title: Coming down from the trees: is terrestrial activity in Bornean orangutans natural or disturbance driven?
abstract: The orangutan is the world's largest arboreal mammal, and images of the red ape moving through the tropical forest canopy symbolise its typical arboreal behaviour. Records of terrestrial behaviour are scarce and often associated with habitat disturbance. We conducted a large-scale species-level analysis of ground-based camera-trapping data to evaluate the extent to which Bornean orangutans Pongo pygmaeus come down from the trees to travel terrestrially, and whether they are indeed forced to the ground primarily by anthropogenic forest disturbances. Although the degree of forest disturbance and canopy gap size influenced terrestriality, orangutans were recorded on the ground as frequently in heavily degraded habitats as in primary forests. Furthermore, all age-sex classes were recorded on the ground (flanged males more often). This suggests that terrestrial locomotion is part of the Bornean orangutan's natural behavioural repertoire to a much greater extent than previously thought, and is only modified by habitat disturbance. The capacity of orangutans to come down from the trees may increase their ability to cope with at least smaller-scale forest fragmentation, and to cross moderately open spaces in mosaic landscapes, although the extent of this versatility remains to be investigated.
authors: 1] HUTAN/Kinabatangan Orangutan Conservation Programme, PO Box 17793, 88874 Kota Kinabalu, Sabah, Malaysia [2] Sabah Wildlife Department, Wisma Muis, 88100 Kota Kinabalu, Sabah, Malaysia [3] Borneo Futures Project, People and Nature Consulting International, Ciputat, Jakarta, 15412, Indonesia [4] North England Zoological Society, Chester Zoo, Chester, UK [5].
authors: Marc
authors: M
authors: Ancrenaz
authors: 1] North Carolina State University, Department of Forestry and Environmental Resources, Turner House, Campus Box 7646, Raleigh, NC 27695, USA [2] Leibniz Institute for Zoo and Wildlife Research, Alfred-Kowalke-Straβe 17, 10315 Berlin, Germany [3].
authors: Rahel
authors: R
authors: Sollmann
authors: 1] Borneo Futures Project, People and Nature Consulting International, Ciputat, Jakarta, 15412, Indonesia [2] School for Archaeology and Anthropology, Building 014, Australian National University, Canberra, ACT 0200, Australia [3] Center for International Forestry Research, P.O. Box 0113 BOCBD, Bogor 16000, Indonesia.
authors: Erik
authors: E
authors: Meijaard
authors: Wildlife Conservation Research Unit, Department of Zoology, University of Oxford, The Recanati-Kaplan Centre, Tubney House, Abingdon Road, Tubney, Abingdon, OX13 5QL, UK.
authors: Andrew J
authors: AJ
authors: Hearn
authors: Wildlife Conservation Research Unit, Department of Zoology, University of Oxford, The Recanati-Kaplan Centre, Tubney House, Abingdon Road, Tubney, Abingdon, OX13 5QL, UK.
authors: Joanna
authors: J
authors: Ross
authors: Center for Southeast Asian Studies, Kyoto University, Kyoto, Japan.
authors: Hiromitsu
authors: H
authors: Samejima
authors: 1] School of Resource and Environmental Management, Simon Fraser University, Burnaby, British Columbia, Canada [2] Integrated Conservation, Gig Harbor, Washington.
authors: Brent
authors: B
authors: Loken
authors: 1] Wildlife Conservation Research Unit, Department of Zoology, University of Oxford, The Recanati-Kaplan Centre, Tubney House, Abingdon Road, Tubney, Abingdon, OX13 5QL, UK [2] Orangutan Tropical Peatland Project, Jl. Semeru 91, Palangka Raya 73112, Central Kalimantan, Indonesia.
authors: Susan M
authors: SM
authors: Cheyne
authors: 1] Danau Girang Field Centre, c/o Sabah Wildlife Department, Wisma Muis, 88100 Kota Kinabalu, Sabah, Malaysia [2] Organisms and Environment Division, School of Biosciences, Cardiff University, Sir Martin Evans Building, Museum Avenue, Cardiff CF10 3AX, UK.
authors: Danica J
authors: DJ
authors: Stark
authors: 1] Danau Girang Field Centre, c/o Sabah Wildlife Department, Wisma Muis, 88100 Kota Kinabalu, Sabah, Malaysia [2] Organisms and Environment Division, School of Biosciences, Cardiff University, Sir Martin Evans Building, Museum Avenue, Cardiff CF10 3AX, UK.
authors: Penny C
authors: PC
authors: Gardner
authors: 1] Sabah Wildlife Department, Wisma Muis, 88100 Kota Kinabalu, Sabah, Malaysia [2] Danau Girang Field Centre, c/o Sabah Wildlife Department, Wisma Muis, 88100 Kota Kinabalu, Sabah, Malaysia [3] Organisms and Environment Division, School of Biosciences, Cardiff University, Sir Martin Evans Building, Museum Avenue, Cardiff CF10 3AX, UK.
authors: Benoit
authors: B
authors: Goossens
authors: WWF-Malaysia, 49, Jalan SS23/15, 47400 Petaling Jaya, Selangor, Malaysia.
authors: Azlan
authors: A
authors: Mohamed
authors: Leibniz Institute for Zoo and Wildlife Research, Alfred-Kowalke-Straβe 17, 10315 Berlin, Germany.
authors: Torsten
authors: T
authors: Bohm
authors: Primate Research Institute, Kyoto University Inuyama, Aichi 484-8506, JAPAN.
authors: Ikki
authors: I
authors: Matsuda
authors: Wildlife Research Center of Kyoto University, 3rd Floor, 2-24 Tanaka-Sekiden-cho, Sakyo, Kyoto, 606-8203, Japan.
authors: Miyabi
authors: M
authors: Nakabayasi
authors: WWF-Malaysia, CPS Tower, Centre Point Complex, 88000 Kota Kinabalu, Sabah, Malaysia.
authors: Shan Khee
authors: SK
authors: Lee
authors: Unit for Primate Studies-Borneo, Institute for Tropical Biology and Conservation, Universiti Malaysia Sabah, Jalan UMS, 88400 Kota Kinabalu, Sabah, Malaysia.
authors: Henry
authors: H
authors: Bernard
authors: Biodiversity Research Centre; University of British Columbia; Vancouver, BC, Canada.
authors: Jedediah
authors: J
authors: Brodie
authors: Research Centre in Evolutionary Anthropology and Palaeoecology, School of Natural Sciences and Psychology, Liverpool John Moores University, Liverpool, UK.
authors: Serge
authors: S
authors: Wich
authors: Sumatran Orangutan Conservation Programme, PanEco/YEL, Jl. Wahid Hasyim 51/74, 20154 Medan, North Sumatra, Indonesia.
authors: Gabriella
authors: G
authors: Fredriksson
authors: Primate Research Institute, Kyoto University Inuyama, Aichi 484-8506, JAPAN.
authors: Goro
authors: G
authors: Hanya
authors: 1] Orangutan Tropical Peatland Project, Jl. Semeru 91, Palangka Raya 73112, Central Kalimantan, Indonesia [2] Department of Geography, University of Leicester, University Road, Leicester, LE1 7RH, UK.
authors: Mark E
authors: ME
authors: Harrison
authors: Primate Research Institute, Kyoto University Inuyama, Aichi 484-8506, JAPAN.
authors: Tomoko
authors: T
authors: Kanamori
authors: Leibniz Institute for Zoo and Wildlife Research, Alfred-Kowalke-Straβe 17, 10315 Berlin, Germany.
authors: Petra
authors: P
authors: Kretzschmar
authors: Wildlife Conservation Research Unit, Department of Zoology, University of Oxford, The Recanati-Kaplan Centre, Tubney House, Abingdon Road, Tubney, Abingdon, OX13 5QL, UK.
authors: David W
authors: DW
authors: Macdonald
authors: Houston Zoo, Texas, USA.
authors: Peter
authors: P
authors: Riger
authors: Anthropology Program, University of Wisconsin Oshkosh, Oshkosh, WI, 54901, USA.
authors: Stephanie
authors: S
authors: Spehar
authors: Sabah Wildlife Department, Wisma Muis, 88100 Kota Kinabalu, Sabah, Malaysia.
authors: Laurentius N
authors: LN
authors: Ambu
authors: Leibniz Institute for Zoo and Wildlife Research, Alfred-Kowalke-Straβe 17, 10315 Berlin, Germany.
authors: Andreas
authors: A
authors: Wilting
mesh_terms: D000818:Animals; D001522:Behavior, Animal; D017753:Ecosystem; D005260:Female; D008297:Male; D015233:Models, Statistical; D011148:Pongo pygmaeus / Q000502:physiology*; D014741:Video Recording