Golden lion tamarins are among the most strikingly colored of all mammals. They have a magnificent reddish-gold coat and a long, backswept mane that covers the ears and frames the dark, almost bare face. They have narrow hands and feet, long canine teeth, and short incisor teeth like other tamarins and marmosets. Golden lion tamarins (GLTs) are small monkeys, weighing 17 to 24 ounces (481.9 to 680.4 g) and measuring six to ten inches (15.2 to 25.4 cm) in length with a tail of about 12 to 15 inches (32 to 40 cm).

They move quadrapedally through the trees and can spring and leap between branches and vines.

find out about our conservation efforts with the golden lion tamarins

Taxonomy

Geographical Distribution

In the wild, GLTs are distributed in four sub-populations. The largest population is in the Poço das Antas Biological Reserve and in the forests located near the Reserve on the opposite bank of the Sao Joao River. Poço das Antas is protected by IBAMA, the Brazilian Environmental Institute. The other GLT sub-populations are located in unprotected forest in highly populated regions and are subject to threats such as deforestation and hunting.

Since 1994, isolated wild groups of GLTs found in very small and degraded forests have been translocated to larger continuous forest. A number of groups were translocated to Uniao. The presence of tamarins on this land helped to transform this area into a Biological Reserve in 1998.

The reintroduced (captive-born) GLTs have been released in private forests/farms near to Poço das Antas. The largest reintroduction site is Fazenda Rio Vermelho. To date there are 26 farms that have GLTs living on them.

Diet in the Wild

GLTs are omnivorous, feeding on fruits, insects, and small invertebrates. Any smaller animal is possible food. They actively search crevices, bark, bromeliads and other hiding places for their prey. They use their long, slender fingers and hands to probe into these areas; this behavior is called micromanipulation.

Food is shared on occasion. Sharing is both passive (i.e. tolerated stealing) and active, with the food actually offered to another animal. Usually the food goes from older to younger animals. Often young animals will make a rasping noise (known as an infant rasp) as they try to take food from another animal. It is uncommon that these tamarins will share food with others outside of their family members.

Zoo Diet

In the Zoo GLTs are fed fruits, carrots, sweet potatoes, green beans, hard-boiled eggs, mealworms, crickets, and canned marmoset diet.

Social Behavior

As with other lion tamarins, golden lion tamarins are a social species. In the wild, they are found in groups of two to eight family members. The groups comprise a breeding pair, offspring of one or two litters and possibly other relatives. Golden lion tamarins groom much like other primates. The juveniles exhibit play behavior, which includes chases and wrestling.

Tamarin groups actively defend a territory against other GLTs. Territories average about 100 acres (40 hectares). The defense of a territory is accomplished through vocalizations and scent marking during ritualized group encounters. Actual fighting seldom occurs, if at all.

In captivity, aggression can occur after sexual maturation (at 18 months) between animals of the same sex, especially between adult females. Mothers have been known to attack their older daughters, resulting in the death of one or more animals if they are not separated. Males appear to be more tolerant of each other, but will fight on occasion.

GLTs retire at dusk and sleep until after sunrise. The adults are the first out of the hole in the morning and the last to enter at night. In the zoo they sleep in nest boxes. If a nest box is available, GLTs will usually sleep in one.

Reproduction

There is one breeding pair per group. After a gestation period of about 4.5 months (128 days), the female will usually give birth to twins. At birth, the golden lion tamarin is fully furred with eyes open. It clings to its mother for the first few weeks. All members of the group will carry and care for the infants; however, the adult male usually does the largest share. The mother only takes the babies to nurse them. At about week five, it begins to expand its curiosity and experience things on its own and they are weaned at three months. As with the golden-headed lion tamarins, sexual maturity is reached at 18 months for females and two years for males. Breeding season is between September and March, the warmest and wettest time of year.

Life Span

The first year of life is the most difficult for GLTs; 50 percent of infants die during this time. The remaining individuals usually live for eight years and up to 20+ years in captivity. (longevity record is a 31-year-old male that died in 1999 at the San Antonio Zoo, TX)

Predators

Hawks and other raptors, cats, and large snakes are the main predators of GLTs. Data on predation are difficult to obtain. The tamarins give alarm calls in response to strange and/or threatening stimuli. They have a particular alarm call for large birds overhead. When that call is made, the animals head for the trunks of trees or sometimes just let themselves fall to the ground. Predators on the ground or in low vegetation elicit a different vocalization, and are mobbed by the tamarins. The alarm calls and responses seem to be genetically "hard-wired." Zoo born animals that have always lived inside make the calls and respond appropriately.

Status

About 750 GLTs are living in the wild, most in or near the Reserva Biologica de Poço das Antas in the state of Rio de Janeiro. Another 556 live in the wild as a result of reintroduction. About 480 live in Zoos.

GLTs were assessed as "Critically Endangered" in 1996 and again in 2000. GLTs are endangered because their habitat has been fragmented into small, unconnected areas, each area only capable of supporting a small number of groups. Without intervention, inbreeding would soon result in the local extinction of many of these small populations of tamarins, and eventually the entire species. Until the 1960s, GLTs were very popular as pets, but laws enacted have virtually stopped the trade. In 2003 they were downgraded to "Endangered" as a result of the nearly 30 years of conservation efforts, including the establishment of a new population through translocation to a new protected area, the Uniao Biological Reserve.

Thanks to the Golden Lion Tamarin Conservation Program, and in part thanks to the efforts of Zoo Atlanta, golden lion tamarins are making a comeback. Zoo Atlanta has been proud to be part of the effort to preserve these beautiful animals in their natural environment.