Nycticebus bengalensis
Silhouette: Mareike C. Janiak · PhyloPic
In 3 days ~30% in a week ~60%
The Bengal slow loris (Nycticebus bengalensis) or northern slow loris is a strepsirrhine primate and a species of slow loris native to the Bangladesh, Northeast India, Cambodia, Laos, Burma, Vietnam, southern China, and Thailand. Its geographic range is larger than that of any other slow loris species. Considered a subspecies of the Sunda slow loris (N. coucang) until 2001, phylogenetic analysis suggests that the Bengal slow loris is most closely related to the Sunda slow loris. However, some individuals in both species have mitochondrial DNA sequences that resemble those of the other species, due to introgressive hybridization. It is the largest species of slow loris, measuring 26 to 38 cm (10 to 15 in) from head to tail and weighing between 1 and 2.1 kg (2.2 and 4.6 lb). Like other slow lorises, it has a wet nose (rhinarium), a round head, flat face, large eyes, small ears, a vestigial tail, and dense, woolly fur. The toxin it secretes from its brachial gland (a scent gland in its arm) differs chemically from that of other slow loris species and may be used to communicate information about sex, age, health, and social status.
The Bengal slow loris is nocturnal and arboreal, occurring in both evergreen and deciduous forests. It prefers rainforests with dense canopies, and its presence in its native habitat indicates a healthy ecosystem. It is a seed disperser and pollinator, as well as a prey item for carnivores. Its diet primarily consists of fruit, but also includes insects, tree gum, snails, and small vertebrates. In winter, it relies on plant exudates, such as sap and tree gum. The species lives in small family groups, marks its territory with urine, and sleeps during the day by curling up in dense vegetation or in tree holes. It is not a seasonal breeder, reproducing once every 12–18 months and usually giving birth to a single offspring. For the first three months, mothers carry their offspring, which reach sexual maturity at around 20 months. The Bengal slow loris can live up to 20 years.
The species is listed as endangered on the IUCN Red List, and is threatened with extinction due to growing demand in the exotic pet trade and traditional medicine. It is one of the most common animals sold in local animal markets. In traditional medicine, it is primarily used by wealthy to middle-class, urban women following childbirth, but also to treat stomach problems, broken bones, and sexually transmitted diseases. It is also hunted for food and suffers from habitat loss. Wikipedia →
| # | Park | Country | Daily sighting probability |
|---|---|---|---|
| 1 | Khao Yai National Park | 🇹🇭 Thailand | |
| 2 | Kaeng Krachan National Park | 🇹🇭 Thailand |
| # | Zoo / Centre | Country | |
|---|---|---|---|
| 1 | Aquarium featuring native freshwater species from the Mekong River | 🇨🇳 China | |
| 2 | Wild Elephant Valley | 🇨🇳 China |
With luck
About 10% of wildlife watchers report a Bengal Slow Loris sighting in Kaeng Krachan National Park on a given day, based on 19 verified sightings from GBIF citizen-science data from 2019 to 2026. It is the 19th most-seen of the 32 mammals we can rate there. Over three days the chance rises to about 30%, and over a week to about 60%, if each day is a fresh chance.
August
In that month about 30% of wildlife watchers report a Bengal Slow Loris in Kaeng Krachan National Park on a given day, against under 5% in January, July and September, the lowest months. That is one of Kaeng Krachan National Park's wettest months, with about 200 mm of rain against 30 mm in December.
Between 2 and 5 pm
Across all the parks we cover, that three-hour window holds the most Bengal Slow Loris sightings with a recorded time, and about 8 in 10 of them come between 6 am and 6 pm: it is a daytime animal.
2nd of 2
Of the 2 parks where we can rate Bengal Slow Loris sightings, Kaeng Krachan National Park ranks 2nd at about 10%. The best odds are in Khao Yai National Park (Thailand, about 20%).
Same order: Primates
The closest relatives of the Bengal Slow Loris that you can see in Kaeng Krachan National Park (order Primates) are Dusky Leaf-monkey (about 70%), Lar Gibbon (about 50%) and Stump-tailed Macaque (about 40%), with each one's daily chance of a sighting.
GBIF citizen-science records
It is estimated from how often the Bengal Slow Loris is recorded against all the mammals logged in Kaeng Krachan National Park (19 verified sightings from 2019 to 2026), calibrated against known sighting rates. Figures are rounded to the nearest 10% because citizen-science data supports honest approximations, not decimals, and months with records from fewer than five people show "—". How it works.
