SEAVR 2019: 076‐083
ISSN: 2424‐8525
Date of publication: 03 December 2019
Hosted online by ecologyasia.com

Primate sightings in Sangkulirang‐Mangkalihat Karst,
East Kalimantan, Indonesia
Ika Yuni AGUSTIN, Eni HIDAYATI, Nur RAHMAN, Arif SETIAWAN
ikayuni.agustin@gmail.com (AGUSTIN), enihidayati@gmail.com (HIDAYATI)SUMMARY
The Sangkulirang‐Mangkalihat Karst is an area in Kutai Timur and Berau regencies of East Kalimantan province,
Indonesia, on the island of Borneo. The peninsula is dominated by limestone geology, and it covers an area of over
18,000 square kilometres.
Brief primate surveys were conducted in karst areas in seven locations spanning from Sangkulirang to Mangkalihat.
A total of nine primate species were found. Diurnal surveys were made in Suaran (5 days), Karangan Dalam (5 days),
Tepian Langsat (Marang) (5 days), Biatan Ulu (4 days), Lobang Kelatak (5 days), Lobang Belanda (Teluk Sulaiman) (3days) and Danau Sigending (Teluk Sulaiman) (2 days). Night surveys were also carried out to observe nocturnal
primates. This activity was part of the TFCA Kalimantan Project, led and managed by the Karst Research Group ofthe Faculty of Geography, Gadjah Mada University. A total of nine species of primate were seen: Nycticebus sp.,
Cephalopachus bancanus, Macaca fascicularis, Macaca nemestrina, Presbytis canicrus, Presbytis rubicunda, Nasalis
larvatus, Hylobates funereus and Pongo pygmaeus.

1. Slow Loris
Identity of subjects: Nycticebus sp. (Mammalia: Primates: Lorisidae).
Observers: Ika Y. Agustin, Nur Rachman, Nuhoni Prastya, Betty Miliyanawati, A. Syarif, Burhanudin.
Photographs by: Nur Rachman (Fig. 1), Burhanudin (Fig. 2).
Subjects identified by: Wirdateti, Arif Setiawan.
Location: Lobang Kelatak, Berau, East Kalimantan, Indonesia.
Habitat: Karst forest.
Date and time: 01 November 2016, 20:09 hrs (Fig. 1), 02 November 2016, 20:20 hrs (Fig. 2).
Description of records: A slow loris was seen on a tree adjacent to a logging road, moving slowly on branches
around 4 meters from the ground (Fig. 1). The next day two slow loris were sighted inside the karst forest sitting
on a tree, around 0.5 kilometers from the logging road, one of which was photographed (Fig. 2). A total of three
individuals of slow loris were seen in Lobang Kelatak, and we also saw one captive slow loris kept as a pet in thenearby village of Biatan Ulu.
Remarks: The slow lorises are tentatively identified as Nycticebus kayan, based on their dark and highly
contrasting face mask, and their eyes which are surrounded with dark patches (Munds et al., 2013). There is still no
information about the protection status of Nycticebus kayan in IUCN nor CITES, and the range distribution for thisspecies is also not mapped and studied (Widarteti, pers. comm., July 9, 2019).

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Fig. 1.

Fig. 2.

2. Western Tarsier / Horsfield’s Tarsier
Identity of subject: Cephalopachus bancanus (Mammalia: Primates: Tarsiidae).
Observers: Ika Y. Agustin, Nur Rachman.
Photograph by: Ika Y. Agustin.
Subject identified by: Ika Y. Agustin, Nur Rachman.
Location: Suaran, Berau, East Kalimantan, Indonesia.
Habitat: Karst forest.
Date and time: 07 August 2016, 21:11 hrs.
Description of record: Cephalopachus bancanus was documented during a night survey: two were seen while theycaught insects, one of which was about 7 meters from our observation point on a tree around 1.5 meters from theground (Fig. 3).
Remarks: This nocturnal primate was identified basedon its small body size, big eyes and the long tail withhairs on the tip. IUCN categorise this species asVulnerable. Habitat loss is the main threat for thisprimate.
Our local guide in Suaran explained that this primate
can be found in rocky hills and sometimes in caves in
the Suaran forest. The guide also said that the tarsiers
usually prey on cockroaches, grasshoppers or otherinsects in caves. Based on the information from ourlocal guide in Biatan Ulu, this primate also exists in theBiatan Ulu forest. The guide also told us thatsometimes dead tarsiers are found in oil palm
plantations, having died because they digested insects
contaminated with pesticides or fertilizers from the oilpalm plantation. This species is commonly seen inlowland areas, but in 1998 it was recorded at a highelevation (1200 metres) in West Kalimantan (Gorog &Sinaga, 2008).

Fig. 3.

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3. Long‐tailed Macaque
Identity of subjects: Macaca fascicularis (Mammalia: Primates: Cercopithecidae).
Observers: Ika Y. Agustin, Nur Rachman, Nuhoni Prastya, Betty Miliyanawati, A. Syarif, Burhanudin.
Photograph by: A. Syarif.
Subjects identified by: Ika Y. Agustin, Nur Rachman, Betty Miliyanawati.
Location: Biatan Ulu, Berau, East Kalimantan, Indonesia.
Habitat: Karst forest.
Date and time: 21 October 2016, 14:31 hrs.
Description of record: A group of around 20 Long –tailed Macaque was observed in karst forest adjacent tofarmland. Other individuals were observed eating cassava and banana in the farmland. Images were taken of an
infant clinging to its mother, and another female (Fig. 4).
Remarks: This primate was present in all seven study
sites. During the survey, groups of macaques werefound in karst forest, riverine areas, mangrove forest
and lowland forest.
Meijaard &Nijman (2003) stated that the habitat ofLong‐tailed Macaque is more varied than the Pig‐
tailed Macaque: they can be found in peat swamp
forest, mangrove forest, freshwater swamp, tropicalevergreen forest as well as riverine forest.

Fig. 44. Southern Pig‐tailed Macaque
Identity of subjects: Macaca nemestrina (Mammalia: Primates: Cercopithecidae).
Observers: Ika Y. Agustin, Nur Rachman, Nuhoni Prastya, Betty Miliyanawati, A. Syarif, Burhanudin.
Photograph by: Ika Y. Agustin.
Subject identified by: Ika Y. Agustin, Betty Miliyanawati.
Location: Lobang Kelatak, Berau, East Kalimantan, Indonesia.
Habitat: Karst forest.
Date and time: 31 October 2016, 05:41 hrs.
Description of record: Two adult Southern Pig‐tailed Macaque were documented foraging in a tree, at a height ofaround 10 meters, and around 20 meters from the observers. One was photographed (Fig. 5).
Remarks: The Southern Pig‐tailed Macaque wasidentified based on its yellow‐brown fur and its shorttail. The macaques were spotted in Biatan Ulu andLobang Kelatak. The observers also found the monkey
being kept as pets by villagers in the nearby village ofSuaran. The observers did not find this species in karst
forest. Commonly, this macaque can be found inlowlands and hills of Borneo in various habitats suchas peat swamp forest, tropical wet evergreen forest
and tropical mountain evergreen forest (Meijaard&Nijman, 2003).
Fig. 5.

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5. Miller’s Grizzled Langur (or Kutai Grey Langur)
Identity of subjects: Presbytis canicrus (Mammalia: Primates: Cercopithecidae).
Observers: Ika Y. Agustin, Nur Rachman, Nuhoni Prastya, Betty Miliyanawati, A. Syarif Burhanudin.
Photographs by: Nur Rachman.
Subjects identified by: Ika Y. Agustin, Nur Rachman, Arif Setiawan.
Location: Lobang Kelatak, Berau, East Kalimantan, Indonesia.
Habitat: Karst forest.
Date and time: 01 November 2016, 09:16 hrs.
Description of record: The observers were walking along a logging road when suddenly around 15 individuals ofMiller’s Grizzled Langur, which were active in the trees, fled deeper into the forest. One individual was photographedon the branch of a tree, around 15 metres away, and at a height of around 15 meters, eating a fruit (Figs. 6 and 7):
it was observed for 7 minutes before it too fled deeper into the forest.
Remarks: This least known Bornean leaf‐eating monkey was identified based on the distinctive darker fur on its headcompared with its body. Its frontal colour is white, while the dorsal fur is grey. IUCN categorise this primate as
Endangered: habitat loss and hunting are the main threats to this species. Their precise geographical range is still
uncertain.
During a survey of the species in East Kalimantan, conducted by Setiawan et al. (2009), the team only found one
group on the banks of Baai River, and they concluded that this primate is facing local extinction in Kutai National
Park. Lhota et al. (2012) discovered 11 individuals in Wehea forest, East Kutai. The local guide informed the observersthat the species, whose local name is Buhangat/Berangat, also exists in Karangan Dalam forest but is very rare.
Furthermore, the guide informed the observers that the langur is valuable for Chinese medicine.
P. canicrus was formerly considered to be a subspecies of P. hosei but is now widely treated as a distinct species(Roos et al, 2014).

Fig. 6.

Fig. 7.

6. Maroon Langur
Identity of subjects: Presbytis rubicunda (Mammalia: Primates: Cercopithecidae).
Observers: Ika Y. Agustin, Nur Rachman, Nuhoni Prastya, Betty Miliyanawati, A. Syarif, Burhanudin.
Photographs by: Ika Y. Agustin.
Subject identified by: Ika Y. Agustin, Nur Rachman, Betty Miliyanawati.
Location: Lobang Kelatak, Berau, East Kalimantan, Indonesia.
Habitat: Karst forest.
Date and time: 31 October 2016, 06:57 hrs.
Description of record: A group of 8 Maroon Langur were observed foraging in a tree with dense canopy around 20
meters from the ground. Clear pictures were taken of one individual (Figs. 8 and 9).

79Remarks: The Maroon Langur was identified based on its maroon fur colour. The common threat faced by thisspecies is hunting for meat and traditional medicine. In addition, habitat loss due to deforestation also threatens thespecies. IUCN categorise the species as Least Concern.
We encountered this primate in Suaran, Karangan Dalam, Marang, Lobang Kelatak and Teluk Sulaiman, but we did
not locate it in Biatan Ulu possibly due to persistent heavy rain in the area at the time of the survey (based on ourlocal guides’ explanation, however, the primate does occur in the Biatan Ulu forest). This langur has the widest
distribution range on Borneo. It occurs in a wide range of habitat types such as peat swamp forest, tropical wet
evergreen forest, tropical montane evergreen forest and riverine forest (Meijaard & Nijman, 2003). According toIUCN (2019) the primate is found in at least 10 protected areas including Kutai National Park and Sungai Wain
Protection Forest in East Kalimantan. There is still little information about the primate’s distribution in other areas,including in karst forest in East Kalimantan.

Fig. 8.

Fig. 9.

7. Bekantan / Proboscis Monkey
Identity of subjects: Nasalis larvatus (Mammalia: Primates: Cercopithecidae).
Observers: Ika Y. Agustin, Nur Rachman, Nuhoni Prastya, Betty Miliyanawati, A. Syarif, Burhanudin.
Photographs by: Ika Y. Agustin.
Subjects identified by: Ika Y. Agustin, Nur Rachman, A. Syarif.
Location: Danau Sigending, Teluk Sulaiman, East Kalimantan, Indonesia.
Habitat: Coastal karst forest.
Date and time: 12 November 2016, 11:36‐12:00 hrs.
Description of record: Two groups of Bekantan were seen. The first group was spotted on a logging road, clearly
intending to go to the mangrove forest across the road. One juvenile in the group was photographed (Fig. 10), andalso an adult male (Fig. 11). We encountered a second group around 500 metres from the first group: they also
intended to cross the road as some individuals were still on the ground and some were hiding behind the tree
canopy.
Remarks: The Bekantan were identified based on their distinctive long nose and orange fur. The presence of thespecies in Danau Sigending area is known by the local people and tourists (the monkeys’ activities in the mangrove
forest is one of the tourist attractions there). A review of species distribution showed that this Bornean endemic
occurs throughout coastal Kalimantan, and up to the headwaters of probably all major rivers. In East Kalimantan, its
distribution includes Sangkulirang (Meijaard &Nijman, 2000).

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Fig. 10.

Fig. 11.

8. Northern Gray Gibbon (or ‘North Borneo Gibbon’)Identity of subjects: Hylobates funereus (Mammalia: Primates: Hylobatidae).
Observers: Ika Y. Agustin, Nur Rachman, Nuhoni Prastya, Betty Miliyanawati, A. Syarif, Burhanudin.
Photographs by: Ika Y. Agustin.
Subjects identified by: Quentin Phillipps, Arif Setiawan.
Locations: Karangan Dalam, Berau, Lobang Kelatak and Berau, East Kalimantan, Indonesia.
Habitat: Karst forest.
Date and time: 16 August 2016, 14:00 hrs (Fig. 12), 11 November 2016, 08:30 hrs (Fig. 13).
Description of record: An adult female and a juvenile Hylobates funereus were sighted on a tree near Karangan
Dalam: once they were aware of the observers’ presence they fled to another tree (Fig. 12). In a separate sighting
at Lobang Kelatak, an adult Hylobates funereus was seen hanging by its arms from a tree, at a distance of around
12 meters from our observation point (Fig. 13).
Remarks: The gibbon was identified as Hylobates funereus based on their locality. This gibbon is distributed in
Kalimantan (North), Sabah, Sarawak and Brunei (Cheyne et al, 2016). It was spotted in 5 study locations (i.e. Suaran,Karangan Dalam, Biatan Ulu, Lobang Kelatak and Teluk Sulaiman) through direct sighting and by hearing their loudcall. It was not recorded in Marang: a massive forest fire had previously occurred in the karst forest and now theforest is dominated by Macaranga spp. that have relatively low height and smaller canopy cover. Cheyne et al. (2016)
revealed that gibbon density is strongly correlated with canopy cover and tree height.
The presence of Hylobates funereus in the forest around the karst in East Kalimantan has been recorded during a
biodiversity survey in the Sangkulirang Peninsula by Salas et al. (2005). Setiawan et al (2009) reported it fromSakulirang river, Baai River and northeast of Mt. Beriunit. It was also found in Beriun forest during a biodiversity
survey in 2011 (Kusrini & Bukhori, 2011).

Fig. 12.

Fig. 13.

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9. Northeast Bornean Orangutan
Identity of subject: Pongo pygmaeus morio (Mammalia: Primates: Hominidae).
Observers: Ika Y. Agustin, Nur Rachman, Nuhoni Prastya, Betty Miliyanawati, A. Syarif, Burhanudin.
Photographs by: Burhanudin (Fig.14), Ika Y. Agustin (Fig.15).
Subjects identified by: Ika Y. Agustin, Nur Rachman, Betty Miliyanawati, Arif Setiawan.
Locations: Karangan Dalam, Berau and Tepian Langsat (Marang), East Kalimantan, Indonesia.
Habitat: Karst forest.
Date and time: 15 August 2016, 14:00 hrs (Fig. 14), 23 August 2016, 07:16 hrs (Fig. 15).
Description of record: At Karangan Dalam an adult male Northeast Bornean Orangutan (Pongo pygmaeus morio)
was sighted sitting on his nest up in a tree around 6 meters from the ground (Fig.14). At Tepian Langsat an adult
was seen eating tree bark of Melicope sp. around 9 metres up in a tree (Fig, 15): once aware of the observers’
presence it tried to conceal itself behind the tree trunk. After a photograph was taken, the observers left theorangutan to avoid further disturbing it.
Remarks: There are three subspecies of orangutan in Borneo: Pongo pygmaeus morio, Pongo pygmaeus pygmaeus
and Pongo pygmaeus wurmbii. We categorise these 2 individuals as Northeast Bornean Orangutan (Pongo pygmaeusmorio) based on the range description in IUCN red list (IUCN, 2019). The Northeast Bornean Orangutan occur inSabah, Sarawak, North Kalimantan and East Kalimantan (IUCN, 2019). The species is listed as Critically Endangeredby IUCN.
The two individuals of orangutan were found in disturbed forest near ex‐logging roads. In both areas, the observers
also spotted more than 25 orangutans’ nests up in the trees. In Marang their leftovers, such as bark and lianas, werealso found scattered on the forest floor. The occurrence of this species in Marang karst forest has been reported
before by Marshall et al. (2007) through an orangutan nest survey. The existence of this ape in other karst forest in
East Kalimantan, such as in Beriun, has been reported in previous surveys by Kusrini & Bukhori (2011).

Fig. 14.

Fig. 15.

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