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Original illustration of the Golden Lion Tamarin

Card 19 of 30

Golden Lion Tamarin

Leontopithecus rosalia

Endangered

A third of the wild ones descend from zoo-born monkeys. It worked.

Size
6–10 in + a longer tail · about 1.5 lbs
Lifespan
About 8 years in the wild
Diet
Fruit, insects & small prey
Remaining↑
About 4,800 2023 · per Save the Golden Lion Tamarin
The Golden Lion Tamarin in its habitat, an original illustration
Atlantic Forest of Rio de Janeiro state, Brazil

Where it lives

Atlantic Forest of Rio de Janeiro state, Brazil

Ranges stay general on purpose. Witness never publishes a location that could help someone find an animal already under pressure.

See it on the map

What threatens it

  • Forest cut to 2%
  • Fragmented islands
  • Yellow fever
  • Pet-trade history

Life cycle

Twins are the rule, born fully furred with eyes open. The whole family raises them, the adult male carrying most of all. Females mature at eighteen months, males at two years.

Field study of the Golden Lion Tamarin, an original illustration
Field study · Golden Lion Tamarin
The Golden Lion Tamarin observed in the field, an original illustration
Field observation

Field notes

Every passage carries the number of the source it came from. Nothing here is written from memory.

The golden lion tamarin is a monkey small enough to hold, crowned with a backswept golden mane like a miniature lion's.Source 1

Families of two to eight sleep from dusk to sunrise in tree holes, tucked together for warmth.Source 1

Mothers usually bear twins — rare among primates — and the adult male does the largest share of the carrying.Source 1

Its Atlantic Forest home has been cut to two percent of its original area, scattered into islands of green.Source 2

By the 1960s, fewer than two hundred remained.Source 2

So zoos rebuilt the species: between 1984 and 2001, 146 tamarins born in 43 institutions on three continents went home to Brazil.Source 3

It worked. About a third of wild golden lion tamarins today descend from animals raised in human care.Source 1

The forest is being resewn too: restored pastures, corridor plantings, and a forested overpass that carries tamarins across a highway.Source 4Source 5

When yellow fever killed a third of the species, conservationists answered by vaccinating wild monkeys — over five hundred so far.Source 6Source 4

To witness the golden lion tamarin is to see what patience across generations can rebuild: roughly 4,800 now leap through the canopy.Source 4

The Golden Lion Tamarin drawn to scale beside a human figure
Scale study · beside a human figure

Did you know

The 146-tamarin reintroduction, drawing on 43 institutions in eight countries, has been called perhaps the most collaborative conservation effort in history.

This week’s act · for the Golden Lion Tamarin

Read the rebuilding story

Read the Smithsonian's golden lion tamarin profile: the 1970s rescue plan, the reintroductions, and the forest being stitched back together.

with Smithsonian's National Zoo

6 minutes · Worldwide · verified 24 August 2026

Witness records that this door was opened. It never claims the outcome.

Help & protection

  • Save the Golden Lion Tamarin

    Grow Trees for GLTs

    Local farmers grow native seedlings that are planted as forest corridors reconnecting the fragments tamarins live in.

    View initiative ↗Verified 24 August 2026
  • Smithsonian's National Zoo

    GLT Conservation Program

    The Smithsonian-founded program behind the captive breeding and reintroduction, still active in research, education, and habitat restoration.

    View initiative ↗Verified 24 August 2026

Sources & verification

Status
Endangered
Range (generalized)
Atlantic Forest of Rio de Janeiro state, Brazil
Fact-checked
25 August 2026
Location review
generalized
Artwork
AI-assisted stylized illustration
  1. Smithsonian's National Zoo & Conservation Biology Institute

    Golden lion tamarin

    Open source ↗Last accessed 24 August 2026
  2. Save the Golden Lion Tamarin

    About GLTs

    Open source ↗Last accessed 24 August 2026
  3. Save the Golden Lion Tamarin

    Reintroduction

    Open source ↗Last accessed 24 August 2026
  4. Save the Golden Lion Tamarin

    Save the Golden Lion Tamarin

    Open source ↗Last accessed 24 August 2026
  5. Save the Golden Lion Tamarin

    GLT Corridor Connection

    Open source ↗Last accessed 24 August 2026
  6. Save the Golden Lion Tamarin

    Yellow fever vaccination of wild golden lion tamarins

    Open source ↗Last accessed 24 August 2026
  7. Save the Golden Lion Tamarin

    Grow Trees for GLTs

    Open source ↗Last accessed 24 August 2026

Record last fact-checked 25 August 2026. The illustrations are original, drawn for Witness; they are not photographs.

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