The 'S' encounters at Chek Jawa

Here we go again! Another 2am wake up call this morning and off we were to Chek Jawa for an intertidal survey which we encountered many 'S's! What are these 'S's?

The first 'S' is a pleasant one and that would be the sunrise that accompanied the end of our survey. The lovely glow of the sun from the horizon over Johor and Tekong and the lush spread of seaweed with tidal pools make Chek Jawa like the Garden of Eden.

We started our survey way before sunrise when the moon is still up and shining upon the shores. We spent most of the time surveying the coral rubble as the tide was very low and we could explore the reefy areas extensively.

Ivan found one of the top 'S' finds of the day, a shark! It was first found underneath a rock. My first time seeing a live baby shark!

Here's a closer look at the shark and Dr Zeehan suggested that it looks like the bamboo shark.

Chay Hoon found the next 'S' which is scary and that would be the formidable Hollow-cheeked stonefish (Synanceia horrida)! When stepped on, the stonefish is capable of injecting toxin that would cause extreme pain. Unfortunately, these guys are too well camouflaged and hard to spot and avoid.

And of course, the next 'S' that instills fear would be the Blue-spotted fantail ray (Taeniura lymma). The stingray has serrated spines that can cut deeply and introduce venom into the wound that can cause excruciating pain. Interestingly, there was also a Fan-bellied filefish (Monacanthus chinensis) swimming across in this photo. Do we consider this as a photo-bomb? Hehe!

There were also many Seagrass filefish (Acreichthys tomentosus) that were either resting or swimming around in the tidal pools.

The coral rubble is littered with lots of 'S's aka sea stars. These are the Biscuit stars (Goniodiscaster scaber)! They are everywhere and found in various positions and sizes.

I particularly like this Biscuit star because it looks so clean with neat patterns!

It is such a joy to see many of the Knobbly sea stars (Protoreaster nodosus) on this trip as usually we would only find a a couple or a few on our previous surveys. Today I saw about 8-9.

Of about the same size, I was pleasantly surprised to find this large Cake sea star (Anthenea aspera) which is as colourful and speckled with patterns as decorated cakes that we eat.

There were also smaller Cake sea stars and they can be boring with brown colouration or pretty with pink tips.

This sea star that closely resembles the Cake sea star is known as the Spiny sea star (Gymnanthenea laevis).

We also came across two of the six-armed version of the Eight-armed sand star (Luidia maculata).

We didn't see many sea slugs or flatworms as like our previous trips. The only sea slug I found would be this Aeolid nudibranch (Cratena sp.) found on hydroids.

We seldom see the Red egg crab (Atergatis integerrimus) in the northern shores as they are more usually sighted in the southern shores as they are mainly found on reefy areas. This crab was found at a crevice of the Pore hard coral (Porites sp.).

Most of the Pore hard corals are still doing alright despite the regional bleaching event.

I only came across two colonies which are partially bleached as they are in pale yellow / brown.

Other than the Pore hard corals, we also came across this version which I'm not too sure if it is the Pore hard coral or the Sandpaper coral (Psammocora sp.).

A special hard coral found on Chek Jawa would be this Anemone coral (Goniopora sp.) that we commonly see in the south.

The Ball flowery soft corals are not as abundant here as compared to our remote northern shore at Beting Bronok.

How are the Sea fans or Gorgonians (Order Gorgonacea) doing? They are still around but definitely not as abundant as those that we find at East Coast or Changi shore.

Here are two of the different types of sea fans that we saw on the trip today. They were exposed at the lowest tide.

The disappointment of today's trip would be the loss of sponge coverage on the coral rubble. We saw a lot less sponges on this trip as compared to half a year ago. Not too sure what happened. Some of the sponges that still can be found include this black one.

All is not lost as we still do have some uncommon sponges still surviving such as these Barrel sponges (Xestospongia testudinaria).

Ivan and I came across this hermit crab that we do not know of its identity.

And both of us also stumble upon this pair of mating Mangrove horseshoe crab (Carcinoscopius rotundicauda). As part of the ritual, the males which are smaller hitch a ride on the females using their specially adapted hooked first legs.

Similar to yesterday's trip, we also came across this uncommon cowrie which is likely to be the Graceful cowrie (Purpuradusta gracilis).

The Haddon's carpet anemones (Stichodactyla haddoni) are doing very well at the southern parts of Chek Jawa! Glad that they are not bleaching.

 

I was shocked to see yet another prey of the carpet anemone as it was in the process of consuming a Biscuit sea star!

Another special find of the trip would be the Snaky sea anemone (Macrodactyla doreensis). They are named snakey anemones because of their snake-like tentacles that tend to curl. It is my first time seeing this special anemone at Chek Jawa!

We were spared the Sumatra squall though the weather forecast mentioned it will happen during predawn hours. So blessed are we to enjoy a wonderful sunrise!

Here's a look of the seagrass lagoon overlooking Johor.

May Chek Jawa remain tranquil and peaceful and continue to allow our marine creatures to thrive and for us to enjoy!

Thank you Nparks for giving us permission to document the shores of Chek Jawa as the intertidal area and the waters around it is out of bounds to the public.

Any Impact on Chek Jawa from Dec flood at Johor?

Every year towards December and January, it is likely to come across news on floods in Johor and other parts of Malaysia. It was the flood of Dec 2006 and Jan 2007 that lead to a mass mortality of marine invertebrates in Chek Jawa. To find out more on what happened back then, you may read my blog post on What caused the mass death here.

On Dec 2013, we read news of yet more flood in Johor and therefore it is imperative for us to do a check on whether the outflow of freshwater into the Johor Straits have any impact on Chek Jawa.

With special permission from National Parks Board, a small team of us were able to survey the intertidal shore of Chek Jawa on an evening. And we were relieved to not experience any sight of mass mortality on the shore.

The Haddon's carpet anemones (Stichodactyla haddoni) are still doing well. Most of them that I saw on the trip were healthy, not showing any signs of distress. I only came across one or two of them that does not look good.

I went up to the northern shore to have a look at how it is doing. The seagrasses are growing very abundantly and there were evidently more carpet anemones! A good sign. Also, there are several of these Pink warty sea cucumbers (Cercodemas anceps).

Another sign of the northern shore doing well would be having to see a wider variety of sea stars at this stretch ranging from Biscuit stars (Goniodiscaster scaber), Sand stars (Astropecten sp.) and Cake sea stars (Anthenea aspera)! What a delight to see them.

A tiny sea star was spotted by the gals and we suspect it could very well be a juvenile version of the Cake sea star.

From the quick survey, we can see that the marine invertebrates are thriving- ranging from sea cucumbers, cerianthids and sand sollars.

I came across this yellow sea cucumber that I don't think I have seen before at Chek Jawa.

The size, shape and features of this sea cucumber looks very similar to the Garlic bread sea cucumber (Holothuria scabra). It could be a different morph of the same species or yet another species altogether.

As the sun sets, we quickly checked out the coral rubble when the tide receded to its lowest. This is the richest part of Chek Jawa.

The coral rubble is very different from the sandy and seagrass habitats and is home to lots of colourful marine life such as sponges, anemones, zoanthids and ascidians.

Here's another look of the crowded coral rubble with anemones, sponges, zoanthids, fan worm and even a sea cucumber wedged amongst the encrustations.

Though the tide was not supposed to be very low, we could still see a good variety and mosaic of sponges in different colours and forms exposed. During the mass death in Jan 2007, many of these sponges literally melted due to the drastic drop in salinity.

The ladies of the survey team are superb. With them around (especially Chay Hoon), there is no lack of nudibranch and sea slug finds. One of the many finds include this Purple foot nudibranch (Atagema spongiosa).

I have not seen this Actinocyclus nudibranch (Actinocyclus sp.) since 2009 and was elated to see it at Chek Jawa. This slug is usually seen at Tuas.

Chay Hoon found a new slug sighting! And this well camouflaged slug was found through the egg ribbons laid on the sponge. This is probably a Jorunna sp.

My first time seeing this Paper bubble snail (Hydatina sp.)! This is such an elegant creature!

Here's a collage of more slugs that we saw on the trip ranging from the purplish Denison's nudibranch (Dendrodoris denisoni), Black prickly nudibranch (Atagema intecta), Hypselodoris nudibranch (Hypselodoris sp.) and the Beaded nudibranch (Hoplodoris nodulosa).

And even MORE sea stars were sighted at the coral rubble! This collage shows the Spiny sea stars (Gymnanthenea laevis), Scaly sea stars (Nepanthia belcheri), Eight-armed sand star (Luidia maculata), Biscuit star (Goniodiscaster scaber) and Cake sea stars (Anthenea aspera). 

I was searching high and low for the Knobbly sea star (Protoreaster nodosus) and was relieved to find one adult individual.

More echinoderms can be found even on the Spiky flowery soft corals (Stereonephthya sp.)! Where are they?

If you take a closer look, you would spot many of these really tiny orange brittle stars! Amazing isn't it?

Here's more commensals on soft corals. These photos show the Tiny colourful brittle stars (Ophiothela danae) that live on the Pink flowery soft corals (Family Nephtheidae).

Ending off the post, here's a feature on the flatworms at the coral rubble. Just at the foot of the pillar of the boardwalk are plenty of these Little ruby flatworms (Phrikoceros baibaiye)! There was an explosion of these flatworms and we found them in great numbers on this trip. Looks like they are in season.

There is actually another flatworm in this photo found on the pillar. Can you spot it?

Here's a closeup on the flatworm found on the pillar. This brown flatworm with white edge has not been sighted before! Probably another first sighting!

And here's a collage of the different flatworms found on the trip. They are the Blue-spotted flatworm (Pseudoceros indicus), Brown striped flatworm (Pseudobiceros gratus), Fine-lined flatworm and the Blue-lined flatworm (Pseudoceros sp.).

From this survey, it looks like Chek Jawa is doing fine and is not affected by the recent floods in the north. Let's hope the shore will continue to thrive like this blooming Delek air (Memecylon edule), an endangered tree found near the cliff of Chek Jawa.