Pangolins in global camera trap data: Implications for ecological monitoring

Citation

Khwaja H, Buchan C, Wearn OR, Bahaa-el-din L, Bantlin D, Bernard H, Bitariho R, Bohm T, Borah J, Brodie J, Chutipong W, du Preez B, Ebang-Mbele A, Edwards S & Orbell C (2019) Pangolins in global camera trap data: Implications for ecological monitoring. Global Ecology and Conservation, 20, Art. No.: e00769. https://doi.org/10.1016/j.gecco.2019.e00769

Abstract
Despite being heavily exploited, pangolins (Pholidota: Manidae) have been subject to limited research, resulting in a lack of reliable population estimates and standardised survey methods for the eight extant species. Camera trapping represents a unique opportunity for broad-scale collaborative species monitoring due to its largely non-discriminatory nature, which creates considerable volumes of data on a relatively wide range of species. This has the potential to shed light on the ecology of rare, cryptic and understudied taxa, with implications for conservation decision-making. We undertook a global analysis of available pangolin data from camera trapping studies across their range in Africa and Asia. Our aims were (1) to assess the utility of existing camera trapping efforts as a method for monitoring pangolin populations, and (2) to gain insights into the distribution and ecology of pangolins. We analysed data collated from 103 camera trap surveys undertaken across 22 countries that fell within the range of seven of the eight pangolin species, which yielded more than half a million trap nights and 888 pangolin encounters. We ran occupancy analyses on three species (Sunda pangolin Manis javanica, white-bellied pangolin Phataginus tricuspis and giant pangolin Smutsia gigantea). Detection probabilities varied with forest cover and levels of human influence for P. tricuspis, but were low ( < 0.05) for all species. Occupancy was associated with distance from rivers for M. javanica and S. gigantea, elevation for P. tricuspis and S. gigantea, forest cover for P. tricuspis and protected area status for M. javanica and P. tricuspis. We conclude that camera traps are suitable for the detection of pangolins and large-scale assessment of their distributions. However, the trapping effort required to monitor populations at any given study site using existing methods appears prohibitively high. This may change in the future should anticipated technological and methodological advances in camera trapping facilitate greater sampling efforts and/or higher probabilities of detection. In particular, targeted camera placement for pangolins is likely to make pangolin monitoring more feasible with moderate sampling efforts.

Keywords
Camera trap; Detection; Occupancy modelling; Pangolin; Macroecology; Monitoring

Notes
Additional co-authors: Emilie Fairet, Jackson L Frechette, Adrian Garside, Luke Gibson, Anthony Giordano, Govindan Veeraswami Gopi, Alys Granados, Sanjay Gubbi, Franziska Harich, Barbara Haurez, Rasmus W Havmøller, Olga Helmy, Lynne A Isbell, Kate Jenks, Riddhika Kalle, Anucha Kamjing, Daphawan Khamcha, Cisquet Kiebou-Opepa, Margaret Kinnaird, Caroline Kruger, Anne Laudisoit, Antony Lynam, Suzanne E Macdonald, John Mathai, Julia Metsio Sienne, Amelia Meier, David Mills, Jayasilan Mohd-Azlan, Yoshihiro Nakashima, Helen C Nash, Dusit Ngoprasert, An Nguyen, Tim O’Brien, David Olson, John Poulsen, Tharmalingam Ramesh, DeeAnn Reeder, Rafael Reyna, Lindsey N Rich, Johanna Rode-Margono, Francesco Rovero, Douglas Sheil, Matthew H Shirley, Ken Stratford, Niti Sukumal, Saranphat Suwanrat, Naruemon Tantipisanuh, Andrew Tilker, Tim Van Berkel, Leanne K Van der Weyde, Matthew Varney, Florian Weise, Ingrid Wiesel, Andreas Wilting, Seth T Wong, Carly Waterman, Daniel W S Challender

Journal
Global Ecology and Conservation: Volume 20

• Published version