1Center for Tropical Forest Science – Forest Global Earth Observatory, Smithsonian Tropical Research Institute, PO Box 37012, Washington, DC 20012 USA
2Asian School of the Environment, Nanyang Technical University, 50 Nanyang Avenue, N2-01c-36, Singapore, 639798 Singapore
3Department of Environmental Science, Policy, and Management, University of California, Berkeley, 204 Mulford Hall, Berkeley, CA 94720 USA
4Fauna & Flora International - Indonesia Programme, PO Box 42, Sungai Penuh, Kerinci, Jambi,, 37111 Sumatra Indonesia
5San Diego Zoo Global, Institute for Conservation Research, 15600 San Pasqual Valley Road, Escondido, CA 92027-7000 USA
© The Author(s) 2018
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