Pongo pygmaeus ssp. pygmaeus
|Scientific Name:||Pongo pygmaeus ssp. pygmaeus (Linnaeus, 1760)|
See Pongo pygmaeus
Pongo pygmaeus pygmaeus is one of the three subspecies of Bornean orangutan currently recognized (Goossens et al. 2009). This taxon is found in the State of Sarawak (Malaysia), and in the Province of West Kalimantan (Indonesia).
|Red List Category & Criteria:||Critically Endangered A4abcd ver 3.1|
|Assessor(s):||Ancrenaz, M., Gumal, M., Marshall, A.J., Meijaard, E., Wich , S.A. & Husson, S.|
|Reviewer(s):||Williamson, L. & Mittermeier, R.A.|
This taxon has the smallest range of the three Bornean Orangutan subspecies found in Borneo (Wich et al. 2008, Wich et al. 2012). Fewer than 10,000 individuals remain in Sarawak and West Kalimantan. Although several major populations reside in protected areas, illegal hunting remains a major threat to their survival over most of the range occupied by P. p. pygmaeus (Abram et al. 2015). In addition, large numbers that existed on the western side of West Kalimantan have been lost due to recent forest conversion to oil palm agriculture and poaching (Abram et al. 2015). Encounter rates of the subspecies appear to have declined six-fold in the past 150 years, even in areas which remain forested, indicating that factors like hunting are driving declines (Meijaard et al. 2010). This subspecies is declining fast, with the combined impacts of climate and land-use change expected to cause further rapid losses of suitable habitat (Struebig et al. 2015). Rate of forest loss was about 30% over a 17-year period: 1995–2002 (Rijksen and Meijaard 1999, Wich et al. 2008, Gaveau et al. 2014) plus the subspecies experiences medium-level rates of killing (Meijaard et al. 2011). Only the populations in the Lanjak Entimau/Batang Ai complex and those in Betung Kerihun National Park are relatively safe, but the majority of orangutans in the lower lying swamp and lowland Dipterocarp forests are under very high pressure from habitat loss, conflict killing and hunting. In Sarawak, two small populations are now found only in the protected peat swamp forests of Sebuyau and Sedilu.
|Previously published Red List assessments:|
|Range Description:||Pongo p. pygmaeus occurs in West Kalimantan (Indonesia) from north of the Kapuas River to the eastern part of Sarawak (Malaysia). Core populations are centred around the following protected areas: Batang Ai National Park/Lanjak Entimau Wildlife Sanctuary complex in Sarawak; and Betung Kerihun and Danau Sentarum National Parks in West Kalimantan (Wich et al. 2008). Two additional small populations in Ulu Sebuyau National Park and Sedilu National Park in Sarawak were officially protected in 2010.|
Native:Indonesia (Kalimantan); Malaysia (Sarawak)
|Range Map:||Click here to open the map viewer and explore range.|
Climatic change and human pressure have resulted in significant reductions in the range and numbers of Northwest Bornean Orangutans during the recent historic past (Goossens et al. 2006, Meijaard et al. 2010).
|Current Population Trend:||Decreasing|
|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:||For information on use and trade, see under Threats.|
Major threats include:
The 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.
|Citation:||Ancrenaz, M., Gumal, M., Marshall, A.J., Meijaard, E., Wich , S.A. & Husson, S. 2016. Pongo pygmaeus ssp. pygmaeus. The IUCN Red List of Threatened Species 2016: e.T39781A17990445.Downloaded on 22 March 2018.|