Monkey Species · Southeast Asia
Long-tailed Macaque
The long-tailed or crab-eating macaque (Macaca fascicularis) is a highly adaptable Southeast Asian monkey, at home from mangroves to cities.
By WARN Research & Conservation TeamLast updated
In brief
The long-tailed or crab-eating macaque (Macaca fascicularis) is a highly adaptable Southeast Asian monkey, at home from mangroves to cities. Once considered abundant, it was uplisted to Endangered by the IUCN in 2022 after heavy trapping for the laboratory trade and persecution.
What are the key facts about a Long-tailed Macaque?
The Long-tailed Macaque is a monkey species from Southeast Asia: medium (3–9 kg), adaptable, intelligent, water-loving. The long-tailed or crab-eating macaque (Macaca fascicularis) is a highly adaptable Southeast Asian monkey, at home from mangroves to cities.
| Origin | Southeast Asia |
|---|---|
| Size | Medium (3–9 kg) |
| Typical weight | 3–9 kg; tail as long as the body |
| Lifespan | 15–30 years (wild) |
| Coat & markings | Grey-brown coat with a long tail and a small crest; pale cheeks |
| Temperament | Adaptable, intelligent, water-loving |
| Conservation note | Endangered (IUCN, 2022); CITES Appendix II — heavily trapped for the research trade and persecuted as a pest across its range |
Should you keep a Long-tailed Macaque as a pet?
No. A Long-tailed Macaque is a wild monkey from Southeast Asia, not a companion animal. Private keeping usually means an infant taken from a troop, a lifetime of unmet social needs, and often a legal offence.
People search this page because the Long-tailed Macaque looks small, clever or “manageable” in photos. That is the trap. Wild primates need a troop, a range, and a diet that is not human leftovers. The Long-tailed Macaque is from Southeast Asia; its conservation note on this page is endangered (iucn, 2022); cites appendix ii — heavily trapped for the research trade and persecuted as a pest across its range.
If you met a Long-tailed Macaque in a selfie setting or a roadside stall, walk away and do not pay. Paying creates the next capture. Read this as a species briefing, then use the wildlife guide and the appeals linked at the bottom if you want to help the wild population.
What is a Long-tailed Macaque?
The long-tailed or crab-eating macaque (Macaca fascicularis) is a highly adaptable Southeast Asian monkey, at home from mangroves to cities. Origin is Southeast Asia; coat or markings are described as Grey-brown coat with a long tail and a small crest; pale cheeks.
Treat “species” here as a library label for a wild species or distinct form, not as a kennel-club product.
Where does the Long-tailed Macaque come from?
Long-tailed Macaques come from Southeast Asia. The long-tailed macaque ranges across Southeast Asia — a WARN partner region — swimming readily and foraging on crabs, fruit and human food.
Long seen as a pest and exported in huge numbers for biomedical research, it was reassessed as Endangered in 2022 as trapping, persecution and habitat loss outpaced its adaptability. It also threatens island endemics where introduced.
That origin still shows. A Long-tailed Macaque is medium (3–9 kg) and adaptable, intelligent, water-loving, typically living 15–30 years (wild). Use the history as context for care and conservation, not as folklore to repeat without sources.
What does a Long-tailed Macaque actually need?
A wild Long-tailed Macaque needs the habitat and social system of Southeast Asia, not a spare room. Size (Medium (3–9 kg)) and a adaptable, intelligent, water-loving life history are why private keeping fails.
In the wild that means connected habitat, a diet the species evolved with, and distance from the pet and selfie trades. Captive “care sheets” for wild monkeys are how trafficking gets laundered as husbandry.
If you already work in accredited rescue, follow specialist protocols and licensing. Everyone else: do not acquire a Long-tailed Macaque. Support habitat and anti-trafficking work instead.
What surprises people about the Long-tailed Macaque?
A few details about the breed, alongside the practical care information in this guide.
- It is also called the crab-eating macaque for its shoreline foraging.
- It swims well and will dive for food.
- Despite being adaptable, it was uplisted to Endangered in 2022.
- Some populations use stone tools to crack shellfish.
What health issues should you know about in a Long-tailed Macaque?
Health concerns to discuss with your vet, including changes to watch for and everyday care. This is general guidance, not veterinary advice — always speak to your vet.
Trapping for research and trade
Large-scale trapping for the laboratory and pet trades has driven steep declines in some heavily exploited macaques.
Care: Support enforcement of trade limits and humane, reduced reliance on wild-caught primates.
Human-wildlife conflict
Crop raiding and scavenging near settlements lead to retaliatory killing, trapping, electrocution and vehicle strikes.
Care: Support coexistence programmes, secure waste and crops, and never feed wild troops — feeding worsens conflict.
Habitat loss (wild)
Deforestation for agriculture, logging and development removes the food trees and connected canopy that wild monkeys depend on.
Care: Support habitat protection and deforestation-free supply chains in range countries rather than wildlife tourism that disturbs troops.
Who should skip a Long-tailed Macaque?
Skip a Long-tailed Macaque if you are anyone hoping to keep a Long-tailed Macaque as a pet or photo prop. This Southeast Asia monkey is medium (3–9 kg) and adaptable, intelligent, water-loving — the mismatch is usually lifestyle, not a missing accessory.
This page is allowed to say no. Skip if you are anyone hoping to keep a Long-tailed Macaque as a pet or photo prop. Skip if you are anyone who will pay for a wild-caught or roadside animal. Skip if you are tourists looking for handling or selfies.
A different monkey species on this site may fit. Wanting “a Long-tailed Macaque” after a film or a colour photo is not a reason to ignore the skip list.
What are the hidden catches with a Long-tailed Macaque?
The hidden cost of a Long-tailed Macaque is usually not the purchase price. It is years of care, the health list on this page, and the mismatch between a adaptable, intelligent, water-loving animal and a busy home.
The pet-trade catch
Cute infant Long-tailed Macaques in ads were usually taken from wild families. The adult you cannot house is then dumped, euthanised, or passed on. Do not create that demand.
The tourism catch
Paying to hold, ride, or selfie with a Long-tailed Macaque funds the next capture or a stressed ambassador animal. Distance and accredited viewing are the ethical default.
The trapping for research and trade catch
Large-scale trapping for the laboratory and pet trades has driven steep declines in some heavily exploited macaques. Support enforcement of trade limits and humane, reduced reliance on wild-caught primates.
The human-wildlife conflict catch
Crop raiding and scavenging near settlements lead to retaliatory killing, trapping, electrocution and vehicle strikes. Support coexistence programmes, secure waste and crops, and never feed wild troops — feeding worsens conflict.
How does a Long-tailed Macaque compare with Capuchin Monkey and Rhesus Macaque?
A Long-tailed Macaque is not interchangeable with Capuchin Monkey and Rhesus Macaque. Compare origin, size, lifespan and temperament before you choose — those four lines prevent most regret.
| Monkey fact | Long-tailed Macaque | Capuchin Monkey | Rhesus Macaque |
|---|---|---|---|
| Origin | Southeast Asia | Central & South America | South, Central & Southeast Asia |
| Size | Medium (3–9 kg) | Medium (3–4 kg) | Medium (5–12 kg) |
| Lifespan | 15–30 years (wild) | 15–25 years (wild); up to 40 in protected captivity | 20–30 years (wild); longer in protected settings |
| Temperament | Adaptable, intelligent, water-loving | Curious, dexterous, social | Bold, adaptable, hierarchical |
What is the verdict on the Long-tailed Macaque?
A Long-tailed Macaque is a wild monkey to understand and protect, not a pet to acquire. If you came here to buy one, the verdict is no. If you came here to learn, use the species guide next.
Help looks like habitat, enforcement and refusing the trade — not a cage in a spare room. WARN is a CIC, not a charity; donate only if you want to fund partner work in our network countries, and do not expect Gift Aid.
Monkeys belong in the wild
Monkeys are intelligent, social primates — not pets. The illegal pet trade and habitat loss threaten species from marmosets to macaques. WARN funds anti-trafficking and habitat work for primates in our partner countries.
