Studying Frog Calls in Sarawak Totally Protected Areas

Kalophrynus heterochirus, the Variable Sticky Frog,
is making calls to lure the female, which is not far away.

I spent a week at Kubah National Park last month, recording frog calls and figuring out which species were calling during the dry season. The Frog Pond was almost completely dried up, with only a small pool left in the centre. Even so, we still managed to record some great frog calls, especially when the weather turned cloudy with a bit of rain or after a heavy afternoon downpour.

This was my first time recording frog calls, and honestly, it was much more complicated than I expected. Whether I got a recording really depended on the frog. Some frogs are extremely shy or simply don’t like people. These ones drove me crazy because as soon as I got close, they would go silent until I left. Others didn’t care at all that I was there. They just kept singing until a female showed up, and then, once their job was done, they hopped off together.

I used a portable recorder consisting of the Zoom F3 Field Recorder and the Sennheiser MKE 600 microphone. My ornithologist friend, Dr. Alison Styring, suggested this setup. Back in 2006-2007, I joined her for a dawn chorus recording using a Marantz recorder, but that model is no longer available in Malaysia. Honestly, I don’t have much experience with audio recording, and I’m still new to studying frog calls.

Ten species of frog and toad calls were recorded out of 18 species that were observed in different trails, streams and ponds that we surveyed. These ten species are the ones that are actively making calls during the duration of our trip. It is known that frogs produce calls for mating purposes, and only males are active in making these calls. Some species are very shy and secretive, which makes it challenging to locate them while making calls. Of course, they are also very good at camouflage and hide well in silence.  

We wrapped up our trip after six nights of surveys. I wasn’t completely satisfied because on the last night, I had trouble with the recorder connector. I felt relieved when I checked and saw that I still managed to record the call of the Tree Hole Narrow-mouthed Frog, even if it wasn’t the best version I had hoped for.

Taking this opportunity to thank Prof. Dr Indraniel Das from IBEC, UNIMAS and his PhD student, Izneil, for teaching us the standard protocols for frog bioacoustic study. As well as my team members, Akas Bit and Broddy Mien, Kubah NP and Matang WC staff for making this fieldwork possible. Thanks so much, team!

All the photos were taken with a Huawei Mate 10 Pro. It’s not a high-end mobile phone, but it does the job well enough.