Water Quality Monitoring in Bukit Timah Area: Ngee Ann Stream (18 Sep 2008)

We headed to this nice natural looking stream (affectionately termed "Ngee Ann Stream" due to its proximity to Ngee Ann Polytechnic) right after checking out Binjai Stream (see post below). But do not be mistaken about its naturalness... this stream will soon flow through a concrete tunnel before ending up in Ulu Pandan Canal.

At the first sampling point, we managed to net a big (~ 3cm length) damselfly nymph hidden in a bunch of waterside grasses and it is ALIVE! (We found a discarded exoskeleton earlier.) Regrettably, my camera is not good at capturing small objects so the pic is not posted here. However, other than the clearly irritated damselfly, no other macroinvert was netted though there were lots of hydrilla crowding one another out.

We tried our luck at bagging some macroinvertebrates at the second sampling point. No luck! We only found some gastropods (snails) firmly attached to underwater rocks. The other bug of interest is a cute looking, whitish Collembola (Springtail) inching its way across a rock surface.

It appears that our waters in Singapore are not exactly teeming with macroinverts. Do we have a problem here?

Figures (L - R): The scenic and natural open country freshwater stream that is Ngee Ann Stream; searching for bugs at the second sampling point; the naturalness giving way to stone and concrete; a surprising find - belukar (secondary forest) hidden next to the stream