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First integrative trend analysis for a great ape species in Borneo

First integrative trend analysis for a great ape species in Borneo

Santika, Truly ORCID: 0000-0002-3125-9467, Ancrenaz, Marc, Wilson, Kerrie A., Spehar, Stephanie, Abram, Nicola, Banes, Graham L. ORCID: 0000-0003-4382-7684, Campbell-Smith, Gail, Curran, Lisa, d’Arcy, Laura, Delgado, Roberto A., Erman, Andi, Goossens, Benoit, Hartanto, Herlina, Houghton, Max, Husson, Simon J., Kühl, Hjalmar S., Lackman, Isabelle, Leiman, Ashley, Llano Sanchez, Karmele, Makinuddin, Niel, Marshall, Andrew J. ORCID: 0000-0002-7703-8811, Meididit, Ari, Mengersen, Kerrie, Musnanda, ., Nardiyono, ., Nurcahyo, Anton, Odom, Kisar, Panda, Adventus, Prasetyo, Didik ORCID: 0000-0001-5486-2624, Purnomo, ., Rafiastanto, Andjar, Raharjo, Slamet, Ratnasari, Dessy, Russon, Anne E., Santana, Adi H., Santoso, Eddy, Sapari, Iman, Sihite, Jamartin, Suyoko, Ahmat, Tjiu, Albertus, Utami-Atmoko, Sri Suci, van Schaik, Carel P., Voigt, Maria, Wells, Jessie, Wich, Serge A., Willems, Erik P. and Meijaard, Erik ORCID: 0000-0001-8685-3685 (2017) First integrative trend analysis for a great ape species in Borneo. Scientific Reports, 7 (1):4839. ISSN 2045-2322 (Online) (doi:

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For many threatened species the rate and drivers of population decline are difficult to assess accurately: species’ surveys are typically restricted to small geographic areas, are conducted over short time periods, and employ a wide range of survey protocols. We addressed methodological challenges for assessing change in the abundance of an endangered species. We applied novel methods for integrating field and interview survey data for the critically endangered Bornean orangutan (Pongo pygmaeus), allowing a deeper understanding of the species’ persistence through time. Our analysis revealed that Bornean orangutan populations have declined at a rate of 25% over the last 10 years. Survival rates of the species are lowest in areas with intermediate rainfall, where complex interrelations between soil fertility, agricultural productivity, and human settlement patterns influence persistence. These areas also have highest threats from human-wildlife conflict. Survival rates are further positively associated with forest extent, but are lower in areas where surrounding forest has been recently converted to industrial agriculture. Our study highlights the urgency of determining specific management interventions needed in different locations to counter the trend of decline and its associated drivers.

Item Type: Article
Additional Information: © The Author(s) 2017. Open Access. This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made. The images or other third party material in this article are included in the article’s Creative Commons license, unless indicated otherwise in a credit line to the material. If material is not included in the article’s Creative Commons license and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this license, visit
Uncontrolled Keywords: biodiversity; conservation biology; population dynamics
Subjects: S Agriculture > S Agriculture (General)
Faculty / School / Research Centre / Research Group: Faculty of Engineering & Science
Faculty of Engineering & Science > Natural Resources Institute
Faculty of Engineering & Science > Natural Resources Institute > Agriculture, Health & Environment Department
Last Modified: 25 Jun 2020 07:12

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