Batang Ai-Lanjak-Entimau (BALE) landscape

Asia > Malaysia > Batang Ai-Lanjak-Entimau (BALE) landscape

Summary

• Northwest Bornean orangutans (Pongo pygmaeus pygmaeus) are present in Batang Ai-Lanjak-Entimau (BALE) Landscape.
• It has been estimated that 355 (CI: 135-602) individuals occur in the site.
• The orangutan population trend is decreasing.
• The site has a total size of 1,894 km².
• Key threats to orangutans are forest loss, habitat degradation and hunting.
• Conservation activities have focused on education and awareness raising programs implemented by the WCS.
• The site is home to the largest population of orangutans in Sarawak, Malaysia.

Site characteristics

The Batang Ai-Lanjak-Entimau (BALE) landscape consists of two contiguous protected areas: the Batang Ai National Park and the Lanjak-Entimau Wildlife Sanctuary. The "Greater BALE landscape" includes areas surrounding BALE (Pandong et al. 2018). The BALE landscape contains the largest population of orangutans in Sarawak, Malaysia (Tisen & Silang 2016). Together with the Betung Kerihun National Park in Indonesia, the three protected areas (Betung Keihun, Batang Ai, and Lanjak-Entimau) form a transboundary biodiversity conservation area (WCS n.d.).

Table 1. Basic site information for Batang Ai-Lanjak-Entimau (BALE) landscape

Area	1,894 km²
Coordinates	1.314962 N, 112.097504 E
Designation	Protected Landscape
Habitat types	Subtropical/tropical moist lowland forest, water storage areas [over 8 ha]

IUCN habitat categories Site designations

Ape status

The Batang Ai-Lanjak-Entimau (BALE) landscape consists of two contiguous protected areas: the Batang Ai National Park and the Lanjak-Entimau Wildlife Sanctuary. The "Greater BALE landscape" includes areas surrounding BALE (Pandong et al. 2018). The BALE landscape contains the largest population of orangutans in Sarawak, Malaysia (Tisen & Silang 2016). Together with the Betung Kerihun National Park in Indonesia, the three protected areas (Betung Keihun, Batang Ai, and Lanjak-Entimau) form an important transboundary biodiversity conservation area (WCS n.d.).

Table 2. Ape population estimates in Batang Ai-Lanjak-Entimau (BALE) landscape

Species	Year	Abundance estimate (95% CI)	Density estimate [ind./ km²] (95% CI)	Encounter rate (nests/km)	Area	Method	Source	Comments	A.P.E.S. database ID
Pongo pygmaeus pygmaeus	2001		0.7		BALE landscape	Line transects (Distance)	Gurmaya & Silang 2002
Pongo pygmaeus pygmaeus	2004	1,143–1,761			BALE landscape	Line transects (Distance)	Wich et al. 2008
Pongo pygmaeus pygmaeus	2011-2015	355 (135-602)	0.5249 ( 0.1964-0.8842)		Greater BALE landscape	Marked nest count method	Pandong et al. 2018	The Greater BALE landscape includes areas surrounding BALE.

Threats

Forest loss, habitat degradation, and illegal hunting represent the main threats to orangutans at the site (BirdLife International 2021, WCS n.d.). Local communities living around the BALE landscape do not traditionally hunt orangutans, as the Ibans believed that their ancestors were reincarnated as orangutans (Pandong 2019). However, this cultural protection is on decline, as carcasses of orangutans have been found in the area with clear signs of killing (Pandong 2019).

Table 3. Threats to apes in Batang Ai-Lanjak-Entimau (BALE) landscape

Category	Specific threats	Threat level	Quantified severity	Description	Year of threat
1. Residential & commercial development		Unknown
2. Agriculture & aquaculture	2.1 Annual & perennial non-timber crops	Present, but threat severity unknown		Conversion of land into oil palm plantations (Pandong 2019).	Ongoing (2019)
	2.2 Wood & pulp plantations	Present, but threat severity unknown		Industrial forest plantation has increased in Sarawak for over three decades with acacia (Acacia mangium) as the preferred species, as it is fast-growing and able to grow on poor and degraded soils (Pandong 2019).	Ongoing (2019)
3. Energy production & mining		Unknown
4. Transportation & service corridors	4.1 Roads & railroads	Present, but threat severity unknown		Logging roads that facilitate hunting activities (Pandong 2019).	Ongoing (2019)
5. Biological resource use	5.1 Hunting & collecting terrestrial animals	Present, but threat severity unknown		The cultural taboo against hunting orangutans and the respect for the total ban of hunting (Pandong 2019).	Ongoing (2019)
6. Human intrusion & disturbance		Unknown
7. Natural system modifications		Unknown
8. Invasive & other problematic species, genes, diseases		Unknown
9. Pollution		Unknown
10. Geological Events		Absent
11. Climate change & severe weather		Unknown
12. Other options		Absent

IUCN Threats list

Conservation activities

Three more national parks have been gazetted outside the BALE landscape: Ulu Sebuyau National Park (July 2010), Sedilu National Park (September 2010) and Sabal National Park (August 2018). Wildlife Conservation Society (WCS) have been active in the implementation of conservation interventions. Their activities have focused on education and awareness raising, as well as conducting orangutan surveys and rapid assessments, co-creating a Strategic Action Plan for orangutans, and developing a radio programme in the Iban language (WCS n.d.).

Table 4. Conservation activities in Batang Ai-Lanjak-Entimau (BALE) landscape

Category	Specific activity	Description	Year of activity
1. Residential & commercial development	Not reported
2. Agriculture & aquaculture	Not reported
3. Energy production & mining	Not reported
4. Transportation & service corridors	Not reported
5. Biological resource use	Not reported
6. Human intrusion & disturbance	Not reported
7. Natural system modifications	Not reported
8. Invasive & other problematic species, genes, diseases	Not reported
9. Pollution	Not reported
10. Education & Awareness	10.4. Regularly play TV & radio announcements to raise primate conservation awareness	To engage the local communities, the orangutan radio program entitled “Jerita Bujang Sigat” or “The Saga of Bujang Sigat” was developed and aired. The goal of the program was to engage local communities to conserve orangutans and other wildlife in the BALE landscape (WCS n.d.).	2011-2012, 2018
	10.6. Integrate religion/local taboos into conservation education	A collection of local folklores, stories, taboos and tales about orangutans exist around the BALE landscape have now been documented (they existed as oral stories before). The Iban language version of the folklores was officially launched by YBhg. Datu Sudarsono Osman, on 10th of August 2015. It has since been translated into English and both are now available for purchase at WCS and selected outlets in Sarawak (WCS n.d.).	Ongoing
11. Habitat Protection	11.2. Legally protect primate habitat	In 2013, two study sites, Ulu Katibas and Ulu Pasin were gazetted as extensions to the Lanjak-Entimau Wildlife Sanctuary (WCS n.d.). In addition, Batang Ai is a National Park.	2013
12. Species Management	Not reported
13. Livelihood; Economic & Other Incentives	Not reported

Conservation activities list (Junker et al. 2017)

Challenges

The local community is reluctant to collaborate in patrols as field guides or assistants, because of a perceived view that, as a corporate entity, SFC was focussed on reducing losses, making profit, and increasing efficiency. The perceived view by the communities was also because of reduced numbers of park staff at Batang Ai National Park and Lanjak-Entimau Wildlife Sanctuary, removal of the staff/village rotation system of hiring local communities, and less permanent and contract staff to work at the park (Pandong 2019).

Table 5. Challenges reported for Batang Ai-Lanjak-Entimau (BALE) landscape

Challenge	Source
Lack of law enforcement	Pandong 2019
Lack of trust and support from local communities	Pandong 2019

Research activities

Documented behaviours

Table 6. Ape behaviors reported for Batang Ai-Lanjak-Entimau (BALE) landscape

Behavior	Source
Not reported

External links

WCS Malaysia

Relevant datasets

A.P.E.S Portal

References

Pandong, J., Gumal, M., Alen, L. et al. (2018).Population estimates of Bornean orang-utans using Bayesian analysis at the greater Batang Ai-Lanjak-Entimau landscape in Sarawak, Malaysia. Sci Rep 8, 15672. https://doi.org/10.1038/s41598-018-33872-3
Pandong, J. (2019). Conservation Ecology of Bornean Orangutans in the Greater Batang AiLanjak-Entimau Landscape, Sarawak, Malaysia [Master's thesis, The University of Adelaide].
Gurmaya, K.J. & Sundai, S. (2002). Development of Lanjak Entimau Wildlife Sanctuary as a totally protected area. Phase III. ITTO Project PD 16/99 Rev.2 (F).: A study of habitat conditions, populations, and distribution of orangutans in Lanjak Entimau Wildlife Sanctuary and Batang Ai National Park, Sarawak, Malaysia. International Tropical Timber Organization, Yokohama, Japan and Forest Department Sarawak. Malaysia.
Wich, S.A., E. Meijaard, A.J. Marshall, et al. (2008). Distribution and conservation status of the orang-utan (Pongo spp.) on Borneo and Sumatra: how many remain? Oryx. 42:329–339.
Voigt, Maria, Wich, Serge A., Ancrenaz, Marc, Meijaard, Erik, Abram, Nicola, Banes, Graham L., Campbell-Smith, Gail, d’Arcy, Laura J., Delgado, Roberto A., Erman, Andi, and others. (2018). Global Demand for Natural Resources Eliminated More Than 100,000 Bornean Orangutans. Current Biology, 28 (5). pp. 761-769. ISSN 0960-9822. (doi:10.1016/j.cub.2018.01.053) (KAR id:66068)
WCS. (n.d.).WORKING TOWARDS CONSERVING ORANG-UTANS AND THEIR HABITATS.https://malaysia.wcs.org/Wild-Places/Working-towards-conserving-orang-utans-and-their-habitats.aspx
WCS. (n.d.). Orang-utan.https://malaysia.wcs.org/Wildlife/Orang-utan-conservation-in-Sarawak.aspx

Page completed by: A.P.E.S. Wiki team Date: 24/10/2021