Difference between revisions of "Leuser Ecosystem"

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[[Asia]] > [[Indonesia]] > [[Leuser Ecosystem]]
 
[[Asia]] > [[Indonesia]] > [[Leuser Ecosystem]]
−
 
−
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= Summary = <!-- An overview of the site, with one sentence for each section. May include a site map -->
 
= Summary = <!-- An overview of the site, with one sentence for each section. May include a site map -->
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* The site has a total size of 2.6 million ha.
 
* The site has a total size of 2.6 million ha.
 
* Key threats to orangutans are deforestation, construction of roads and planned construction of hydroelectric power plants, poaching, and capturing of young orangutans for the illegal pet trade.
 
* Key threats to orangutans are deforestation, construction of roads and planned construction of hydroelectric power plants, poaching, and capturing of young orangutans for the illegal pet trade.
−
* Several NGOs are involved in the implementation of conservation interventions; for example, the Human-Orangutan Conflict Response Unit rescues and relocates orangutans trapped by humans.
+
* Several NGOs are involved in the implementation of conservation interventions; for example, the Human-Orangutan Conflict Response Unit rescues and relocate orangutans trapped by humans.
  
 
= Site characteristics = <!-- A paragraph summary of physical and geographic aspects of the site, and a table of key information -->
 
= Site characteristics = <!-- A paragraph summary of physical and geographic aspects of the site, and a table of key information -->
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'''Table 1. Basic site information for Leuser Ecosystem'''
 
'''Table 1. Basic site information for Leuser Ecosystem'''
 
{| border="1" cellpadding="5" cellspacing="0" class="basic-information"
 
{| border="1" cellpadding="5" cellspacing="0" class="basic-information"
−
| Species
+
| Area <!-- Please include units: km2/ha e.g 200ha -->
−
|''Pongo abelii''
+
|2.6 million ha
−
|-
 
−
| Area
 
−
|26000 km²
 
 
|-
 
|-
 
|Coordinates
 
|Coordinates
−
|3.630896, 97.378969
+
|3.630896 N, 97.378969 E
−
|-
 
−
|Type of site
 
−
|Conservation area (National Strategic Area)
 
 
|-
 
|-
−
|Governance type
+
|Designation
−
|Governance by government
+
|National Strategic Area
 
|-
 
|-
−
|Habitat type
+
|Habitat types <!-- List IUCN Habitat Classification 3.0 categories present (without number), see link below -->
 
|Subtropical/tropical dry forest, plantations, subtropical/tropical heavily degraded former forest
 
|Subtropical/tropical dry forest, plantations, subtropical/tropical heavily degraded former forest
 
|}
 
|}
−
[[Types of sites]] ⋅ [[Governance types]] ⋅ [[Habitat types]]
+
[https://www.iucnredlist.org/resources/habitat-classification-scheme IUCN habitat categories] [[Site designations]]
 
<div><ul>
 
<div><ul>
 
<li style="display: inline-block; vertical-align: top;"> [[File: Sumatran orangutan in Leuser Perry van Duijnhoven.JPG | 300px | thumb| right |Sumatran orangutan © Perry van Duijnhoven]] </li>
 
<li style="display: inline-block; vertical-align: top;"> [[File: Sumatran orangutan in Leuser Perry van Duijnhoven.JPG | 300px | thumb| right |Sumatran orangutan © Perry van Duijnhoven]] </li>
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! Species
 
! Species
 
! Year
 
! Year
−
! Occurrence
 
−
! Encounter or visitation rate (nests/km; ind/day)
 
−
! Density estimate [ind/ km²] (95% CI)
 
 
! Abundance estimate (95% CI)
 
! Abundance estimate (95% CI)
−
! Survey area
+
! Density estimate [ind./ km²] (95% CI)
−
! Sampling method
+
! Encounter rate (nests/km)
−
! Analytical framework
+
! Area
 +
! Method
 
! Source
 
! Source
 
! Comments
 
! Comments
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|''Pongo abelii''
 
|''Pongo abelii''
 
|1999-2013
 
|1999-2013
−
|Present
+
|13,846 (11,561-16,805)
 +
|0.73
 
|
 
|
−
|0.73
 
−
|13846 (11561-16805)
 
 
|Leuser Ecosystem
 
|Leuser Ecosystem
−
|Line transects
+
|Line transects (Distance)
−
|
 
 
|Wich et al. 2016
 
|Wich et al. 2016
 
|
 
|
 
|
 
|
 
|}
 
|}
−
[[Sampling methods]] ⋅ [[Analytical frameworks]]
 
  
 
= Threats =    <!-- a text overview of threats, followed by a table of key threats -->
 
= Threats =    <!-- a text overview of threats, followed by a table of key threats -->
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Key threats to orangutans at the Leuser Ecosystem include habitat destruction, habitat fragmentation, hunting, and the illegal pet trade ([https://www.sumatranorangutan.org/sumatran-orangutans/threats/ SOCP]). New roads are continuously being cut through the habitat. In addition to habitat encroachment, palm oil concessions, and new hydro electric schemes and geothermal energy plants are proposed in critical areas ([https://www.sumatranorangutan.org/sumatran-orangutans/threats/ SOCP]). As a by-product of land-conversion and increased proximity to humans, orangutans are sometimes killed due to human-wildlife conflict situations, for example, when orangutans raid farmlands (Singleton et al. 2018).
 
Key threats to orangutans at the Leuser Ecosystem include habitat destruction, habitat fragmentation, hunting, and the illegal pet trade ([https://www.sumatranorangutan.org/sumatran-orangutans/threats/ SOCP]). New roads are continuously being cut through the habitat. In addition to habitat encroachment, palm oil concessions, and new hydro electric schemes and geothermal energy plants are proposed in critical areas ([https://www.sumatranorangutan.org/sumatran-orangutans/threats/ SOCP]). As a by-product of land-conversion and increased proximity to humans, orangutans are sometimes killed due to human-wildlife conflict situations, for example, when orangutans raid farmlands (Singleton et al. 2018).
 
<div><ul>
 
<div><ul>
−
<li style="display: inline-block; vertical-align: top;"> [[File: Deforestation_for_small_scale_agriculture_in_Leuser_Perry_van_Duijnhoven.jpg | 300px | thumb| right |Deforestation for small scale agriculture © Perry van Duijnhoven]] </li>
+
<li style="display: inline-block; vertical-align: top;"> [[File: Deforestation_for_small_scale_agriculture_in_Leuser_Perry_van_Duijnhoven.jpg | 300px | thumb| right |Deforestation for small scale agiriculture © Perry van Duijnhoven]] </li>
 
<li style="display: inline-block; vertical-align: top;"> [[File: Draining_canals_in_peat_swamp_Leuser_Perry_van_Duijnhoven.jpg | 300px | thumb| right | Draining canals in peat swamp © Perry van Duijnhoven]] </li>
 
<li style="display: inline-block; vertical-align: top;"> [[File: Draining_canals_in_peat_swamp_Leuser_Perry_van_Duijnhoven.jpg | 300px | thumb| right | Draining canals in peat swamp © Perry van Duijnhoven]] </li>
 
<li style="display: inline-block; vertical-align: top;"> [[File: Small_scale_logging_Leuser_Perry_van_Duijnhoven.jpg | 300px | thumb| right |Small-scale logging © Perry van Duijnhoven]] </li>
 
<li style="display: inline-block; vertical-align: top;"> [[File: Small_scale_logging_Leuser_Perry_van_Duijnhoven.jpg | 300px | thumb| right |Small-scale logging © Perry van Duijnhoven]] </li>
 
</ul></div>
 
</ul></div>
−
 
 
'''Table 3. Threats to apes in Leuser Ecosystem'''
 
'''Table 3. Threats to apes in Leuser Ecosystem'''
 
{| border="1" cellpadding="5" cellspacing="0" class="threats-table"
 
{| border="1" cellpadding="5" cellspacing="0" class="threats-table"
 
!align="left"|Category <!-- PLEASE DO NOT CHANGE THE THREAT CATEGORIES -->
 
!align="left"|Category <!-- PLEASE DO NOT CHANGE THE THREAT CATEGORIES -->
−
!Specific threats
+
!Specific threats <!-- For specific threats, please use list of comma separated keywords from the IUCN list linked below -->
−
!Threat level
+
!Threat level <!-- For threat level, please use keywords: low, medium, high, present, absent, unknown-->
−
!Description
+
!Quantified severity <!-- Enter any available quantification of the threat, e.g., the proportion of the area affected by the threat, hunting sign encounter rates-->
−
!Year of threat
+
!Description <!-- Add descriptive information -->
 +
!Year of threat <!--  Enter specific year(s), “ongoing”, or “unknown”. If the threat is ongoing, please add the year of reference in parentheses -->
 
|-
 
|-
 
|1. Residential & commercial development
 
|1. Residential & commercial development
 
|
 
|
 
|Unknown
 
|Unknown
 +
|
 
|
 
|
 
|
 
|
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|
 
|
 
|Unknown
 
|Unknown
 +
|
 
|
 
|
 
|
 
|
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|3.3 Renewable energy
 
|3.3 Renewable energy
 
|Low
 
|Low
 +
|
 
|Proposed construction of several new hydroelectric power plants leading to habitat loss (Wich pers. comm. 2020; SOCP).
 
|Proposed construction of several new hydroelectric power plants leading to habitat loss (Wich pers. comm. 2020; SOCP).
 
|Ongoing (2020)
 
|Ongoing (2020)
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|4.1 Roads & railroads
 
|4.1 Roads & railroads
 
|Medium
 
|Medium
 +
|
 
|The construction of roads is causing forest loss and forest fragmentation (Wich et al. 2016).
 
|The construction of roads is causing forest loss and forest fragmentation (Wich et al. 2016).
 
|Ongoing (2016)
 
|Ongoing (2016)
 
|-
 
|-
 
|5. Biological resource use
 
|5. Biological resource use
−
|5.1.5 Persecution/human wildlife conflict
+
|5.1 Hunting & collecting terrestrial animals
 
|Low
 
|Low
−
|Poaching/persecution. Orangutans are captured or killed when they leave the forest and enter agricultural land or areas that have been recently deforested (Wich et al 2016; Singleton et al. 2018).
+
|
−
|2016-Ongoing (2018)
+
|Poaching/persecution. Orangutans are captured or killed when they leave the forest and enter
 +
agricultural land or areas that have been recently deforested (Wich et al 2016; Singleton et al. 2018).
 +
|Ongoing (2018)
 
|-
 
|-
−
|5. Biological resource use
+
|
−
|5.1.4 Capture for the live animal trade
 
−
|Present (unknown severity)
 
−
|Capturing young orangutans for illegal pet trade ([https://www.sumatranorangutan.org/sumatran-orangutans/threats/ SOCP]).
 
−
|Ongoing (2023)
 
−
|-
 
−
|5. Biological resource use
 
 
|5.3 Logging & wood harvesting
 
|5.3 Logging & wood harvesting
 
|Medium
 
|Medium
 +
|
 
|Deforestation as a result of land-cover changes (Wich et al. 2016).
 
|Deforestation as a result of land-cover changes (Wich et al. 2016).
 
|Ongoing (2016)
 
|Ongoing (2016)
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|
 
|
 
|Unknown
 
|Unknown
 +
|
 
|
 
|
 
|
 
|
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|
 
|
 
|Unknown
 
|Unknown
 +
|
 
|
 
|
 
|
 
|
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|
 
|
 
|Unknown
 
|Unknown
 +
|
 
|
 
|
 
|
 
|
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|
 
|
 
|Unknown
 
|Unknown
 +
|
 
|
 
|
 
|
 
|
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|
 
|
 
|Absent
 
|Absent
 +
|
 
|
 
|
 
|
 
|
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|
 
|
 
|Unknown
 
|Unknown
 +
|
 
|
 
|
 
|
 
|
 
|-
 
|-
 
|12. Other options
 
|12. Other options
 +
|12.1 Other threat
 +
|Present, but threat severity is unknown
 
|
 
|
−
|Absent
+
|Capturing young orangutans for illegal pet trade ([https://www.sumatranorangutan.org/sumatran-orangutans/threats/ SOCP]).
−
|
+
|Ongoing
−
|
 
 
|-
 
|-
 
|}
 
|}
−
[[Threats]]
+
[https://www.iucnredlist.org/resources/threat-classification-scheme IUCN Threats list]
  
 
= Conservation activities =      <!-- A summary of the conservation activities, followed by a table of key activities -->
 
= Conservation activities =      <!-- A summary of the conservation activities, followed by a table of key activities -->
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{| border="1" cellpadding="5" cellspacing="0" class="conservation-actions-table"
 
{| border="1" cellpadding="5" cellspacing="0" class="conservation-actions-table"
 
!align="left"|Category <!-- PLEASE DO NOT CHANGE THE CATEGORIES -->
 
!align="left"|Category <!-- PLEASE DO NOT CHANGE THE CATEGORIES -->
−
!Specific activity
+
!Specific activity <!-- For specific threats, please use list from the list linked below, OR enter “Not reported” -->
−
!Description  
+
!Description <!-- Add descriptive information -->
−
!Implementing organization
+
!Year of activity <!-- Add descriptive information -->
−
!Year of activity
+
|-
 +
|1. Residential & commercial development
 +
|1.2. Relocate primates to non-residential areas
 +
|The Human-Orangutan Conflict Response Unit rescue, relocate, and confiscate orangutans in human-orangutan conflict situations ([https://orangutancentre.org/rescueing-orangutan/ OIC]).
 +
|Ongoing
 
|-
 
|-
−
|1. Development impact mitigation
+
|2. Agriculture & aquaculture
 
|Not reported
 
|Not reported
−
|
 
 
|
 
|
 
|
 
|
 
|-
 
|-
−
|2. Counter-wildlife crime
+
|3. Energy production & mining
 
|Not reported
 
|Not reported
−
|
 
 
|
 
|
 
|
 
|
 
|-
 
|-
−
|3. Species health
+
|4. Transportation & service corridors
 
|Not reported
 
|Not reported
−
|
 
 
|
 
|
 
|
 
|
 
|-
 
|-
−
|4. Education & awareness
+
|5. Biological resource use
 
|Not reported
 
|Not reported
−
|
 
 
|
 
|
 
|
 
|
 
|-
 
|-
−
|5. Protection & restoration
+
|6. Human intrusion & disturbance
 
|Not reported
 
|Not reported
−
|
 
 
|
 
|
 
|
 
|
 
|-
 
|-
−
|6. Species management
+
|7. Natural system modifications
−
|6.7 Translocate (capture & release) wild apes from human impacted sites to natural habitat elsewhere
 
−
|The Human-Orangutan Conflict Response Unit rescue, relocate, and confiscate orangutans in human-orangutan conflict situations ([https://orangutancentre.org/rescueing-orangutan/ OIC]).
 
−
|
 
−
|Ongoing (2023)
 
−
|-
 
−
|7. Economic & other incentives
 
 
|Not reported
 
|Not reported
−
|
 
 
|
 
|
 
|
 
|
 
|-
 
|-
−
|8. Permanent presence
+
|8. Invasive & other problematic species, genes, diseases
 
|Not reported
 
|Not reported
−
|
 
 
|
 
|
 
|
 
|
 
|-
 
|-
−
|}
+
|9. Pollution
−
[[Conservation activities]]
 
−
 
 
−
= Conservation implementation challenges and enablers = <!-- Overview of challenges in ape conservation -->
 
−
 
 
−
'''Table 5. Challenges reported for Leuser Ecosystem'''
 
−
{| border="1" cellpadding="5" cellspacing="0" class="challenges-table"
 
−
!align="left"|Category <!-- PLEASE DO NOT CHANGE THE CATEGORIES -->
 
−
!Challenge
 
−
!Source
 
−
!Year(s)
 
−
|-
 
−
|1. Site management
 
−
|1.2 Need for improved coordination
 
−
|Wich pers. comm. 2020
 
−
|
 
−
|-
 
−
|2. Resources & capacity
 
 
|Not reported
 
|Not reported
 
|
 
|
 
|
 
|
 
|-
 
|-
−
|3. Engaged community
+
|10. Education & Awareness
 
|Not reported
 
|Not reported
 
|
 
|
 
|
 
|
 
|-
 
|-
−
|4. Institutional support
+
|11. Habitat Protection
−
|4.1 Lack of law enforcement
+
|Not reported
−
|Singleton et al. 2018
 
 
|
 
|
−
|-
 
−
|4. Institutional support
 
−
|4.3 Lack of protected area status
 
−
|Singleton et al. 2018
 
 
|
 
|
 
|-
 
|-
−
|5. Ecological context
+
|12. Species Management
 
|Not reported
 
|Not reported
 
|
 
|
 
|
 
|
 
|-
 
|-
−
|6. Safety & stability
+
|13. Livelihood; Economic & Other Incentives
 
|Not reported
 
|Not reported
 
|
 
|
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|-
 
|-
 
|}
 
|}
−
[[Challenges]]
+
[[Conservation activities list (Junker et al. 2017)]]
 +
 
 +
= Challenges = <!-- Overview of challenges in ape conservation -->
  
−
'''Table 6. Enablers reported for Leuser Ecosystem'''
+
'''Table 5. Challenges reported for Leuser Ecosystem'''
−
{| border="1" cellpadding="5" cellspacing="0" class="enablers-table"
+
{| border="1" cellpadding="5" cellspacing="0" class="challenges-table"
−
!align="left"|Category <!-- PLEASE DO NOT CHANGE THE CATEGORIES -->
+
!align="left"|Challenge <!-- Do not change categories -->
−
!Enabler
+
!Source <!-- Source for challenge mentioned -->
−
!Source
 
−
!Year(s)
 
 
|-
 
|-
−
|1. Site management
+
|Lack of law enforcement
−
|Not reported
+
|Singleton et al. 2018
−
|
 
−
|
 
 
|-
 
|-
−
|2. Resources & capacity
+
|Lack of national protection
−
|Not reported
+
|Singleton et al. 2018
−
|
 
−
|
 
 
|-
 
|-
−
|3. Engaged community
+
|Lack of management
−
|Not reported
+
|Wich pers. comm. 2020
−
|
 
−
|
 
−
|-
 
−
|4. Institutional support
 
−
|Not reported
 
−
|
 
−
|
 
−
|-
 
−
|5. Ecological context
 
−
|Not reported
 
−
|
 
−
|
 
−
|-
 
−
|6. Safety & stability
 
−
|Not reported
 
−
|
 
−
|
 
 
|-
 
|-
 
|}
 
|}
−
[[Enablers]]
 
  
 
= Research activities = <!-- Overview of research activities -->
 
= Research activities = <!-- Overview of research activities -->
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===Documented behaviours===  <!-- List of any behaviours observed at the site, including citations -->
 
===Documented behaviours===  <!-- List of any behaviours observed at the site, including citations -->
  
−
'''Table 7. Ape behaviors reported for Leuser Ecosystem'''
+
'''Table 6. Ape behaviors reported for Leuser Ecosystem'''
 
{| border="1" cellpadding="5" cellspacing="0" class="behaviors-table"
 
{| border="1" cellpadding="5" cellspacing="0" class="behaviors-table"
 
!align="left"|Behavior
 
!align="left"|Behavior
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[https://orangutancentre.org/ OIC]<br>
 
[https://orangutancentre.org/ OIC]<br>
 
[https://www.sumatranorangutan.org/ SOCP]<br>
 
[https://www.sumatranorangutan.org/ SOCP]<br>
 +
 +
===Relevant datasets===
 +
[http://apesportal.eva.mpg.de/database/archiveMap A.P.E.S Portal]
  
 
= References =
 
= References =
 
Singleton, I., Wich , S.A., Nowak, M., Usher, G. & Utami-Atmoko, S.S. 2017. Pongo abelii (errata version published in 2018). The IUCN Red List of Threatened Species 2017: e.T121097935A123797627. http://dx.doi.org/10.2305/IUCN.UK.2017-3.RLTS.T121097935A115575085.en <br>
 
Singleton, I., Wich , S.A., Nowak, M., Usher, G. & Utami-Atmoko, S.S. 2017. Pongo abelii (errata version published in 2018). The IUCN Red List of Threatened Species 2017: e.T121097935A123797627. http://dx.doi.org/10.2305/IUCN.UK.2017-3.RLTS.T121097935A115575085.en <br>
 +
 
<br>
 
<br>
 
'''Page completed by: '''Serge Wich & A.P.E.S. Wiki team''' Date:''' 30/12/2020 <!-- If you don't want to add your name, you can add "A.P.E.S. Wiki team" -->
 
'''Page completed by: '''Serge Wich & A.P.E.S. Wiki team''' Date:''' 30/12/2020 <!-- If you don't want to add your name, you can add "A.P.E.S. Wiki team" -->

Latest revision as of 03:20, 22 July 2024

Asia > Indonesia > Leuser Ecosystem

Summary[edit]

Forest view in Leuser Ecosystem © Perry van Duijnhoven
  • Sumatran orangutans (Pongo abelii) are present in the Leuser Ecosystem.
  • It has been estimated that 13,846 (CI: 11,561-16,805) individuals occur in the site.
  • The orangutan population trend is decreasing.
  • The site has a total size of 2.6 million ha.
  • Key threats to orangutans are deforestation, construction of roads and planned construction of hydroelectric power plants, poaching, and capturing of young orangutans for the illegal pet trade.
  • Several NGOs are involved in the implementation of conservation interventions; for example, the Human-Orangutan Conflict Response Unit rescues and relocate orangutans trapped by humans.

Site characteristics[edit]

The site is located in the provinces of Aceh and North Sumatra, at the northernmost tip of Sumatra, Indonesia. The area is extremely rich in biodiversity; more than 200 mammal species, 580 bird species, and an estimated 10,000 plant species, including 17 endemic genera, can be found at the Leuser Ecosystem. Within Leuser, the coastal peat swamp forests of Tripa, Kluet, and Trumon-Singkil harbour the highest densities of orangutans. In addition to Sumatran orangutans, the Leuser Ecosystem is also home to the last remaining viable populations of Sumatran tigers, Sumatran rhinoceros, and Sumatran elephants (Sumatran Orangutan Conservation Programme). The Leuser Ecosystem is designated as a National Strategic Area for its environmental function. This designation does not exclude non-forest uses, but stresses the importance of sustainable management (Singleton et al. 2018). The Gunung Leuser National Park is found within the Leuser Ecosystem, which is also designated a Man and Biosphere Reserve, and is part of the Tropical Rainforest Heritage of Sumatra World Heritage Cluster Site by UNESCO (Singleton et al. 2018). The park supports only 25.3% of Sumatra’s Orangutans. Also within the Leuser Ecosystem, is the 1,025 km² Singkil Swamps Wildlife Reserve (Singleton et al. 2018).

Table 1. Basic site information for Leuser Ecosystem

Area 2.6 million ha
Coordinates 3.630896 N, 97.378969 E
Designation National Strategic Area
Habitat types Subtropical/tropical dry forest, plantations, subtropical/tropical heavily degraded former forest

IUCN habitat categories Site designations

  • Sumatran orangutan © Perry van Duijnhoven
  • Female orangutan © Perry van Duijnhoven
  • Flanged male Sumatran orangutan © Perry van Duijnhoven

Ape status[edit]

The peat-swamp forests of the Leuser Ecosystem hold the highest Sumatran orangutan densities (Wich et al. 2016). The species is predicted to decline across a variety of land-use scenarios; as many as 4,500 individuals could vanish by 2030 (Wich et al. 2016).

Table 2. Ape population estimates in Leuser Ecosystem

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 abelii 1999-2013 13,846 (11,561-16,805) 0.73 Leuser Ecosystem Line transects (Distance) Wich et al. 2016

Threats[edit]

Key threats to orangutans at the Leuser Ecosystem include habitat destruction, habitat fragmentation, hunting, and the illegal pet trade (SOCP). New roads are continuously being cut through the habitat. In addition to habitat encroachment, palm oil concessions, and new hydro electric schemes and geothermal energy plants are proposed in critical areas (SOCP). As a by-product of land-conversion and increased proximity to humans, orangutans are sometimes killed due to human-wildlife conflict situations, for example, when orangutans raid farmlands (Singleton et al. 2018).

  • Deforestation for small scale agiriculture © Perry van Duijnhoven
  • Draining canals in peat swamp © Perry van Duijnhoven
  • Small-scale logging © Perry van Duijnhoven

Table 3. Threats to apes in Leuser Ecosystem

Category Specific threats Threat level Quantified severity Description Year of threat
1. Residential & commercial development Unknown
2. Agriculture & aquaculture Unknown
3. Energy production & mining 3.3 Renewable energy Low Proposed construction of several new hydroelectric power plants leading to habitat loss (Wich pers. comm. 2020; SOCP). Ongoing (2020)
4. Transportation & service corridors 4.1 Roads & railroads Medium The construction of roads is causing forest loss and forest fragmentation (Wich et al. 2016). Ongoing (2016)
5. Biological resource use 5.1 Hunting & collecting terrestrial animals Low Poaching/persecution. Orangutans are captured or killed when they leave the forest and enter

agricultural land or areas that have been recently deforested (Wich et al 2016; Singleton et al. 2018).

Ongoing (2018)
5.3 Logging & wood harvesting Medium Deforestation as a result of land-cover changes (Wich et al. 2016). Ongoing (2016)
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 12.1 Other threat Present, but threat severity is unknown Capturing young orangutans for illegal pet trade (SOCP). Ongoing

IUCN Threats list

Conservation activities[edit]

A number of NGOs are active in the implementation of conservation activities, including the Sumatran Orangutan Conservation Programme (SOCP), the Orangutan Information Center (OIC), the Leuser International Foundation (LIF), and HAkA.

Table 4. Conservation activities in Leuser Ecosystem

Category Specific activity Description Year of activity
1. Residential & commercial development 1.2. Relocate primates to non-residential areas The Human-Orangutan Conflict Response Unit rescue, relocate, and confiscate orangutans in human-orangutan conflict situations (OIC). Ongoing
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 Not reported
11. Habitat Protection Not reported
12. Species Management Not reported
13. Livelihood; Economic & Other Incentives Not reported

Conservation activities list (Junker et al. 2017)

Challenges[edit]

Table 5. Challenges reported for Leuser Ecosystem

Challenge Source
Lack of law enforcement Singleton et al. 2018
Lack of national protection Singleton et al. 2018
Lack of management Wich pers. comm. 2020

Research activities[edit]

Documented behaviours[edit]

Table 6. Ape behaviors reported for Leuser Ecosystem

Behavior Source
Not reported

External links[edit]

Leuser International Foundation
HAkA
OIC
SOCP

Relevant datasets[edit]

A.P.E.S Portal

References[edit]

Singleton, I., Wich , S.A., Nowak, M., Usher, G. & Utami-Atmoko, S.S. 2017. Pongo abelii (errata version published in 2018). The IUCN Red List of Threatened Species 2017: e.T121097935A123797627. http://dx.doi.org/10.2305/IUCN.UK.2017-3.RLTS.T121097935A115575085.en


Page completed by: Serge Wich & A.P.E.S. Wiki team Date: 30/12/2020

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