ACKNOWLEDGEMENTS
We would like to thank the National Parks Board and Outward Bound Singapore, and their staff at Pulau Ubin for
supporting the study and granting permission for surveys. Peter Ng supported the study and offered pertinent feedback
on the manuscript. An anonymous reviewer provided constructive comments to improve this paper. Kelvin Lim
provided valuable insight for identification of the species. We would also like to thank Andrew Tay, Celine Low, Chan
Kwok Wai, and Vilma D’Rozario, and all field assistants who were involved for volunteering their time and experti