Salmacis sp.) were also spotted.

Luidia maculata
I found a total of 8 eight-armed Luidia sea stars (Luidia maculata).

Cake sea star (Anthenea aspera)
And this is one huge cake sea star (Anthenea aspera), which is about 20cm wide.

Biscuit sea star (Goniodiscaster scaber)
The biscuit sea star (Goniodiscaster scaber) is probably the most abundant sea star we saw during this trip.

Gymnanthenea laevis
A few orange-tipped sea stars (Gymnanthenea laevis) were also spotted.

Gymnanthenea laevis
Not all Gymnanthenea laevis come with orange tips though, like the one above, which also shows that not all of them come with 5 arms.

Sand star (Astropecten sp.)
After a while, many sand stars (Astropecten sp.) also started appearing.

Tube anemone
As the tide was really low, we found quite a few tube anemones too. This one has caught a little fish for breakfast...

Stichodactyla haddoni
Yet another stinging animal we saw will be this Haddon's carpet anemone (Stichodactyla haddoni). This particular individual was about 40cm wide.

Sea pen
We also found many sea pens among the seagrass.

Coastal horseshoe crabs (Tachypleus gigas)
I found a pair of coastal horseshoe crabs (Tachypleus gigas) trapped by a discarded fishing line.

Coastal horseshoe crabs (Tachypleus gigas)
Managed to release them eventually.

Velcro crab (Camposcia retusa)
This velcro crab (Camposcia retusa) certainly is a master of camouflage, and has stuck many little stones and shells on its exoskeleton, which is densely covered with little hooked hairs, just like velcro!

Elbow crab
This elbow crab (Family Parthenopidae) also managed to camouflage itself very well.

Spotted seahorse (Hippocampus kuda)
We found 2 spotted seahorses (Hippocampus kuda), and here's one of them.

Closely related to seahorses are these pipefishes, which blend in very nicely to the surrounding seaweed.

Geographic sea hare (Syphonata geographica)
The geographic sea hare (Syphonata geographica) appears to be in season too.

And lastly, we also saw several octopuses.

Changi is certainly one of my favourite shores, and again it did not disappoint me this trip. Will certainly visit it again when the tide is low next month :)