Saturday, 28 April 2012

White-barred Duskhawk in Bishan Park

Among the few species of dragonflies seen along the stream of Bishan Park, White-barred Duskhawk (Tholymis tillarga) is the only one which is active during late afternoon. In the morning and earlier afternoon, they hide in shady places, perching motionlessly under leaves, twigs and grass, and are hard to spot.

They are most active at around 6 pm. The males are constantly patrolling up and down the stream, and are sometimes engaged in brief but vigorous territorial fights. Many of them, especially the older males, have damaged wings as a result of these fights.

The male featured in the footage below has a clipped right hindwing. Whether this has affected his flight performance is not apparent. What is obvious is that he can still guard his territory, capture and mate with a female and protect her from harassment by other males while she is ovipositing (laying eggs). I believe this male will have his next generation thriving in Bishan stream.

Most of this footage was taken at 120 fps and 240 fps. Only 3 seconds of it (01:12 to 01:15) was taken at normal speed (30 fps). Please choose 480p video quality to view.

Thursday, 19 April 2012

Bright side of Bishan Park

Please watch this movie in HD (1080p) quality.

This is the newly created stream in Bishan Park, which is supposed to have plants integrated into its banks to encourage the development of natural biodiversity, according to NParks ( Well, frequent and thorough clearing of vegetation observed does not suggest this. At least for dragonflies, the stream has only attracted a few common species (e.g. Crocothemis servilia, which can tolerate disturbed habitats). Even the very common Neurothemis fluctuans are difficult to find along Bishan stream.

Nevertheless, after two months of patience and hard work, I managed to put together a movie showing the brighter side of Bishan Park. From 1:16 onwards, it appears that the stream is teeming with dragonflies. Actually, those are only two species, Crocothemis servilia and Tholymis tillarga, and the video was taken when the vegetation (mainly grass) had grown back to a certain height. A few days after this clip was taken, the team of grass cutters came and cleared all the vegetation.

I really hope to see more variety of plants growing along the stream. I also hope to see meadows on the slopes. There are simply too many lawns all over Singapore. Lawns are expensive and noisy to maintain and they are useless bio-systems. Meadows attract wildlife. Just imagine the different plants, flowers and the different insects that come to visit these flowers.