NSS Kids’ Fun with Night Creatures at Bukit Batok Nature Park

Text & Photos by Gloria Seow, Education Committee Vice Chairperson

Thanks to some publicity from The Straits Times, our night jaunt at Bukit Batok Nature Park on 23 June 2018 was nearly twice oversubscribed. To manage the numbers, we split into two groups with Auntie Gloria, Auntie Lena and Uncle Timothy leading the first group, while Uncle Hang Chong and Auntie Cuifen shepherded the second.

Our first Colugo was seen licking the tree bark occasionally.

At twilight, this patch of woods comes alive with nocturnal animals emerging to forage. Accompanied by a cricket chorus, we trooped inwards from the car park whereupon we encountered insectivorous bats hunting along the forest corridor, as well as fruit bats feasting on figs and other ripe goodies. Just outside the main toilets, Auntie Gloria spotted the first enigmatic Sunda Colugo (Galeopterus variegatus) up a tree on a fairly low branch. This caused a flurry of excitement amongst parents and kids alike as it was a lifer for many. The Colugo stayed in one spot licking the tree bark occasionally, probably feeding on lichen. Uncle Hang Chong’s group came by later and enjoyed the sighting too. Between us, we found four Colugos that night. To some, our second Colugo looked like a giant brown leaf from afar, given that it was hanging under a large branch at least five stories above us. Examining our photos later, we realised that there was in fact a baby ensconced within its mama’s patagium – the loose flap of skin connecting the four limbs and tail that aids the Colugo in ‘flying’ from tree to tree. Our third Colugo was spooked by our torches and provided some action as it scaled a bare trunk in mere seconds. The fourth Colugo was spotted by Uncle Hang Chong inside the forest about 10 m from the concrete path.

A well-camouflaged Asian Swamp Eel.

At a shallow stream near the quarry, Uncle Hang Chong found an Asian Swamp Eel (Monopterus javanensis) which vanished by the time our group came by. Luckily, Auntie Gloria noticed another eel just a couple of metres away, partially hidden under a sunken leaf. This eel was less shy, providing us full views of its narrow head, tiny eyes and sinuous snake-like body. It then wedged itself between a rock and the muddy substrate, hoping that its dull coloration would serve to camouflage it. We took some photos and left it in peace.

We then threaded our way to the other side of the park, seeking out the streams there. As we stood over a small bridge, we found a number of Whitespots (Aplocheilus panchax) floating placidly. This is a small silvery fish that resembles the guppy, making it a popular aquarium pet. It can be identified by a prominent white spot at the top of its head and a dark spot on its dorsal fin. As the only killifish native to Singapore, it grows up to 6 cm long. Auntie Lena said that it is also called the ‘mosquito fish’ as it feeds on mosquito larvae. Our patience paid off as Auntie Gloria found another target species lurking in the same waters – the Common Walking Catfish (Clarias batrachus). Two of these nervous fast-moving catfishes were highly sensitive to our torches. Each time we trained our lights on it, they would duck behind something or burrow into the soft mud. When we focused our beams elsewhere, they would reveal themselves. In the semi-darkness, we could just make out their reddish-brown heads contrasting with their grey bodies. Who could mistake those ‘whiskers’ (ie. barbels) that give the fish its name?

Satisfied, we moved further upstream where Auntie Gloria again located what we sought – the Lowland Freshwater Crab (Parathelphusa maculata) – one of four freshwater crab species native to Singapore. This crab can be found in other parts of Southeast Asia whereas the other three freshwater brethren are endemic. Thankfully, our pair of crabs did not mind being in the spotlight, continuing to feed unperturbed. While observing them, a sharp-eyed participant noticed a large Common Walking Catfish that had been lying motionless near the crabs the entire time, somewhat covered in mud.

The Lowland Freshwater Crab is one of four freshwater crab species native to Singapore.

While wishing for some frogs to complete our trip list, we suddenly came across two species sitting within metres of each other on a grassy patch. Our Crab-eating Frog (Fejervarya cancrivora) appeared to have a cataract in one eye, while our Asian Toad (Duttaphrynus melanostictus) became over-friendly, hopping up a participant’s shoe in its enthusiasm. Uncle Hang Chong’s group reported seeing a snake moult high up on the underside of the roof of an outdoor pavilion. Apparently, these pavilions are favourite spots for snakes to shed their old skin as they provide something to rub against.

What a bounty of sightings in just two hours!

An over-friendly Asian Toad.