Thirty-five years ago today, eight golden lion tamarins were reintroduced to the wild at the Reserva Biológica de Poço das Antas in Brazil. They had been born in zoos in the United States and learned to forage in “free-range” habitats before making the long journey back to their ancestral homeland.
In 1972, golden lion tamarins were facing extinction. It was estimated that there were only about 200 individuals left in the wild, and captive birth rates were low. Research zoologist Dr. Devra Kleiman, a recent hire at the National Zoological Park, established the Golden Lion Tamarin Conservation Program, which ultimately became a partnership of many conservation organizations and zoos.
The first goal was to increase the captive birth rate. Through research and experimentation, the researchers found that changes in diet, specifically additional protein, greatly increased the number of births. By the early 1980s, there were more golden lion tamarins in captivity than necessary to support the breeding population. Reintroduction to the wild was the second goal.
Captive animals cannot simply be let loose in the wild. They need to learn to forage and protect themselves. Many golden lion tamarins were moved from indoor enclosures to “free-range” habitats—larger outdoor areas with natural vegetation, insects, birds, and other animals. They were still provided with food, but it was often hidden in order to teach them to forage. Shelter would often be a nest box designed to mimic a hole in a tree.
In November 1983, fifteen golden lion tamarins were carefully crated and shipped to Brazil. Upon arrival, they were quarantined, where one tamarin gave birth to twins. On May 2, 1984, nine of the golden lion tamarins were moved to a large temporary enclosure that had been erected within the forest itself. A wild golden lion tamarin, found in a patch of forest too small to sustain the animal, was also introduced to this enclosure. Twelve weeks later, on July 25, eight of the golden lion tamarins were released from the area.
After reintroduction, the animals were closely monitored by both American scientists and trained locals. The free-range habitats had not prepared them to survive in the wild. Several died and food and other essentials had to be provided to many others. The effort was not a total loss though. Two females gave birth in the wild and the young adapted quite well, quickly becoming self-sufficient.
Reintroduction efforts continued with the release of a new group of captive-born golden lion tamarins each year. Survival rates increased and each successive generation gave birth to their own young. Efforts have also been made to protect and expand their habitats. Today, there are approximately 3,200 golden lion tamarins living in the wild, about one-third of which are descendants of captive-born animals.
- Collections related to the reintroduction of golden lion tamarins, Smithsonian Institution Archives
- Devra Kleiman's notebooks from Brazil, Smithsonian Transcription Center
- How the Archives Gets its Records (or, Golden Lion Tamarins Galore), The Bigger Picture, Smithsonian Institution Archives
- Going Wild: Golden Lion Tamarins released from zoo breeding efforts don’t fare well - but their offspring do better, Scientific American, April 20, 1998
- Devra G. Kleiman, Scientist Who Helped Change Zoos, Is Dead at 67, The New York Times, May 8, 2010