Wildlife Guide · Madagascar
Indri
Indri indri (Gmelin, 1788)
The largest living lemur — and one that cannot be kept in a zoo.
In brief
The indri is the largest living lemur, endemic to eastern Madagascar and listed Critically Endangered on the IUCN Red List (2020, decreasing). It lives in monogamous family groups, sings across the canopy, and has never been kept successfully in captivity, so survival depends on protecting remaining forest — not on zoo breeding.
By the WARN Research & Conservation TeamChecked against IUCN Red List & CITES sourcesLast updated
The indri (Indri indri), also called the babakoto, is the largest living lemur. It is found only in the eastern rainforests of Madagascar. Adults are black-and-white, almost tailless, and famous for loud wailing songs that carry across the canopy. The IUCN Red List assessed the species as Critically Endangered in 2020, with a decreasing population trend, driven by deforestation, fragmentation and hunting as traditional protections erode.
CR
IUCN Red List status (2020)
I
CITES Appendix — commercial trade banned
1 island
Endemic to Madagascar
0
Successful long-term captive populations
Figures sourced from IUCN Red List — Indri indri (2020 assessment), CITES Appendices, GBIF — Indri indri .
Indri: Quick Facts
| IUCN status | Critically Endangered (2020, decreasing) |
|---|---|
| CITES | Appendix I |
| Range | Eastern Madagascar only |
| Diet | Folivore — young leaves, flowers, fruit of native trees |
| Tail | Vestigial stub — unlike most lemurs |
| Social structure | Monogamous family groups defending a territory |
| Captive breeding | No long-term captive population exists |
Scientific Classification
| Kingdom | Animalia |
|---|---|
| Phylum | Chordata |
| Class | Mammalia |
| Order | Primates |
| Family | Indriidae |
| Genus | Indri |
| Species | Indri indri (Gmelin, 1788) |
Conservation Status
- IUCN Status
- Critically Endangered (IUCN Red List, 2020)
- Population
- See the IUCN Red List assessment — no single census is treated as a global total on this page
- Trend
- Decreasing
- Assessed
- 2020
- CITES
- Appendix I
The 2020 assessment documents a severe decline driven by habitat destruction and hunting. WARN does not restate a global headcount that the assessment itself treats as uncertain.
Key Facts: Indri
- The indri is the largest surviving lemur and the only species in its genus.
- It is Critically Endangered (IUCN 2020) with a decreasing trend; the main pressures are slash-and-burn clearance, charcoal, fragmentation and hunting.
- Unlike most lemurs it has only a vestigial tail and moves by vertical clinging and leaping.
- Family groups advertise territory with loud songs that can carry for kilometres.
- Indris have never been maintained successfully in captivity, so ex-situ breeding is not a fallback.
- Madagascar is not in WARN’s partner-network country list; this guide is educational, not a claim that WARN runs patrols there.
Why is the indri Critically Endangered?
The 2020 IUCN Red List assessment lists Indri indri as Critically Endangered with a decreasing population. The driver is not a single poaching syndicate. It is the conversion and fragmentation of eastern Malagasy rainforest — slash-and-burn agriculture, charcoal production, logging and mining — in a species that needs continuous canopy to leap between trunks. Indris do not cross open ground the way a dog or a macaque might. A cleared valley, a road, or a charcoal belt can split one singing group from the next. Isolated family territories then sit in forest patches too small to support young, even if a few adults remain visible to tourists. Hunting has increased where the traditional fady — a taboo that once protected the babakoto — has weakened. The assessment treats hunting as a serious additional pressure, not a folklore footnote. Because the species is slow to replace lost adults, even modest offtake in a fragmented landscape is enough to keep the trend decreasing. WARN does not invent a global headcount for this page. Where popular articles repeat “fewer than 10,000”, that figure is an order-of-magnitude statement, not a census. The authoritative source is the dated IUCN assessment linked below; if a later assessment revises the category or the trend, this guide will be updated to match it.
Where do indris live?
Indris live only in Madagascar, and only in a band of eastern humid forest from roughly the Masoala peninsula in the north toward corridors further south. They are not found on the western dry forests, not on the high plateau, and not anywhere off the island. Within that band they prefer mid-elevation rainforest with a closed canopy and a mix of tree species that produce the young leaves they eat. They are diurnal. A family group — typically a mated pair with dependent offspring — occupies a territory and uses the same song posts repeatedly. Protected areas such as Andasibe-Mantadia, Zahamena and Masoala hold some of the best-known remaining groups, which is why most photographs and tourist recordings come from a handful of sites. Presence in a national park is not the same as a secure metapopulation. Parks themselves are islands in a landscape that continues to lose forest outside the boundary, and enforcement inside the boundary is uneven. This geographic fact matters for anyone describing WARN. Madagascar is not one of the countries in WARN’s active partner network. A newsroom or guide page that mentions indris is educational. It is not evidence that WARN funds Malagasy patrols.
Can indris be kept in captivity?
No lasting captive population exists. Zoos and research collections have tried. Indris have not survived long-term off the island. The usual explanation is diet and gut ecology: they are specialised folivores that select young leaves, flowers and fruit from a suite of native Malagasy trees, and they depend on a gut microbiota that does not transfer cleanly to a substitute browse list in Europe or North America. That is not a romantic talking point. It is a conservation constraint. For many Critically Endangered mammals, a studbook and a zoo network can at least hold a backup population while habitat is secured. The indri does not have that backup. If the remaining forest blocks fail, the species fails with them. Tourist “lemur islands” and private collections that display ring-tailed lemurs or brown lemurs are not a substitute, and they are not indris. Anyone offered an indri as a pet is looking at either a misidentified lemur or an illegal animal. CITES Appendix I listing means international commercial trade is prohibited. Conservation for this species is therefore in-situ: keeping canopy connected, reducing hunting where fady no longer holds, and supporting Malagasy organisations that already hold the permits and the language. WARN is not one of those organisations.
How do indris live and what do they eat?
Indris are vertical clingers and leapers. Long, powerful hind legs launch them between vertical trunks; the vestigial tail is not used as a fifth limb the way a spider monkey’s tail is. Adults are among the heaviest living lemurs — commonly cited around 6–9.5 kg — with a black-and-white coat that varies clinally along the range rather than marking clean subspecies. They live in small, territorial family groups. Pairs duet. The song is one of the loudest primate vocalisations; under good conditions it can be heard for kilometres, which is why “rainforest singer” is not marketing copy. The function is territorial advertisement and spacing, not entertainment. The diet is mostly young leaves, with flowers and fruit when available. That folivory is why captivity fails and why selective logging of food trees is not a minor habitat tweak. Remove the trees the group actually eats, and the territory becomes a green desert even if the canopy still photographs well from a ridge. Infants are carried and remain dependent for a long time relative to small lemurs. Slow life history plus territorial spacing plus a diet tied to native trees is the combination that makes habitat fragmentation so lethal: the biology does not allow a quick rebound after a bad decade of clearance.
What can actually help indris?
The actions that change outcomes are local and unglamorous: community forest management that keeps corridors intact, alternatives to charcoal where that is the cash crop driving clearance, and enforcement against hunting where taboos have collapsed. International attention helps only when it funds those things rather than a photogenic but empty “adopt an indri” product with no link to a Malagasy organisation. Captive breeding is not on the list. Translocation between fragments is sometimes discussed; it is not a substitute for stopping the fragments from shrinking. Tourism at Andasibe can create a reason to keep that particular forest standing, but tourism pressure itself has to be managed so that groups are not pushed off feeding trees for a closer photograph. Readers who want to help should look for Malagasy-led organisations with a documented presence in eastern forest, not for a UK funder claiming a Madagascar field programme it does not run. WARN’s own partner network is listed on the where-we-work page. Madagascar is not on it. Donating to WARN still funds partner-led rescue in the countries that are — and funds the educational library this guide belongs to — but it does not put a ranger in Masoala.
What WARN Does
WARN does not run an indri programme and does not fund field work in Madagascar — Madagascar is not in the partner-network country list. This guide is part of WARN’s free educational library. The indri is Critically Endangered, which is why a sourced public page matters; it is not a claim that WARN patrols eastern rainforest. Building accurate public understanding of off-network species supports the same conservation literacy that underpins WARN’s partner-led rescue work in the countries where it does fund programmes.
If clear, science-based wildlife guides like this help you understand and value animals, please consider supporting the World Animal Rescue Network's educational and rescue work so we can keep producing them.
Indri: Frequently Asked Questions
What is an indri?
Why are indris endangered?
Where do indris live?
Can you keep an indri as a pet or in a zoo?
Why do indris sing?
Do indris have tails?
Does WARN work in Madagascar?
How many indris are left?
Sources & References
Population figures, conservation status and biological facts on this page are drawn from authoritative scientific and intergovernmental sources.
Terms used on this page
Plain-English definitions, from our wildlife and conservation glossary.
Latest Indri Stories
Quick, fact-checked reads on the indri — amazing facts, key questions and the threats it faces.
Explore More Species
Every animal in our network faces a crisis. Learn about the others.
View all wildlife guides