Javan langur

Scientific name:

Trachypithecus auratus

Threat level:

Vulnerable

Authority:

É. Geoffroy, 1812

Common names:

• Ebony leaf monkey (English)
• Javan lutung (English)
• Javan langur (English)

Taxonomy:

There is disagreement over the validity and physical separation of the subspecies. Designations of subspecies are not well defined, and a genetic study refutes the assignment of any (Rosenblum et al. 1997).

Taxonomy synonyms:

Version:

3.1

Year assessed:

2008

Assessor(s):

Nijman, V. & Supriatna, J.

Evaluator(s):

Mittermeier, R.A. & Rylands, A.B. (Primate Red List Authority)

Justification:

This species is considered Vulnerable due to a past and continued population decline, estimated at more than 30% over the past 36 years (3 generations, given a generation length of 12 years), as a result of capture for the illegal pet trade, hunting, and loss of habitat.

Geographic ranges:

• Indonesia (Native)

Population:

This species was the most frequently observed primate during a survey of the Dieng Mountains in central Java (Nijman and van Balen 1998). Nijman and van Balen (1998) reported it to be rather common on both Mount Prahu and the central part of the study area in the Pegunungan Dieng Mountains where they also estimate a density of 23 individuals/km². From a review of 14 studies, densities were estimated as following: 7.9 (+/- 8.8) groups/km², and individuals estimated at 114 (+/- 147.9) groups/km² (E. Meijaard and V. Nijman pers. comm.).

Population trend:

Decreasing

Habitat and ecology:

T. auratus occurs in mangrove, beach, and freshwater swamp forests, ever-wet lowland and hill forests, dry deciduous forests, and montane forest up to 3,000-3,500 m (Nijman 2000), in addition to teak, rasamala, and acacia forest plantations.

It is mostly folivorous, preferring to eat leaves and flowers, though it will consume the seeds of fruits and unripened fruits as well (Nijman 2000). In the Dieng Mountains of central Java, it has been recorded from both primary and secondary forest, both on the edges and in the interior (Nijman and van Balen 1998). Home range was calculated by Kool (1993) to be 20-30 ha and may be bigger in Java.

Ecosystems

• Terrestrial

List of habitats:

• Forest
• Subtropical/Tropical Dry
• Subtropical/Tropical Moist Lowland
• Subtropical/Tropical Mangrove Vegetation Above High Tide Level
• Subtropical/Tropical Moist Montane
• Artificial/Terrestrial
• Plantations

Major threats:

Threats include habitat loss and degradation due to expanding agriculture and human settlements, hunting for food and increasingly for the pet trade, fragmentation, and small isolated populations.

List of threats:

• Residential & commercial development
• Housing & urban areas
• Agriculture & aquaculture
• Annual & perennial non-timber crops
• Small-holder farming
• Biological resource use
• Hunting & trapping terrestrial animals
• Intentional use (species is the target)

Conservation actions:

This species is listed under CITES Appendix II, and has been protected by Indonesian law since 1999. It has been recorded from Pangandaran Nature Reserve (Watanabe et al. 1996), Gunung Halimun and Ujung Kulon National Park (Gurmaya et al. 1994), and is one of the more common and thriving colobines in captivity.

List of conservation actions:

• Land/water protection
• Site/area protection
• Resource & habitat protection
• Land/water management
• Site/area management
• Species management
• Species management
• Harvest management
• Trade management
• Education & awareness
• Awareness & communications
• Law & policy
• Legislation
• National level