My first survey of the northern shore of Chek Jawa in three years. Wow, there has been a lot of changes.
The northern sand bar seems to be moving southwards and lush seagrasses forming on its northern edge.
My last trip here was with TeamSeagrass in
Jan 2013. I was surprised to see broad seagrass meadows on the northern edge of the sand bar facing Johor! The sand bar appears to have moved southwards. Here's a video of the view.
The sand bar itself is still there but now ringed with seagrass meadows at mid tide, except at its eastern tip. Here's a video of the view.
The sandy shores are still very much alive! There were lots of signs of
Sand bubbler crabs,
Soldier crabs,
Acorn worms,
Straw tubeworms. And many prints of
shore birds.
Hermit crabs of all kinds were also common. Although we failed to find any living
Button snails here.
I only saw one
Plain sand star with broken arms, but plenty of
Cake sand dollars. Kok Sheng found two and Chay Hoon saw one
Common sand star which are no longer common on Chek Jawa since the mass deaths of 2007. The team also saw some
Biscuit sea stars and a
Painted sand star.
It's good to see common animals on Chek Jawa, such as the
Gong gong snail,
Ball moon snail,
Weasel olive snail. There were also many
Noble volutes, some laying eggs, and a
Tiger moon snail. A special mollusc found by Kok Sheng is the
Watering pot shell. Also an uprooted
Spiky sea fan. And Jonathan and Sankar found a
bunch of cephalopod eggs! These are black when the eggs are still developing and turn transparent just before the babies hatch. Kok Sheng saw a
Pygmy squid. There were many moults of small
Flower crabs. The team also saw
Stone crabs and
snapping shrimps.
In 2007, there was
mass deaths of
Haddon's carpet anemones and other animals at Chek Jawa. This is believed to be
due to heavy rainfall as marine life can't cope well with too much freshwater. There are now plenty of Haddon's carpet anemones of all colours and sizes on the seagrass meadows. None of them were bleaching although some were pale. These animals eat all kinds of other animals. I saw one with a crab in its mouth, and another with several sand dollar skeletons nearby. There were also many
Common cerianthids.
There were also many
Garlic bread sea cucumbers, some of them nestled under the carpet anemones. Other animals found near the anemones include
Ball sea cucumbers and
Solitary tubeworms. The other anemone commonly seen were
Big hermit-hitching anemones.
There were many small
Warty pink sea cucumbers, and some small
Thorny sea cucumbers. Also one
Beige sea cucumber. Sankar saw an
Orange sea cucumber.
The rest of the team spotted fishes such as the
Slender sea moth,
Kite butterflyfish and
Shadow goby. They also saw a
Mangrove horseshoe crab.
The seagrasses are growing lush at the northern edge as well as in the middle of the Chek Jawa lagoon.
Spoon seagrass covered large areas, as well as
Needle seagrass. I also saw some
Fern seagrass. The sand bar near the pontoon has moved westward towards the boardwalk and is surrounded by lush seagrass meadows including lots of
Smooth ribbon seagrasses. But I couldn't find any
Beccari's seagrass in the north or in the middle near the boardwalk pontoon.
Much of the seagrasses in both the northern edge and middle of the lagoon were covered with black scummy growths. Cyanobacteria?
A closer look at the black scummy growths. Kok Sheng saw what seems like dugong feeding trails.
Mangroves fringe the route to the northern shoreline of Chek Jawa. The trees were doing well, although some were being buried in sand.
At the same time, there is a great deal of erosion on other parts of the shore with trees falling over both towards the sea and towards the land. Under this tree, at the red arrow is what looks like a tiny shrub of the very rare Critically Endangered
Mentigi (
Pemphis acidula).
Here's the bush under the fallen tree.
A closer look at the bush. It wasn't flowering or fruiting. The last time we saw a Mentigi bush here was in
Jan 2011. It was a much bigger bush and might be a different one from this.
On the rocky shore near the boardwalk, the Critically Endangered
Delek air (Memecylon edule) is fruiting.
I had a closer look at the area where the
Security Barrier aka fence around the northern shore of Pulau Ubin starts.
Right at the fence, there was a big pile of trash that looks like they were dumped there. Because I know barbed wire doesn't float.
There is also a lot of other trash on the high shore that looks like they might have floated over.
On the tip of the northern sand bar facing the Johor River, there was hardly any trash washing up. Only natural flotsam of mangrove leaves, fruits and flowers.
The water in the Johor Strait looked alright. Usually, if the churn looks like teh-o then there is probably a plankton bloom going on.
We were treated to a beautiful sunset as we headed home.
Thanks to NParks for permission to survey this shore and keep tabs on how it is doing.
Photos by others on this survey
