Pongo pygmaeus ssp. morio 

Scope: Global
Language: English

Translate page into:

Taxonomy [top]

Kingdom Phylum Class Order Family
Animalia Chordata Mammalia Primates Hominidae

Scientific Name: Pongo pygmaeus ssp. morio (Owen, 1837)
Parent Species:
Common Name(s):
English Northeast Bornean Orangutan
Taxonomic Notes:

Pongo pygmaeus morio is one of the three subspecies currently recognized for the Bornean Orangutan (Goossens et al. 2009). This subspecies is found in the State of Sabah (Malaysia), and in the Provinces of North Kalimantan and East Kalimantan (Indonesia).

Assessment Information [top]

Red List Category & Criteria: Critically Endangered A4abcd ver 3.1
Year Published: 2016
Date Assessed: 2016-02-08
Assessor(s): Ancrenaz, M., Gumal, M., Marshall, A.J., Meijaard, E., Wich , S.A. & Husson, S.
Reviewer(s): Mittermeier, R.A. & Williamson, L.

Fewer than 20,000 Northeast Bornean Orangutans remain, mostly in Sabah and East Kalimantan, with a few scattered groups in North Kalimantan.

In Sabah, genetic evidence shows that more than 90% of the original orangutan population was lost over the past 200 years due to human activities (Goossens et al. 2006). With 39.5% forest loss in a 40-year period (1973–2010), the State has experienced the highest rate of forest loss in Borneo (Gaveau et al. 2014). Most of this loss has occurred in the eastern lowland forests that used to be the preferred orangutan habitat. Although about 80% of orangutans are currently found in protected forests, many populations are still declining because of further land conversion, killing and forest fragmentation. A new study estimates that in the past 10 years alone, the total number of orangutans in the State has declined by about 25% (Santika et al. submitted).

Populations in Kalimantan have suffered a similar fate due a combination of (illegal) hunting pressure, forest fires and forest conversion to agriculture. Models of perceived population trends for this subspecies in Kalimantan predict orangutan declines and local extinctions in the next 10 years (Abram et al. 2015). Indeed, in most of the areas of East Kalimantan occupied by orangutans, risk of conflict is high and this is likely to reflect pressures caused by rapid natural land-cover conversion to plantations. This subspecies is declining fast, and the combined impacts of climate and land-use changes are expected to result in further rapid loss of suitable habitat (Struebig et al. 2015). Fires compound the declines: for example, 90% of Kutai National Park was lost to massive fires in 1983 and 1998 and its orangutan population was reduced from about 4,000 individuals in the 1970s (Rijksen and Meijaard 1999) to a mere 600 (Wich et al. 2008).

In sum, more than 86% of this subspecies will be lost in three generations (1950–2025) hence this subspecies is listed as Critically Endangered. See species-level assessment for further details (Pongo pygmaeus).

Previously published Red List assessments:

Geographic Range [top]

Range Description:The Northeast Bornean Orangutan is endemic to the island of Borneo where it is present in the two Malaysian states of Sabah and Sarawak, as well as in two of the five Indonesian Provinces of Kalimantan: North and East Kalimantan. The remaining Northeast Bornean Orangutan are found primarily in Sabah and East Kalimantan, with a few scattered groups in North Kalimantan.
Countries occurrence:
Indonesia (Kalimantan); Malaysia (Sabah)
Additional data:
Upper elevation limit (metres):500
Range Map:Click here to open the map viewer and explore range.

Population [top]


In the early 2000s, 16 major populations of P. p. morio were recognized in Sabah (Ancrenaz et al. 2005). Today, 80% of orangutans in Sabah occur in protected forests, but most populations are still declining as a result of habitat loss and fragmentation (Bruford et al. 2010, Santika et al. submitted). The impacts of climate change are expected to reinforce this trend (Gregory et al. 2012, Wich et al. 2015).

In Kalimantan, most populations of P. p. morio are found outside of protected areas in forests that are earmarked for conversion to other land uses (Wich et al. 2012). Forest conversion and the ensuing high rate of conflicts will lead to further declines in this subspecies (Abram et al. 2015).

See species-level assessment for more information (Pongo pygmaeus).

Current Population Trend:Decreasing
Additional data:
Continuing decline of mature individuals:Yes
Extreme fluctuations:NoPopulation severely fragmented:Yes
All individuals in one subpopulation:No

Habitat and Ecology [top]

Habitat and Ecology:

Bornean Orangutans are the largest arboreal mammals in the world, although they walk significant distances on the ground (Ancrenaz et al. 2014). Historically, Bornean Orangutans were most abundant in inundated and semi-inundated lowland Dipterocarp mosaic forests, where movement between different habitat types could buffer them against shortages in food availability in a particular habitat type. Their diet consists primarily of fruits, but also includes leaves, barks, flowers and insects (Russon et al. 2009).

Bornean Orangutans live a semi-solitary life and rarely aggregate in groups. Males are the dispersing sex: upon reaching sexual maturity (at 10–12 years old), they leave the area where they were born to establish large territories covering several hundred hectares. Females’ territories are smaller, with actual size depending on forest type and availability of food resources. Bornean Orangutans are very slow breeders and produce on average one offspring every 6–8 years, which explains their extreme sensitivity to hunting pressure. Females reach maturity at 10–15 years old; they generally give birth to a single infant after a gestation period of approximately 254 days (Kingsley 1981).

Continuing decline in area, extent and/or quality of habitat:Yes
Generation Length (years):25
Movement patterns:Not a Migrant

Use and Trade [top]

Use and Trade: For information on use and trade, see under Threats.

Threats [top]

Major Threat(s): Major threats include:
  1. Habitat loss. Between 2000 and 2010, the mean annual rate of deforestation for Borneo was 3,234 km2 per year (Gaveau et al. 2014). Assuming a similar deforestation rate in the future, 32,000 km2 of forest could be lost by 2020; 129,000 km2 by 2050 and 226,000 km2 by 2080 (Wich et al. 2015). In the early 2010s, only 22% of the current Bornean Orangutan distribution was located in protected areas (Wich et al. 2012). Approximately a third of the entire Bornean orangutan range was in commercial forest reserves exploited for timber, and about 45% was in forest areas earmarked for conversion to agriculture or other land uses. A business-as-usual scenario, whereby non-protected forests would be converted along the lines of current development plans, will result in the loss of more than half of the current orangutan range on the island of Borneo in the next 50 years or so.
  2. Illegal hunting. Illegal killing of Northeast Bornean Orangutans is a major cause of their decline. Recent interview surveys conducted in Kalimantan revealed that several thousand individuals are killed every year for meat consumption, as a way to mitigate conflict, or for other reasons (Davis et al. 2013). Overall Bornean Orangutan mortality rates in Kalimantan seem to significantly exceed the maximum rates that populations of this slow-breeding species can sustain (Marshall et al.  2009, Meijaard et al.  2011). If hunting does not stop, all populations that are hunted will decline, irrespective of what happens to their habitat. These findings confirm that habitat protection alone will not ensure the survival of orangutans in Indonesian Borneo, and that effective reduction of orangutan killings is urgently needed.
  3. Fires. Fires occur in Borneo on a yearly basis and are responsible for significant forest loss with dramatic results for certain orangutan populations. For example, 90% of Kutai National Park was lost to massive fires in 1983 and 1998 and its Bornean Orangutan population was reduced from an estimated 4,000 individuals in the 1970s to a mere 600 (Rijksen and Meijaard 1999); over 4,000 km2 of peatland forest in southern Kalimantan was burnt to ashes in six months of 1997–1998, resulting in an estimated loss of 8,000 orangutans. In 2015, more than 20,000 km2 of forest were lost to fires, which resulted in hundreds (or more) of additional orangutan deaths.
  4. Habitat fragmentation. With the current scale of habitat exploitation and forest conversion to other types of land uses in Borneo, only a small percentage of current orangutan habitat will remain undisturbed by infrastructure development by 2030 (Gaveau et al. 2013). Several orangutan PHVAs have shown that Bornean Orangutan populations of fewer than 50 individuals are not viable in the long term (Marshall et al. 2009), and that many small populations will go extinct unless they are actively managed (Bruford et al. 2010).
  5. Lack of awareness. A recent study suggested that 27% of the people in Kalimantan did not know that orangutans are protected by law (Meijaard et al.  2011). Campaigns to effectively inform the public and encourage rural people to support the principles of environmental conservation and be actively responsible for the management of their resources are therefore a crucial requirement for successful orangutan conservation.
  6. Climate change. Spatial models point to the possibility that a large amount of current orangutan habitat will become unsuitable because of changes in climate (Struebig et al. 2015). Across all climate and land-cover change projections assessed in a recent analysis, models predicted that 49,000–83,000 km2 of orangutan habitat will remain by 2080, reflecting a loss of 69–81% since 2010. This projection represents a three to five-fold greater decline in habitat than that predicted by deforestation projections alone. A major reduction in the extent of suitable orangutan habitat can be expected. However, core strongholds of suitable orangutan habitat are predicted to remain to the west, east and northeast of the island where populations of P. p. wurmbii and P. p. morio are found.

Conservation Actions [top]

Conservation Actions:

The Northeast Bornean Orangutan is fully protected in Malaysia and Indonesia, and is listed on Appendix I of CITES. However, its forest habitat is not necessarily protected: about 20% of the current orangutan range in Sabah, and 80% in Kalimantan is not protected (Wich et al. 2012). Innovative mechanisms to ensure the long-term survival of Bornean Orangutans outside protected forests are urgently needed.

The future of Bornean Orangutans will very much depend on the long-term security of large, strictly-protected forests where illegal logging and hunting will be efficiently controlled and the orangutan populations large enough to cope with catastrophic events such as fires and disease outbreaks (Meijaard et al. 2011). These forests need to contain the ecological gradients that will provide the key resources to sustain orangutans through climate and other gradual environmental changes (Gregory et al. 2012). In the larger landscape, scientifically-based, regional land-use planning is needed to delineate zones of interaction around protected forests and their surroundings, encompassing hydrological, ecological and socio-economic interactions. Ideally, the core protected areas will remain connected to other areas of forest that could be used sustainably for (commercial) timber extraction. The design of such living landscapes must be approached across the whole landscape rather than at the site level.

Citation: Ancrenaz, M., Gumal, M., Marshall, A.J., Meijaard, E., Wich , S.A. & Husson, S. 2016. Pongo pygmaeus ssp. morio. The IUCN Red List of Threatened Species 2016: e.T63544A17990681. . Downloaded on 17 August 2018.
Disclaimer: To make use of this information, please check the <Terms of Use>.
Feedback: If you see any errors or have any questions or suggestions on what is shown on this page, please provide us with feedback so that we can correct or extend the information provided