Pasir Ris Mangrove

Today, I met up with XF, his wife and his daughter for a walk at Pasir Ris mangrove. It started raining when we were in the cab, but fortunately stopped when we reached Pasir Ris.


After a quick look at the herbal garden, we headed for the mangrove boardwalk. Perhaps due to XF's beginner's luck, we managed to see quite a few interesting stuff.


The top find of the day must be this - a small population of Thespesia firebugs (Dysdercus simon) on a portia tree (Thespesia populnea)! It was initially thought that this bug could only be found in our mangrove in the western part, until we found a population on Pulau Ubin last December.


Not too far away from the portia tree was a sea hibiscus tree (Talipariti tiliaceum), and there was a huge population of cotton stainer bugs (Dysdercus decussatus) living on it. Unlike the less common Thespesia firebug, the cotton stainer bug has a red head instead of a black one.


There were lots of tree-climbing crabs (Episesarma spp.) on the trees, since the tide was still high. These crabs climbed up trees to escape from predatory fishes during high tide. The above crab has purple claws with white tips, so it's probably a violet tree-climbing crab (Episesarma versicolor).


Tree-climbing crabs are also called vinegar crabs, since they are sometimes pickled in vinegar by the Teochews, who will then eat them with porridge. The above crab with red claws should be the Singapore tree-climbing crab (Episesarma singaporense).


The giant mudskipper (Periophthalmodon schlosseri) at Pasir Ris were really huge. They are the biggest mudskippers in Singapore, and can be really fierce hunters of smaller animals.


And this is one of the mudskipper's prey. I initially thought that it was an eel, since it was rather long (about 50cm) and was swimming too quickly for me to see carefully.


However, when it was chomped into 2 halves by the mudskipper, the second half started wriggling on the spot, and I could see that it was a segmented worm (Class Polychaeta)! This was quickly eaten by the mudskipper.


After observing the several segmented worms swimming by and got chomped up, XF spotted a real eel! it was really huge, at least a metre long. And things got really exciting when it managed to set its teeth on a tree-climbing crab!


It was twisting and turning. Not sure if it was trying to hit the crab against the substrate to kill it.


Apart from the mangrove fauna, the plants were out to impress too, with many of the sea derris (Derris trifoliata) in full bloom!


Several of the bakau putih (Bruguiera cylindrica) had developing their seedlings, which were attached to the parent plant. This is one of the most common mangrove plant in Singapore.


This fat cigar-like seedling belongs to the tumu (Bruguiera gymnorhiza).


This mangrove tree, Ceriops zippeliana, was only recorded in Singapore a few years ago.


The mature propagules of the bakau minyak (Rhizophora apiculata) has a red collar. This plant is commonly planted in plantations to be harvested to make charcoal.


The bakau kurap has broader leaves and bigger propagules up to 70cm long.


The nipah palm (Nypa fruticans) is where you get your attap chee for your ice kacang. Several of them can be found by the sides of the boardwalk. The fruit is basically a cluster of seeds, and every seed will have one attap chee inside.


The Nyireh batu (Xylocarpus moluccensis) is rather commonly seen here compared to the other mangroves of Singapore. Unfortunately, all the trees I saw were not fruiting.


Apparently, Nparks have planted several rare plants here too, including the Rapanea porteriana above. This plant was once commonly found in the mangroves and coastal forests of Singapore, but is now seldom seen due to coastal development which destroyed most of its habitat.

This has been a nice little trip with quite a few surprise finds. Hopefully XF and family had enjoyed the trip :P