Featured Research

from universities, journals, and other organizations

Why did the orangutan come down from the trees?

Date:
February 13, 2014
Source:
University of Leicester
Summary:
Orangutans come down from the trees and spend more time on the ground than previously realized -- but this behavior may be partly influenced by humans, a new study has found. The research is based on a large-scale analysis of orangutan terrestriality using comprehensive camera-trapping data from 16 sites across Borneo.

A young male travels on the ground in the Sabangau Forest.
Credit: © OuTrop-WildCRU (Orangutan Tropical Peatland Project/Wildlife Conservation Research Unit, University of Oxford)

Orangutans come down from the trees and spend more time on the ground than previously realised -- but this behaviour may be partly influenced by humans, a new study has found.

Dr Mark Harrison, based in the Department of Geography at the University of Leicester and Managing Director of the Orangutan Tropical Peatland Project (OuTrop) has, along with international colleagues, published results of a seven year study of Orangutans in Borneo in the journal Scientific Reports.

The research, conducted between June 2006 and March 2013, is based on a large-scale analysis of Orangutan terrestriality using comprehensive camera-trapping data from 16 sites across Borneo. In total there were 641 independent Orangutan records taken at 1,409 camera trap stations over 159,152 trap days.

The Bornean Orangutan (Pongo pygmaeus) is the world's largest arboreal (tree-dwelling) mammal. Records of terrestrial behaviour are rare and tend to be associated with habitat disturbance.

Marc Ancrenaz, from the HUTAN / Kinabatangan Orangutan Conservation Programme in Malaysia, and colleagues conducted the study. Dr Harrison, said: "We've known for some time that Orangutans use the ground to travel and search for food, but the influence of anthropogenic disturbances in driving this behaviour has been unclear. This is crucial to understand in this age of rampant forest loss and fragmentation, which is slicing up the Orangutan's jungle home.

"We found that although the degree of forest disturbance and canopy gap size influenced terrestriality, Orangutans were recorded on the ground as often in heavily degraded habitats as in primary forests.

"All age-sex classes were recorded on the ground, but flanged males -- those with distinctive cheek pads and throat pouches -- travel on the ground more. This suggests that terrestrial locomotion is a greater part of the Bornean Orangutan's natural behavioural repertoire than previously understood and is only modified by habitat disturbance."

Dr Harrison added: "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."

The authors report that more than 70% of Orangutans occur in fragmented multiple-use and human-modified forests that have lost many of their original ecological characteristics. Modified Orangutan behaviour which sees them increasingly spending time on the ground therefore has its pros and cons:

Dr Harrison explains that, "Increased terrestriality is expected to increase predation risk, interactions with and persecution by humans, and exposure to novel diseases. Unlike in Sumatra, where tigers are present, predation is less of a concern in Borneo, although infants might be at risk from bearded pigs and clouded leopards. In recent history, their biggest predator has been man, who is actually more likely to pick Orangutans off in the trees: Orangutans make a lot of noise and so are very obvious in the trees, whereas they can move with almost no noise and so more easily get away on the ground."

The scientists report that terrestrial behaviour therefore could also facilitate movement and dispersal, especially in degraded or fragmented landscapes as a result of natural or human-made processes. This could also create new opportunities to access different food sources."

Dr Harrison concludes: "Ultimately, a better understanding of what drives Orangutan terrestriality, how this influences their dispersal, movement and survival in a human-modified landscapes is important for designing effective management strategies for conservation of this endangered species in Borneo."


Story Source:

The above story is based on materials provided by University of Leicester. Note: Materials may be edited for content and length.


Journal Reference:

  1. Marc Ancrenaz, Rahel Sollmann, Erik Meijaard, Andrew J. Hearn, Joanna Ross, Hiromitsu Samejima, Brent Loken, Susan M. Cheyne, Danica J. Stark, Penny C. Gardner, Benoit Goossens, Azlan Mohamed, Torsten Bohm, Ikki Matsuda, Miyabi Nakabayasi, Shan Khee Lee, Henry Bernard, Jedediah Brodie, Serge Wich, Gabriella Fredriksson, Goro Hanya, Mark E. Harrison, Tomoko Kanamori, Petra Kretzschmar, David W. Macdonald, Peter Riger, Stephanie Spehar, Laurentius N. Ambu, Andreas Wilting. Coming down from the trees: Is terrestrial activity in Bornean orangutans natural or disturbance driven? Scientific Reports, 2014; 4 DOI: 10.1038/srep04024

Cite This Page:

University of Leicester. "Why did the orangutan come down from the trees?." ScienceDaily. ScienceDaily, 13 February 2014. <www.sciencedaily.com/releases/2014/02/140213095135.htm>.
University of Leicester. (2014, February 13). Why did the orangutan come down from the trees?. ScienceDaily. Retrieved August 21, 2014 from www.sciencedaily.com/releases/2014/02/140213095135.htm
University of Leicester. "Why did the orangutan come down from the trees?." ScienceDaily. www.sciencedaily.com/releases/2014/02/140213095135.htm (accessed August 21, 2014).

Share This




More Plants & Animals News

Thursday, August 21, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Drug Used To Treat 'Ebola's Cousin' Shows Promise

Drug Used To Treat 'Ebola's Cousin' Shows Promise

Newsy (Aug. 21, 2014) — An experimental drug used to treat Marburg virus in rhesus monkeys could give new insight into a similar treatment for Ebola. Video provided by Newsy
Powered by NewsLook.com
Terrifying City-Dwelling Spiders Are Bigger And More Fertile

Terrifying City-Dwelling Spiders Are Bigger And More Fertile

Newsy (Aug. 21, 2014) — According to a new study, spiders that live in cities are bigger, fatter and multiply faster. Video provided by Newsy
Powered by NewsLook.com
Lost Brain Cells To Blame For Sleep Problems Among Seniors

Lost Brain Cells To Blame For Sleep Problems Among Seniors

Newsy (Aug. 21, 2014) — According to a new study, elderly people might have trouble sleeping because of the loss of a certain group of neurons in the brain. Video provided by Newsy
Powered by NewsLook.com
Ramen Health Risks: The Dark Side of the Noodle

Ramen Health Risks: The Dark Side of the Noodle

AP (Aug. 21, 2014) — South Koreans eat more instant ramen noodles per capita than anywhere else in the world. But American researchers say eating too much may increase the risk of diabetes, heart disease and stroke. (Aug. 21) Video provided by AP
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
 
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:  

Breaking News:
from the past week

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:  

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile iPhone Android Web
Follow Facebook Twitter Google+
Subscribe RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins