Quick answer
IUCN status: EndangeredProboscis monkey at a glance
The proboscis monkey (Nasalis larvatus) is a mammal in the family Cercopithecidae. Range in Indonesia: Kalimantan (Indonesian Borneo). Diet: leaves, selected fruits, and seeds; a herbivore. IUCN Red List status: Endangered. It is a legally protected species in Indonesia (Regulation P.106/2018).
| Scientific name | Nasalis larvatus |
|---|---|
| Indonesian name | Bekantan |
| Group | Mammals |
| Family | Cercopithecidae |
| Range in Indonesia | Kalimantan (Indonesian Borneo) |
| Linked habitats | Mangroves, Freshwater Wetlands, Tropical Rainforests |
| Native range | Borneo |
| Diet | Leaves, selected fruits, and seeds |
| Ability | Climbing and swimming |
| IUCN status | Endangered · Mandai Wildlife Reserve — Proboscis monkey |
| Legal protection in Indonesia | Protected · Regulation P.106/2018 · annex no. 18 |
| Body weight | Males about 20 kg; females about half that · Wisconsin National Primate Research Center — Proboscis monkey |
| Nose length | An adult male's nose can exceed 10 cm · Wisconsin National Primate Research Center — Proboscis monkey |
| Swimming | Can swim up to 20 m fully submerged · Wisconsin National Primate Research Center — Proboscis monkey |
| Diet type | Herbivore (plant-eater) — leaf and fruit/seed eater (folivore-frugivore) · Animal Diversity Web |
| Reproduction | Giving birth to live young (viviparous) · Animal Diversity Web |
| Observance days | Indonesian Primate Day (30 January) |
| Active | Diurnal (active by day) — The research synthesis describes feeding, travelling and resting during daylight, with feeding peaks in the morning and at dusk. · Wisconsin National Primate Research Center — Proboscis monkey ecology |
In this guide (12)
A distinctive Bornean primate
Proboscis monkeys are native to Borneo, including Indonesian Kalimantan. Adult males have much larger noses than females. Consider body colour, proportions, and behaviour together when identifying wildlife; not every monkey seen in mangroves is a proboscis monkey. Use photographs taken at a respectful distance for learning.
Evidence: Wisconsin National Primate Research Center — Proboscis monkey ↗
Forests beside water
Riverine forests, swamps, and mangroves provide feeding, movement, and resting places. These monkeys can swim, but that ability does not make tree loss unimportant. Riverbank protection needs to retain vegetation cover and connectivity rather than simply leaving a narrow line of trees beside the water.
Evidence: Wisconsin National Primate Research Center — Proboscis monkey ↗ · Mandai Wildlife Reserve — Proboscis monkey ↗
Specialised digestion
Proboscis monkeys eat leaves and selected fruits and seeds. Microorganisms in their digestive system help process plant material. These needs differ from the assumption that all monkeys can be offered human food. Avoid feeding wildlife during river trips; observation need not alter an animal’s natural food choices.
Groups and resting places
Research describes groups often containing an adult male, females, and young, alongside other group structures. Sleeping trees near rivers are important in daily routines. PanduanHewan recommends keeping boats from crowding beneath sleeping trees; leave space and limit disturbance. Visible groups should not be treated as a performance for visitors.
Evidence: Wisconsin National Primate Research Center — Proboscis monkey ↗
Fragmentation is more than lost area
A northwestern Sabah field study published online in 2025 found scattered proboscis monkey populations with poor habitat connectivity. These Malaysian findings are not a count of Kalimantan monkeys, but illustrate why forest extent and connections need to be examined together. When reading a survey, distinguish its study area, habitat type, and uncertainty rather than extending the result to the whole island.
Evidence: Bernard et al. — Proboscis monkey population and habitat in northwestern Sabah (2025/2026) ↗
River visits that support habitat
As a precaution, PanduanHewan recommends operators who explain viewing distances, waste management, and benefits for nearby communities. Decline offers to touch or feed monkeys. Learn about mangroves and wetlands to understand their dependence on functioning landscapes; planting one tree does not immediately replace a lost forest or restore its connections.
Evidence: Bernard et al. — Proboscis monkey population and habitat in northwestern Sabah (2025/2026) ↗ · Mandai Wildlife Reserve — Proboscis monkey ↗
Explore related habitats
These habitat relationships are supported by species sources in this guide. This is not a complete range map.
Scientific classification of the Proboscis monkey
| Kingdom | Animalia |
|---|---|
| Phylum | Chordata |
| Class | Mammalia |
| Order | Primates |
| Family | Cercopithecidae |
| Genus | Nasalis |
| Species | Nasalis larvatus |
Source: GBIF Backbone Taxonomy, adjusted to the ranks commonly used in school biology (for example class Reptilia).
Common questions about the proboscis monkey
What is the scientific name of the proboscis monkey?
The scientific name of the proboscis monkey is Nasalis larvatus, in the family Cercopithecidae. In Indonesian it is called Bekantan.
What kind of animal is the proboscis monkey?
The proboscis monkey is a mammal in the family Cercopithecidae. By diet it is a herbivore (plant-eater): a leaf and fruit/seed eater (folivore-frugivore).
Where does the proboscis monkey live in Indonesia?
In Indonesia, this guide records the proboscis monkey in: Kalimantan (Indonesian Borneo).
Source-supported habitats: Mangroves, Freshwater Wetlands, Tropical Rainforests.
What does the proboscis monkey eat?
Diet of the proboscis monkey: leaves, selected fruits, and seeds. That makes it a herbivore (plant-eater). Source: Animal Diversity Web.
How does the proboscis monkey reproduce?
The proboscis monkey reproduces by giving birth to live young (viviparous). Source: Animal Diversity Web.
Is the proboscis monkey nocturnal?
The cited source records the proboscis monkey as diurnal (active by day). The research synthesis describes feeding, travelling and resting during daylight, with feeding peaks in the morning and at dusk. Source: Wisconsin National Primate Research Center — Proboscis monkey ecology.
See also the list of nocturnal and diurnal animals in Indonesia.
What are the main features of the proboscis monkey?
Key features of the proboscis monkey, from this guide’s sources: Body weight: Males about 20 kg; females about half that.
How big is the proboscis monkey?
Body weight: Males about 20 kg; females about half that. Source: Wisconsin National Primate Research Center — Proboscis monkey.
What is the scientific classification of the proboscis monkey?
Scientific classification of the proboscis monkey: kingdom Animalia, phylum Chordata, class Mammalia, order Primates, family Cercopithecidae, genus Nasalis, species Nasalis larvatus.
Source: GBIF Backbone Taxonomy, adjusted to the ranks commonly used in school biology.
Is the proboscis monkey endangered?
Yes. The global conservation status of the proboscis monkey: Endangered. In the IUCN system, this category means it is considered to face a very high risk of extinction in the wild. Source: Mandai Wildlife Reserve — Proboscis monkey.
This global category is separate from national legal protection. Is the proboscis monkey protected in Indonesia?
Is the proboscis monkey protected in Indonesia?
Yes. The proboscis monkey (Nasalis larvatus) is a protected species in Indonesia under Environment and Forestry Ministerial Regulation No. P.106/MENLHK/SETJEN/KUM.1/12/2018 on protected plant and animal species (annex, entry 18).
Article 21(2) of Law No. 5 of 1990, as amended by Law No. 32 of 2024, prohibits anyone from hunting, catching, injuring, killing, storing, owning, keeping, transporting or trading a protected animal, alive or dead, including its body parts, eggs and nests.
If you see this animal being traded, kept or injured, contact the local BKSDA office.
Can the proboscis monkey be kept as a pet?
No. Because the proboscis monkey is a protected species, catching, owning, keeping, transporting or trading it without a permit is prohibited by law. Trading without a permit through electronic media is also prohibited.
If you see this animal for sale or being kept, report it to the local BKSDA office.
Sources & references
- Wisconsin National Primate Research Center — Proboscis monkey ↗
- Mandai Wildlife Reserve — Proboscis monkey ↗
- Bernard et al. — Proboscis monkey population and habitat in northwestern Sabah (2025/2026) ↗
- Peraturan Menteri LHK Nomor P.106/MENLHK/SETJEN/KUM.1/12/2018 tentang Jenis Tumbuhan dan Satwa yang Dilindungi ↗
- Animal Diversity Web ↗
- Animal Diversity Web ↗
- GBIF Backbone Taxonomy (GBIF) ↗
References can change. Check dates and context in the original source. How we use sources and data →
National parks where it is recorded
According to the official national park profiles from the KSDAE directorate. The animal may also live elsewhere.
Related causes and news
Further reading
Proboscis monkey: facts, threats and conservation ↗ — World Animal Rescue Network.
Related site: PanduanHewan’s founder is also a director of World Animal Rescue Network.
Cite this page
Credit PanduanHewan when referring to this page. Check the original evidence sources before reusing a claim.
PanduanHewan. Proboscis monkey (Nasalis larvatus). Last substantive update: 7 October 2026. https://panduanhewan.org/en/species/proboscis-monkey/