Dr Dan is in town and we can't wait to visit Chek Jawa together on a cooling Sunday morning. Other than Siva and company, Dr Dan also brought along his wife too and everyone was very excited. (Photo by Ria)
Though the tide wasn't spectacular, it was good enough for us to learn so much from this trip. Dr Dan is an expert of the shores and we take this golden opportunity to learn from him.
From this photo you can see the exposed part that it is actually the opportunistic colonization of these mussel beds. It is seen as a thick 'carpet' of tiny mussels that trap a soft bed of silt by creating a communal nest of byssus threads. These mussels are probably Musculista sp. which incorporate sediments, bits of broken shells and other debris into the mussel nest. The nest is pockmarked with little slits, each housing one mussel.
Dr Dan was very excited to know that these were not seen in Chek Jawa before and he speculates that the common seastars might eat them. Siti once shared that their presence is due to freshwater influx, which I kind of doubt. Are they cyanobacteria too?? Have to really learn more about them yeah. (Photo by Ria)
What eats these mussel beds? We have to find out how transitional are these patches and will the recovery of common sea stars cause the future disappearance of these mounds? Watch out for it.
We headed towards the northern sandbar towards where the button shells are. If you slightly remove the top surface of the fine sand, you will be amazed to see these jewels of Chek Jawa! These snails are actually preyed upon by moon snails.
Dr Dan was excited, as heard from this video, that these button shells are back (or they might all along be there). Take a look at this video as Ria, Siva and Dr Dan shares the interesting facts of these button shells and how they disperse when disturbed.
I did not take many photos because was busy at work. For more information of the trip, please take a look at wildfilm's account by Ria.
We were looking out for the top 5 charismatic macrofauna to monitor. They are..drum rolls..
1. Carpet Anemone (Stichodactyla haddoni)
2. Peacock Anemone (Order Ceriantharia)
3. Button Shells (Umbonium vestiarum)
4. Mounds of mussel beds (probably Musculista sp.)
5. Cake Sand Dollar (Arachnoides placenta)
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6. Common Seastar (Archaster typicus)- Watching out for their comeback!
For the next field trip, we will be monitoring a maximum of 25 Haddon's carpet anemones and to study their growth (through tentacle density) and locomotion over time.
Towards the end of the shore trip, Ria found this interesting polychaete.
We proceeded for a quick boardwalk with Dr Dan and chanced upon these overly-enthusiastic visitors climbing down to the sandbar though they are not allowed to. And it is also a dangerous act for both the visitor and the animals. For the visitor because the tide can come in faster than you can imagine and you will be trapped.
Dangerous for the animal because as curious beings, we may tend to disturb the precious lifeforms of CJ. Look at how they use a stick and poke at most probably a carpet aneomne. Seriously I hope they can leave the anemone guys alone and allow them to recover.
It was an interesting first half of the morning. As we bidded farewell to Dr Dan and gang, Ria and I headed towards the mangrove boardwalk to join for the recce of Naked Hermit crabs.
Wow, another banded krait was spotted!! These snakes are very venomous, far worse than cobra.
Further towards the house no. 1 side on the coastal boardwalk, Ria introduced this portion where a landslide had occured before. Good for geography lessons.
The pong pong trees along the streets were once imported but this one here is native.
I always like to find the seashore nutmeg tree that is already rare in Singapore.
Towards the end of a 5 hour field trip, the finale was this spider with a net of orange mass.
If you look closer, they are babies!!
This hut outside CJ is so lively and it is really a wonderful end of the series of low tides last week. It's heartening to see many people coming to appreciate the beauty of nature.
Thanks Ria for the wonderful lunch you treated to the NHC people and also the urgent ride to my tuition afterward.
Thanks Siva, Dr Dan and company for coming and sharing much with us.
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