Marc Dragiewicz, one of our long-term research collaborators, talks about his favourite sound of the forest; the song of the mangrove whistler.
One of my favourite things in the world is walking into a forest where I had never been before. One thing I love about forests are the sounds. I was very excited to step into Sabangau for the first time, but before I could disappear beneath the canopy the forest came to me in the sound of a whistler.
This call really grabbed me and reminded me I was somewhere exotic. They make a series of pure melodic whistles before letting out an explosive final note or two (you can listen to the call below). I didn’t know what it was at that point, but I was excited to find out. That was a memorable day. I entered the grid, saw a hand full of birds I had never seen before, but failed to find the maker of one of the most prominent sounds in the forest.
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Mangrove whistler. Photo by Jerry Oldenettel/Flickr |
Days later I was stopped on a trail when something caught my eye and I found a little drab, grey bird in my binoculars. I thought it was a flycatcher because of its upright posture and overall appearance, but when I looked it up I learned it was a mangrove whistler. By reading the description of the call I realised that it was the bird I previously heard. Over the next few years I had many interesting encounters with this bird.
In my first weeks of bird surveys in Sabangau I realized that the whistler was often flushed from active swarms of army ants or “fire ants”. Curious about this relationship, I sat with an ant swarm for only a few minutes before I saw the whistler return. Strategically perched over the swarm, the whistler periodically caught a fleeing insect. I had accidentally discovered the first example of “ant following” which has been thoroughly described in the Neotropics and Africa, but not anywhere in Asia. Upon further examination, I learned that the swarming ant so common in Sabangau is a species yet to be described to science. So we learned a lot from one of the least interesting-looking birds of Borneo!
Years after my wonderful time in the Sabangau Forest, through the slow march of science and the efforts of fellow OuTrop nature-lovers, we had two papers published on the whistler at the end of the year. I would like to thank all OuTrop volunteers for helping keep the effort going and encourage anyone interested in a hands-on conservation learning experience to come to Sabangau. I guarantee the experience will be rewarding and that the things you learn and people you will meet will prove beneficial to your future in the conservation world.
Mini-bio
Marc Dragiewicz started the OuTrop bird monitoring programme in 2005 and returned to carry out research on four occasions over the next five years; assisting with off-site surveys as well as in the Sabangau Forest. He has worked, lived, travelled, and studied in forests all around the equator.
He is now making forest conservation documentaries with his production organisation eyesoftheworldfilms.com. You can follow Eyes of the World Films on Facebook.