Thomas’s Langur Presbytis thomasi
Vulnerable
Sumatra, Indonesia
The Thomas’s Langur is a species of primate that has been recorded from undisturbed primary rainforest near Ketambe Research Station in Sumatra (Sterck et al. 2005). They have also been recorded from a mosaic of primary and secondary forest with rubber plantations on its fringes (Wich and de Vries 2006), and in rubber tree plantations (Gurmaya 1986). Also found in lowland alluvial, riparian forests. Despite their presence in lowland alluvial and riparian habitats, their densities are higher in swamp forest compared to the former and tolerate selectively logged forest.
They live in ranges in elevation from 0 to approximately 1,500 m. Known to occur in elevations of 1,500-2,400 m and in lower sub-alpine zone up to 3,400 m in the Leuser Ecosystem.
The Thomas’s Langur is vulnerable on @IUCNredlist due to forest clearance for #palmoil in #Sumatra #Indonesia. Protect this beautiful #monkey with a #Boycott4Wildlife on brands destroying forests
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Hunting does not seem to be a significant threat, but loss of primary habitat due to logging and conversion to oil palm plantations is probably displacing some populations.
IUCN Red List
Though protected by the local Batak traditional and religious taboos, there is some ‘marginal’ hunting pressure in the other parts of their distribution. The Thomas’s Langur is considered Vulnerable due to past and continued population declines, estimated at more that 30% over the past 40 years (three generations) due to loss of habitat, especially to logging and oil palm plantations. Due to continuing threats, the Thomas’s Langur is suspected to decline at the same rate over the next one generation.
Further Information

Setiawan, A. & Traeholt, C. 2020. Presbytis thomasi. The IUCN Red List of Threatened Species 2020: e.T18132A17954139. https://dx.doi.org/10.2305/IUCN.UK.2020-2.RLTS.T18132A17954139.en. Downloaded on 24 January 2021.
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