# Slow Loris — Facts, Threats & Conservation

*Nycticebus spp. (and Xanthonycticebus pygmaeus, the pygmy slow loris, since 2022)*

> Slow lorises are small nocturnal primates from South and Southeast Asia; every species is threatened with extinction — ranging from Vulnerable to Critically Endangered — largely because of the illegal pet trade, which is fuelled in part by viral social media videos.

**IUCN status:** Threatened (Vulnerable–Critically Endangered)  ·  **WARN range:** Indonesia, Malaysia, Vietnam, Thailand, Cambodia

## Quick facts
| Fact | Value |
| --- | --- |
| Lifespan | Up to ~20 years in human care (pygmy slow loris averages ~17 years); wild lifespan poorly documented |
| Weight | ~265 g (Bornean) to ~2,100 g (Bengal); pygmy slow loris ~120–500 g |
| Head-body length | ~18–38 cm across species (pygmy ~15–25 cm) |
| Diet | Omnivore/exudativore — tree gum and sap, nectar, fruit, insects and small vertebrates |
| Gestation | ~185–197 days (about 6 months) |
| Young per birth | Usually 1; twins common in the pygmy slow loris |
| Sexual maturity | Females ~9 months; males ~18–20 months (pygmy slow loris) |
| Activity | Nocturnal and arboreal; slow, deliberate quadrupedal climbing (no leaping) |
| Distinction | Only venomous primates; brachial-gland secretion activated with saliva |
| CITES | Appendix I (all species, since 2007) |

## Scientific classification
- **Kingdom:** Animalia
- **Phylum:** Chordata
- **Class:** Mammalia
- **Order:** Primates
- **Family:** Lorisidae
- **Genera:** Nycticebus; Xanthonycticebus (pygmy slow loris, since Nekaris & Nijman, 2022)
- **Species:** ~9 slow loris species total (8 Nycticebus + Xanthonycticebus pygmaeus)

## Conservation status
- **Status:** Varies: Vulnerable to Critically Endangered (per species)
- **Population:** No reliable combined global estimate; species assessed individually and surveyed at low densities
- **Trend:** Decreasing for all assessed species
- **Assessed:** Per species (e.g. Javan slow loris assessed Critically Endangered, listed since 2013)
- **CITES:** Appendix I (all slow lorises, uplisted from Appendix II in 2007)
- Only the Javan and Bangka slow lorises are Critically Endangered; others are Endangered (Bengal, Sunda, Sumatran) or Vulnerable (Bornean, Kayan, Philippine).

## Key facts: Slow Loris
- Every slow loris species is threatened with extinction and declining: the Javan and Bangka slow lorises are Critically Endangered, the Bengal, Sunda and Sumatran are Endangered, and the Bornean, Kayan and Philippine are Vulnerable.
- Before being sold as pets, slow lorises routinely have their teeth cut or pulled out with pliers or clippers — without anaesthetic — to prevent their venomous bite.
- Pet-trade mortality is severe across capture, transport and captivity; tooth removal causes infection and stress that many animals do not survive.
- The sight of a "ticklish" slow loris raising its arms in viral videos is actually a fear response — the animal is lifting its arms to access its venom gland.
- Slow lorises cannot be legally traded internationally — all species were uplisted to CITES Appendix I in 2007 — and possession is illegal in most range and import countries.
- Rehabilitation is possible but extremely difficult because of their specialist gum-and-insect diet, nocturnal habits, and the trauma and dental mutilation caused by captivity.

## Why Social Media Is Driving Extinction
Videos of slow lorises being "tickled" or held as pets have accumulated hundreds of millions of views across YouTube, Instagram, and TikTok. Many viewers are unaware that the animal's raised arms represent a fear response to threat, not enjoyment. The videos create demand — people want one. To meet that demand, poachers take wild animals from the forest at night, using torches to freeze them (their eyes reflect the light via a layer called the tapetum lucidum, and sudden brightness disorients them), then cut or pull their teeth out so they cannot bite. Those that survive reach markets in Indonesia, Vietnam, and Thailand. The trafficking networks running these markets have become sophisticated at evading enforcement, and the viral cycle continues.

## The Venom No One Talks About
Slow lorises are unique among primates in producing venom. The venom is formed by combining a secretion from a brachial gland near the elbow with saliva. It is used both for defence and in mother-infant interactions, where mothers coat their young to deter predators. The venom of some species can cause anaphylactic shock in humans — a documented case followed the bite of a wild Kayan slow loris. This is why pet slow lorises have their teeth removed — and why the operation, performed without anaesthetic by traders, is so often fatal. A slow loris without teeth is also unable to feed naturally, further compromising its welfare in captivity.

## What Happens at a Rescue Centre?
Slow lorises confiscated from markets or surrendered by owners arrive with multiple serious problems: dental mutilation, malnutrition, metabolic bone disease from an inadequate diet, severe stress, and sometimes injuries from confinement. Triage involves dental assessment, rehydration, and a carefully controlled reintroduction to natural food — primarily tree gum and sap, nectar, and invertebrates, the exudativore diet they are built for. Animals that cannot be released require lifetime sanctuary care in appropriately sized nocturnal enclosures. Those that recover sufficiently undergo pre-release assessment before soft release into protected forest.

## Taxonomy: One Genus Becomes Two
Slow lorises are strepsirrhine primates — relatives of lemurs and bushbabies, not monkeys. Most were long grouped in the single genus Nycticebus. In 2022 the pygmy slow loris was moved into its own genus, Xanthonycticebus pygmaeus, on the basis of genetic and morphological differences. Counting it, most current sources recognise nine slow loris species in total: eight in Nycticebus plus the pygmy slow loris. All belong to the family Lorisidae and share the same slow, deliberate, non-leaping climbing style and round, forward-facing eyes adapted for night vision.

## Key slow loris species: range and IUCN status
| Species | Scientific name | Main range | IUCN status |
| --- | --- | --- | --- |
| Javan slow loris | Nycticebus javanicus | Java (Indonesia) | Critically Endangered |
| Bangka slow loris | Nycticebus bancanus | Bangka & Borneo (Indonesia) | Critically Endangered |
| Bengal slow loris | Nycticebus bengalensis | India, Bangladesh, mainland SE Asia, S China | Endangered |
| Sunda slow loris | Nycticebus coucang | Sumatra, Malay Peninsula | Endangered |
| Bornean slow loris | Nycticebus borneanus | Borneo | Vulnerable |
| Philippine slow loris | Nycticebus menagensis | Borneo, Philippines | Vulnerable |
| Pygmy slow loris | Xanthonycticebus pygmaeus | Vietnam, Laos, Cambodia, S China | Endangered |

## What WARN does
WARN focuses current slow loris rescue funding on Indonesia and Malaysia, while keeping Vietnam, Thailand and Cambodia context live for education about the wider viral pet-trade crisis.

A rescued slow loris needs months of round-the-clock care — a controlled return to its natural gum-and-insect diet, dental treatment, and a quiet nocturnal enclosure — before it can even be assessed for release. Your gift helps WARN's partners in Indonesia and Malaysia fund that recovery, one loris at a time.

## Frequently asked questions: Slow Loris
### Are slow lorises venomous?
Yes — slow lorises are the only known venomous primates. They produce venom by combining a secretion from a gland near their elbow with saliva. The venom is used for defence and can cause anaphylactic shock in humans, as documented after the bite of a wild Kayan slow loris. This is why slow lorises sold as pets have their teeth removed — an operation performed without anaesthetic that many animals do not survive.

### Why do slow lorises raise their arms?
When a slow loris raises its arms, it is not "enjoying being tickled" — it is accessing its venom gland in preparation for a defensive bite. The behaviour shown in viral videos is a fear response to being handled. The animal's eyes are also often called "cute" when in fact they are wide open because they are being exposed to bright light, which is painful and disorienting for a nocturnal animal.

### Can you keep a slow loris as a pet?
No. All slow loris species were uplisted to CITES Appendix I in 2007, making commercial international trade illegal. National legislation in range countries and in most import countries also prohibits possession. Any slow loris offered for sale has almost certainly been illegally taken from the wild.

### Are all slow loris species critically endangered?
No. Of the recognised slow lorises, only the Javan (Nycticebus javanicus) and Bangka (N. bancanus) are Critically Endangered. The Bengal, Sunda and Sumatran are Endangered, while the Bornean, Kayan and Philippine slow lorises are Vulnerable. Every assessed species is declining, so all are threatened with extinction even though they are not in a single category.

### How many species of slow loris are there?
Eight species are placed in the genus Nycticebus, and the pygmy slow loris was moved to its own genus, Xanthonycticebus, in 2022 — so most current sources recognise nine slow loris species in total.

### What do slow lorises eat?
They are omnivores with a strong reliance on tree gum and sap, which makes them exudativores, supplemented by nectar, fruit, insects and the occasional small vertebrate. This specialist diet is one reason they are so difficult to feed correctly in captivity, and why rescued animals often arrive with metabolic bone disease.

### Can rescued slow lorises be returned to the wild?
It depends on the individual. Animals with intact teeth, rescued young, and not excessively habituated to humans have the best chance. Many animals taken by the pet trade have been held for months or years and have lost critical survival skills. Those that can be released require slow habituation in forest-edge enclosures before any soft-release attempt.

## Sources
- [IUCN Red List — Javan slow loris (Nycticebus javanicus)](https://www.iucnredlist.org/species/39761/179045340)
- [IUCN Red List — search slow loris assessments](https://www.iucnredlist.org/)
- [CITES — Appendices (Nycticebus listed Appendix I)](https://cites.org/eng/app/appendices.php)
- [Wikipedia — Slow loris](https://en.wikipedia.org/wiki/Slow_loris)
- [Wikipedia — Pygmy slow loris (Xanthonycticebus pygmaeus)](https://en.wikipedia.org/wiki/Pygmy_slow_loris)
- [Madani & Nekaris 2014 — Anaphylactic shock from a wild Kayan slow loris bite (PMC4192448)](https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4192448/)
- [New England Primate Conservancy — Javan Slow Loris](https://neprimateconservancy.org/javan-slow-loris/)

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Full guide: https://worldanimalrescuenetwork.org/wildlife-guides/slow-loris