Susan Cheyne

Orang-utans and gibbons compared: Implications of differences in feeding and behavioural ecology for conservation.

Hylobates albibarbis adult female by Susan Cheyne120608

Hylobates albibarbis subadult male by Susan Cheyne120608

A dramatic and unexpected 36% crash in orangutan (and probably also gibbon, though to a lesser extent) numbers occurred in Sabangau in 2001-2002, which may have been preventable through early identification of the problem (suspected to be insufficient energy intake in logging refuge areas). We aim to prevent such a catastrophe from reoccurring by collecting data on those food species most important for the species’ survival, energy balances and travel efficiency. This will enable us to implement methods and indicators to enable future monitoring of the species, and hopefully identify in advance, and therefore prevent, any future population crashes.

The ecosystem has recently achieved protected-area status (Sabangau National Park, October 2004), and locally-led enforcement and management operations are underway to counter illegal logging and restore damaged habitat. We aim to support the conservation efforts of the Indonesian organisation, CIMTROP, by continuing our research into the impacts of disturbance on the fauna and flora of the area, by:
• Monitoring trends in ape populations in different areas of disturbed forest
• Understanding behaviour and ecological needs of flagship species (orang-utans and gibbons)
• Assessing the health of remaining forest and rates of regeneration
• Identifying the number of fire hotspots reported in each area and reducing the impact of fire through supporting local fire-fighting teams
• Improving knowledge of the danger of fires both to biodiversity (habitat loss) and though smoke production (human health)
• Identifying continued threats to the forest and locations

The purpose of this is to:
• Produce ape population trend data and site specific data to be compared to other areas
• Data collected on apes through behavioural and ecological studies
• Seasonal data to show recovery and succession of forest under different conditions
• Data obtained from dept of Forestry on hotspot numbers
• Increase number of community fire-fighting teams to raise awareness and combat fires
• Survey areas of the catchment

Through long-term research into different species and habitat ecology we can help ensure the continued protected status of Sabangau and understanding this unique and complex ecosystem. Additionally, we provide jobs and training to local people and students in collaboration with Palangka Raya University.

For more information contact Susan.cheyne@zoo.ox.ac.uk or go to http://www.orangutantrop.com
http://www.indonesiangibbons.blogspot.com

You can read more about Susan's previous RSG project at http://www.ruffordsmallgrants.org/rsg/projects/susan_cheyne

Gibbon Diary June 2008 – Dave Smith, Susan Cheyne and Lindy Thompson

Dave Smith - Chun Li and Brandon Lee3 - 13_07_08

New gibbon behaviour team member
We are pleased to welcome Lindy Thompson to the Gibbon Behaviour Team. Lindy hails from South Africa and will be taking over from Dave when he returns to chilly UK at the end of July.

Ranging issues and infants
Since the dry season has begun, we have noticed that the gibbons are travelling and ranging outside their classic territorial areas. Additionally, we have noticed that Cokolat from Group C is still pregnant. She was heavily pregnant in March 2008 and it is strange that she is still so large.

After some careful searching and following of the gibbons we have now gathered more photos of infant gibbons and their mothers and we now realise that we misidentified the baby from the photo posted in May. Cokolat does not have an infant; the photo posted in May was in fact of the new Karate infant, named Brandon Lee.

Feeding ecology
Foodstuffs include less fruit and more flower and leaf material, especially as the month has drawn on, reflecting the seasonality of the forest productivity. They include: Jambu Jambu (Syzygium havilandii), Bajaka balayan (Artobotrys suaveolins), Lilin Lilin (Parartocarpus venenosus), Lunuk Buhis (Ficus spp), Tabaras flowers (Mesua spp), Katiau flowerbuds (Madhuca mottleyana), Nyatoh Gagas flowerbuds (Palaquium cochlearifolium), unripe fruit of Terantang (Campnosperma coriaceum), Mendarahan Hitam leaf shoots (Gymnacranthera farquhariania), unripe fruit of Pisang Pisang Kecil (Mezzetia umbellata), Willughbeia fruit (Willughbeia spp), Malam Malam leaf shoots (Diospyros bantamensis), Jelatong (Dyera lowii), Epiphyte, Pisang Pisang Besar flowerbuds (Mezzetia leptopoda) and Papung fruit (Sandoricum beccanarium).

27th June
Lindy and Hendri confirmed that Ninja have a new baby, named Nidji.

We are engaged in fact-finding missions with the gibbons to establish exactly which groups have infants.
Ninja and Karate are confirmed as having one infant each (Nidji and Brandon Lee respectively).
Group C does not have an infant.
Group E has possibly got a new infant but we have been unable to confirm this as they are proving very difficult to follow.

The team is continuing to investigate the ranging and infant developments and we hope to have a more detailed update by the end of July.