Sunday, March 15, 2009

Sarawak: Dragonflies at Kubah

I have recently begun to notice dragonflies. I always knew that they were there, of course, but failed to appreciate not only diverse they were, but what wonderful subjects they made for a nature watcher and camera bug (other types of bugs, of course, should avoid these predatory beasts at all costs). For one thing, they are varied, beautiful and (to some extent) identifiable in the field. For another, dragonflies tend to hold still when they perch. If you flush them off, they will, as likely as not, head back to exactly the same perch in a few seconds. This makes them wonderful subjects for impatient and clumsy photographers -- even better than butterflies or birds.

With that in mind, I spent a fair bit of time during my recent trip to Kubah National Park near Kuching stalking the local Odonata (the fancy term for dragonflies and their relatives). I managed to photograph five different species in the widespread family Libellulidae, often known as Skimmers. (There is, by the way, an excellent book on the dragonflies of Borneo, but my copy is sitting at home in Canada doing me very little good. The following identifications are based on photos at the Asia Dragonfly website, and could easily be wrong!)

Three of them, not really forest species, hung around an open patch of boggy grass at the head of the Rayu Trail:
This one is a male Orthetrum glaucum. The name glaucum refers to his powdery-blue (or glaucous) abdomen. Dragonflies with this sort of waxy, powdery coating (and there are lots of them, worldwide) are called pruinose, and the powdery condition itself is called, of course, pruinosity (or, if you prefer, pruinescence). It usually appears on older males, and may be a signal that the insects are ready to mate (though it may also reflect excess sunlight, useful for dragonflies that spend a lot of time sitting in the open).

This is, I believe, another Orthetrum, but there are a number of dragonflies with fat red abdomens in Borneo so I could be wrong. I will put it down as Orthetrum chrysis, and await developments.

Finally, this is one of the grasshawks (Neurothemis), probably a young animal as the adult males turn deep bronzy-red. Grasshawks are hard to identify, the most obvious differences apparently being the shape of the clear (or hyaline) areas at the tips of the wings, and after poring over photographs of several different species I have to admit that I am not sure which one this is.

Not far from the trailhead is the Frog Pond, a shaded forest pool apparently created and maintained by generations of wallowing bearded pigs. At night, of course, it is great for frogs, and by day it is visited by the Oriental Dwarf Kingfisher, a glowing little bird that looks as though it had been lit up from the inside. David Bakewell's blog has terrific pictures under his March 4-7 entry. As for dragonflies, I noticed two or three species but could only photograph this one:
It is, I think, Tyriobapta torrida. We would call this a "saddlebags" in North America, because the black patches on the wings make the dragonfly look as though it is carrying luggage!

The most spectacular of the lot, though, was this brilliantly iridescent Cratilla metallica -- how many dragonflies have golden eyes? -- and this one came to us. It decided that David's car antenna was the ideal dragonfly perch, and kept returning to it (even though this photo was taken on a nearby twig). Now that's a cooperative subject!

3 comments:

  1. Looks like you have got all of them correct. The red wing dragonfly is Neurothemis terminata. The red abdomen one most likely is a Orthetrum chrysis.

    Cheers,
    Ian
    http://odonata-malaysia.blogspot.com/

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  2. Excellent narrative Ron. Look forward to seeing more!

    Dave

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  3. Wonderful, pure magic, congrats. Mari

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