Monday, February 23, 2009

Robber fly - Asilidae






I've enough of dragons and damsels after shooting them for the past month; it gets boring after a while, mainly because there aren't that many species around. I keep seeing the same species all the time. This tells me that it's time for a change...

So I started hunting for robber flies. Robber flies belong to the family of Asilidae and there are over 5000 species around the world. My first encounter with robber flies happened on the very first forest outing with my close up lens and made a few macro shots of the fly. I was immediately fascinated and amazed at the details and beauty of this fly. However, after the initial encounter, I'd not seen another one for 6 months. Last week, while I was out shooting dragon flies in the forested area, I chanced upon the robber fly resting on a small twig. Wow she was a delightful subject, resting quietly on a dry twig and allowing me to photograph her from different angles. She was about 13mm long, head to tail, a real beauty, great big purple eyes, with a sharp proboscis, a hairy beard and a long abdomen. I also noticed the strong spiky legs built to grab their prey in flight.

In the next few outings, I was able to spot robber flies every time, in fact it is quite easy to spot them if you know where to look. I always remember the bible teaching " Keep asking and it will be given to you, keep searching and you will find, keep knocking and the door will be opened to you. " Mathew 7:7. On any day I can locate 3-5 robber flies at different locations within an hour. Again all of them are of the same species and measure about 8 - 15 mm long. One day while I was trying to macro focus on the fly resting on a dry twig, she disappeared from view for a microsecond and returned to the same spot immediately, but brought her dinner along. She had left the twig momentarily and grabbed a flying insect and returned to the same place.

Robber flies, also known as assassin flies, are known for their fast flight, excellent vision, and able to catch their prey in flight. They perch on low branches, logs, stones or on the ground and they rush out to catch their prey in flight, inject saliva containing toxic digestive enzyme to paralyze their prey and liquefy the insides. Once the tissues are liquefied the flies suck their prey dry, leaving the dry carcass still hanging on their proboscis. What an awesome predator- fortunately they are lone hunters, I wouldn't want to meet a nest of them, they may suck me dry.. ugh ugh.

This morning I went to the Bukit Timah Nature Reserve, a dense forested area where I used to trek and mountain bike a few years ago. While there were all kinds of insects and spiders along the track, I was specifically searching for robber flies, looking at places where they will perch, and squinting my eyes in the shadows of the foliage to look for 15mm insects resting on twigs. Within 15 minutes, I spotted my first robber fly, I was jumping with excitement because this fly was huge, it was twice the size that I had mentally envisioned, what a find ! it was the same species but only a lot larger at 30mm long. I spent some time taking the shots I needed. Ten minutes later, along the bike track I spotted another big one resting on a branch at eye level. This time she was too fast for me, she took off before I could get my gear to take a shot at her. I've found a new location for the big uns. Now to search for other species as well.

Watch out robber flies, I'm coming for you at other locations - but not the same species, please.

No comments: