Nightlife at Tanjong Rimau! Crabs, shrimps and octopuses

My first leisure intertidal walk + night walk! Tanjong Rimau is a natural rocky shore (has a bit of sandy shore as well) in Sentosa, and has two entry points, one behind Underwater World Singapore (UWS) and the other behind Rasa Sentosa Resort.

We entered from the UWS side, where there was a small area of sandy shore. Being dark, and not equipped with a decent camera, I don’t have many decent photos. Looking through my photos on laptop, most of the time I couldn’t even tell what I was taking Will process my photos later and maybe upload here another time.

But anyway the shores were alive, even at night! Or perhaps, especially because it was at night. I once wondered, were marine animals tide-dependent or light-dependent? For terrestrial animals, they can be classified as diurnal (active in the day like us humans. Most of us anyway.), crepuscular (active at dusk and dawn) or nocturnal (active at night). But for marine animals, especially those living in the intertidal zone, I thought perhaps they might be tide dependent, like active at low tide/high tide. After yesterday (3 Sept) though, I think they’re probably light-dependent, and tide is a secondary consideration. I think only, not sure.

Because there were crabs EVERYWHERE! Crabs of all kinds. Usually, even on a low tide (which is when I explore the shore), you have to flip rocks to find crabs. But at night, the crabs scuttle to get out of the spotlight. Swimming crabs, purple climber crabs, moon crabs, a hairy crab, red-eyed stone crabs and more that I can’t identify. Most were feeding on algae or just slacking around maybe.

Apart from crabs, shrimps were also having their fun night out. Snapping shrimps and glass shrimps mostly. At first you don’t see any, but when you stop and focus on a spot (the headlamp/torchlight shining on a particular area helps a lot in focusing), you realise there are loads of shrimps there. Even if you can’t see the shrimp itself, you can definitely see the eye shine.

While walking towards the Rasa Sentosa exit point, Chay Hoon spotted a baby Stonefish! A small and rather ugly thing, about maybe 8cm long? Looking really nondescript, I’m thankful that Chay Hoon spotted it, else I might just have stepped on it

Nearer the rock pools, I started looking out for octopuses. I’ve always really wanted to see octopuses. I saw a couple on Pulau Semakau, but I think that was probably about it. They haven’t yet lost their appeal to me, mainly because most of them are nocturnal, and I usually go on walks in daylight. And I saw a few! Some really small ones, about palm-sized maybe? Not including tentacle length. And one big one. And that about made my trip, I don’t have very high expectations (:

Chay Hoon also showed us a Sea grape slug, this tiny little green thing (about 1cm?) that looked like sea grapes but was actually a slug. It eats sea grapes (a kind of seaweed). Marcus Ng also found a special Ghost crab, not commonly seen:)

By the time we left, it was close to 11pm. It was a nice break for me though, glad for the evening tides because it means I can probably go out more!

 

For other posts on this trip with awesome photos:

Ria’s Wild shores of Singapore