SEAVR 2019: 042‐043
ISSN: 2424‐8525
Date of publication: 07 April 2019
Hosted online by ecologyasia.com

White‐fronted Langur Presbytis frontata
at Bukit Santuai, Kalimantan Tengah, Indonesia
Ika Yuni AGUSTIN & Arif SETIAWAN
ikayuni.agustin@gmail.com (Agustin), wawan5361@gmail.com (Setiawan)

Observers: Ika Yuni Agustin, Arif Setiawan, Salmah Widyastuti, Abrar Ramlan.
Photographs by: Ika Yuni Agustin; Arif Setiawan.
Subjects identified by: Ika Yuni Agustin, Arif Setiawan, Abrar Ramlan, Kasih P. Handayani.
Location: Bukit Santuai, Kotawaringin Timur, Sampit, Central Kalimantan, Indonesia.
Precise location of record: Lat 01° 43’ 12.65’’ S, Long 112° 22 ’56.90” E
Elevation: 61 metres amsl.
Habitat: Natural secondary forest surrounded by palm oil concession.
Date and time: 23 October 2018, ~08:30 hrs.
Identity of subjects: White‐fronted Langur, Presbytis frontata (Mammalia: Primates: Cercopithecidae).
Description of record: Two individuals of White‐fronted Langur were seen foraging in secondary forest near apalm oil plantation, along an ex‐logging road running through the Bukit Santuai forest (Fig. 1 and inset). Themonkeys were about 40 meters from our location, at a height of around 25 metres, and were observed for 5
minutes whilst they were eating young leaves. After 5 minutes, the monkeys climbed down the tree, and wereout of view. One of the monkeys appeared to be an adult, and the other a sub‐adult (based on its smaller size).

© Ika Yuni Agustin and Arif Setiawan (inset)

Fig. 1 and inset(The red arrow is pointing at the tail of the sub‐adult)42Remarks: These two primates are identified as White‐fronted Langur Presbytis frontata based on the white spot
on the forehead, which distinguishes the species from other primates in the area, such as the Maroon Langur
Presbytis rubicunda which were also observed in the area. This endemic primate is one of the little‐known
primate species in Borneo (Meijaard & Nijman, 2008).
Bukit Santuai appears to lie in the south and west of the historical known range of the White‐fronted Langur(Phillipps & Phillips, 2016, page 165). The southernmost parts of Bukit Santuai forest lie around 30 km northeastof the town of Sukamandang, Central Kalimantan (= Kalimantan Tengah). It is considered an area of High
Conservation Value (HCV).
According to Roundtable on Sustainable Palm Oil (RSPO) criteria, Bukit Santuai fulfills the criteria to be included inseveral types of HCV i.e. HCV. 1.2 (endangered species component), HCV 1.3 (areas that contain habitat for viable
populations of endangered, restricted range or protected species), HCV 2.3 (areas that contain representative
populations of most naturally occurring species), HCV 3 (rare or endangered ecosystems) and HCV 6 (areas criticalfor maintaining the cultural identity of local communities) (PT Agro Wana Lestari, 2014).
This is the first finding of these rare leaf monkeys in the Bukit Santuai area, which is close to a palm oil plantation.
Based on IUCN assessment, this primate, which is listed as ‘vulnerable’, is found occasionally in secondary andplantation habitat (but the type of ‘plantation’ is not specified). Threats to this species come from habitat loss
and hunting, both for meat and for traditional medicine.
This primate occurs in the patchy forest in central and eastern Borneo, from central Sarawak to the southerncoast and is also found in the west (Meijaard & Nijman, 2008). Two individuals of these colobine monkeys werealso sighted in the upper parts of the Telen River in East Kalimantan during a 2009 field survey (A. Setiawan, pers.
comm., February 19, 2019). The species was also reported as occurring in Sungai Wain protection forest, near
Balikpapan (Bersacola et.al, 2014), and in the upper parts of the Barito River, Central Kalimantan (van Berkelet.al., 2012).
References:
Bersacola, E., Smith, D.E., Sastramidjaja, W.J., Rayadin, Y. and Cheyne, S.M. (2014). Population density of Presbytis
rubicunda in a small primary dipterocarp forest in East Kalimantan, Indonesian Borneo. Asian Primates J, 4, pp.16‐
26.
Ibie, B. F., Yulianti, N., Rumbang, N. & Ibie, E. (2016). Central Kalimantan High Conservation Value ProvincialAssessment: Identification and Mapping of High Conservation Values 1.1, 2.1, 2.2, 3 and 4.2. Palangkaraya
Institute for Land Use + Agricultural Research. 80 pp.
Meijaard, E. & Nijman, V. (2008) Presbytis frontata. The IUCN Red List of Threatened Species 2008:
http://dx.doi.org/10.2305/IUCN.UK.2008.RLTS.T18127A7665520.en. Accessed on 10 February 2019.
Phillipps, Q. & Phillipps, K. (2016). Phillipps' Field Guide to the Mammals of Borneo and their Ecology: Sabah,Sarawak, Brunei and Kalimantan (Second Edition). John Beaufoy Publishing Ltd. 400 pp.
Simanjuntak, W. (2014) Summary Report of Planning and Management of PT Agro Wana Lestari, Kotawaringin
Timur Regency, Central Kalimantan, Indonesia. https://rspo.org. Accessed on 18 February 2019.
van Berkel T.B.T., Rogers, L.D., Kilburn, H.J, Munir, M., Mortiboys, D.M. and Goodchild, R. (2012). A preliminary
biodiversity survey of a lowland rainforest in Bukit Batikap Protection Forest, Central Kalimantan, Indonesian
Borneo. Murung Raya Expedition 2010‐2011 Scientific Report. Heart of Borneo Project.

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