ECOLOGY AND CONSERVATION OF MALAYAN SUN BEARS (HELARCTOS MALAYANUS) AND THEIR ROLE IN FOREST RESTORATION IN INDONESIA
Conservation status of Malayan Sun Bear
The Malayan Sun Bear (Helarctos malayanus) is the smallest bear species in the world and inhabits a range of tropical rainforests up to 2,500m throughout much of Southeast Asia, including Sumatra and Borneo in Indonesia (Fitzegerald and Krausman, 2002). It is a globally threatened species that has recently been uplisted from Data Deficient to Vulnerable by the IUCN (2008). This status change is based on a suspected >30% decline in the species over the last 30 years due to the rapid loss of habitat in Indonesia and Malaysia and hunting for exploitation of body parts (Servheen, 1999; Frediksson et al., 2008). The Malayan Sun Bear is thought to be most at risk in the Sumatran part of its range due to more extensive habitat loss, fragmentation and hunting (Augeri, 2005), while in Borneo, logging and forest fragmentation have been shown to reduce food resources, resulting in their starvation (Wong et al., 2005).
Previous research and knowledge gaps
Research to date has focused on a range of sun bear ecological aspects: biogeographic ecology (Augeri, 2005), home range and habitat use (Wong et al., 2004), feeding ecology (McConkey and Galetti, 1999), reproduction (Onuma et al., 2001; Schwanzenberger et al., 2004), and threats and conservation (Mills and Servheen, 1995; Meijaard, 1999; Frediksson, 2005). Despite this, research on the Malayan Sun Bear is considered a high conservation priority as it remains the least studied of all bear species worldwide (Servheen, 1999; Wong et al., 2004), while quantitative data on population sizes are lacking (IUCN, 2008).
Previous long-term research on Malayan sun bears has shown a preference for mature, diverse and heterogeneously structured primary forest, with habitat disturbance thought to be the most significant influence on habitat use in this species (Augeri, 2005). However, no data exist on how sun bears are adapting and utilising the increasingly degraded habitats in the threatened lowland forests of Sumatra.
Although it has been established that sun bears are potentially important seed dispersers in tropical forests (McConkey & Galetti 1999; Fredriksson et al., 2006) no research has been conducted on the role of sun bears in natural forest regeneration and how they can support forest restoration strategies. Fruit resources are thought to provide a very important opportunity for the bears to build up their fat and energy reserves (Fredriksson et al., 2006). Studies in Borneo have found over 60% of the sun bears’ food species comprised of figs (Wong et al., 2002) and during mast-fruiting events almost 100% of their diet consisted of fruit (Fredriksson et al., 2006). This will be the first study to specifically assess the role of sun bears in natural forest restoration. This will become an increasingly important area of research with the continuing loss of forest habitat in Sumatra and is essential for appropriate conservation management of this species.
In recent years human-animal conflict has become a growing concern for the conservation of some threatened species. On the island of Sumatra rapid human population growth and land use pressures have increased the likelihood of human conflict with tigers, elephants and sun bears. Local wildlife government officials now see this as a priority area for conservation action and wish to identify potential areas of conflict and then inform land use policy to minimise this problem (Didy Wurjanto, pers comm. 2009). Human-bear conflict has been documented in Borneo (Fredriksson, 2005) but no quantitative data exist for Sumatra.
Study Site
The dry lowland rainforests of Sumatra are among the most biologically diverse yet most critically threatened habitats on earth. Of an estimated 16 million hectares in 1900 only 500,000 hectares now remain. Harapan Rainforest, the largest remaining contiguous piece of this forest type, covering 101,000 hectares of intact and previously logged forest, is being actively managed for forest restoration with a view to returning the whole of the forest to its original condition. This is a foundation that has been set up specifically to implement the Harapan Rainforest initiative by the three organisations that developed this initiative – Burung Indonesia, the Royal Society for the Protection of Birds (RSPB), and BirdLife International. Harapan Rainforest maintains populations of nearly 300 species of lowland bird and over 55 mammal species, including Sumatran tigers Panthera tigris sumatrae, Asian elephants Elephas maximus sumatranus, Malayan tapirs Tapirus inidicus, Clouded leopards Neofelis nebulosa and Malayan sun bears. Research on the Malayan Sun Bear is considered a priority for Harapan Rainforest because it is likely to play an important role in seed dispersal and, hence, forest restoration at the site.
Research areas
1) Population census
Estimate Malayan Sun Bear density, population and distribution in a variety of habitat types throughout Harapan Rainforest:
- collecting sign data along line and rentice transects for abundance and occupancy surveys respectively;
- studies of nest production and decay rates along transects; and
- using camera traps to estimate occupancy and abundance.
2) Habitat characteristics and utilisation
Identifying sun bear habitat utilisation and association by:
- measuring habitat characteristics, e.g. tree species, DBH, height, distances to forest edge, and nearest road, river, human settlement, at positive sun bear habitat plots and random negative plots, which will include camera trap locations, and using logistic regression to determine which factors best explain sun bear occupancy in the different habitat types;
- identifying and classifying tree species used for different sun bear activities, e.g. rest/nest trees, food trees, and relating to this tree availability; and
- radio-telemetry/GPS satellite tagging individual bears to assess activity patterns, habitat utilisation and ranging behaviour.
3) Feeding ecology and forest restoration
Assess feeding ecology of Malayan Sun Bear:
- identify and monitor the phenology of important fruiting trees and assess the spatial and temporal availability of these fruit sources in different habitats;
- sun bear faeces will be searched for and the seeds collected. These will be planted, germinated and identified in Harapan Rainforest’s nursery. Germination success rates will be monitored;
- laboratory analysis of sun bear scats to show the frequency of food items within the sun bears’ diet; and
- data on gut passage times and defecation rates will be collected from captive sun bears at the Bornean Sun Bear Conservation Centre (BSBCC) in Sabah, and may include feeding them selected fruit types.
4) Human-Sun bear conflict
Assessing human-sun bear conflict in Sumatra by:
- interviewing local communities within and adjacent to Harapan Rainforest to assess levels of current or potential conflict;
- reports from local wildlife authorities throughout Sumatra;
- media reports on previous conflict; and
- using GIS to produce a map of current areas of conflict in Sumatra and identifying criteria to predict high risk areas.
5) Conservation management of the Malayan Sun Bear in Sumatra
This will provide strategic planning for sun bear conservation in Sumatra by:
- Modelling sun bear abundance and distribution based on survey data, habitat type, association and resource availability and highlighting potential conflict areas in mixed land-use landscapes.
- Identifying the most appropriate areas for forest protection and restoration that benefit sun bear conservation.
- Providing a tool for forest management that includes the economic costs of restoring suitable habitat for sun bear conservation and those of increasing potential human-bear conflict.
Conservation implications of this research
It is anticipated that this study will contribute greatly to our current ecological understanding of Malayan Sun Bear, filling a number of knowledge gaps, and help inform conservation actions that support the long term survival of this threatened species. It will identify the importance of sun bears as seed dispersers in fragmented, regenerating forest landscapes and how positive conservation management of the species may benefit natural forest regeneration and/or restoration activities. Key fruit trees for sun bears may form the basis for replanting strategies that benefit biodiversity and regeneration in a given habitat. This, in turn, will be linked to the economic value of conserving sun bear habitat compared to the cost of human conflict as a consequence of resource and habitat degradation and loss. This study will provide a template for integrated sun bear management and conservation in forest areas managed for restoration.
References
- Augeri, D.M. 2005. On the Biogeographic ecology of the Malayan Sun Bear. PhD Thesis. Darwin College, Cambridge, 331+15 pp.
- Fitzgerald, C.S., Krausman, P.R. 2002. Helarctos malayanus, Mamalian Species, 696: 1-5.
- Fredikkson, G. 2005. Human-sun bear conflicts in East Kalimantan, Indonesian Borneo, Ursus, 16(1): 130-137.
- Fredriksson, G. M., S. A. Wich, and Trisno. 2006. Frugivory in sun bears (Helarctos malayanus) is linked to El Niño-related fluctuations in fruiting phenology, East Kalimantan, Indonesia. Biological Journal of the Linnean Society, 89:489-508.
- Fredriksson, G., Steinmetz, R., Wong, S. & Garshelis, D.L. 2008. Helarctos malayanus, In: IUCN 2008, IUCN Red List of Threatened Species Version 2009.1, <www.iucnredlist.org>, Downloaded on 05 August 2009.
- IUCN 2008. 2008 IUCN Red List of Threatened Species. <www.iucnredlist.org> Downloaded on 05 August 2009.
- McConkey, M., and Galetti, M. 1999. Seed dispersal by the sun bear (Helarctos malayanus) in central Borneo. Journal of Tropical Ecology, 15:237-241.
- Meijaard, E. 1999. Human-imposed threats to Sun Bears in Borneo. Ursus, 11:185-192.
- Mills, J. and Servheen, C. 1995. The Asian trade in bear parts: impacts, dilemmas, and conservation perplexities. in Bears – Their Biology and Management. Proceedings of the 9th International Conference on Bear Research and Management. February 1992, Missoula MT.
- Onuma, M., Suzuki, M., Ohtaishi, N. 2001. Reproductive pattern of the sun bear (Helarctos malayanus) in Sarawak, Malaysia. J.Vet.Med.Sci., 63(3):293-297.
- Schwarzenberger, F., Fredriksson, G., Schaller, K., Kolter, L. 2004. Fecal steroid analysis for monitoring reproduction in the sun bear (Helarctos malayanus). Theriogenology, 62:1677-1692.
- Servheen. C. 1999. Sun bear conservation action plan. PP 219-222 in Servheen C., Herero, S., and Peyton, B. Compliers. Bear-Status survey and conservation action plan. IUCN. Switzerland, Gland. 309 pp.,
- Wong, S. T., C. Servheen, and L. Ambu. 2002. Food habits of Malayan sun bears in lowland tropical forest of Borneo. Ursus, 13:127-136.
- Wong, S.T, Servheen, C.W., Ambu, L. 2004. Home range, movement and activity patterns, and bedding sites of Malayan Sun bears Helarctos malayanus in the Rainforest of Borneo. Biological Conservation, 1119:169-181.
- Wong, S.T., Servheen, C., Ambu, L., Norhayati, A. 2005. Impacts of fruit production cycles on Malayan sun bears and bearded pigs in lowland tropical forest of Sabah, Malaysian Borneo. Journal of Tropical Ecology, 21:6
