The golden lion tamarin is a squirrel-sized monkey found in southeastern coastal Brazil, in dense lowland rain forest. It is named for the mane of fur around its head and its bright coloration, which ranges from pale gold to a rich reddish-gold, with variable black markings, particularly on the tail.
The lion tamarins are the largest of the marmoset and tamarin group. More than 30 species of marmosets and tamarins are found in the Neotropics, from Panama through much of South America. Marmosets and tamarins differ from other monkeys in their small size and in having claws instead of flat nails on most of their digits (only the big toe has a flat nail). These claws help the small monkeys cling to trunks and branches.
Lion tamarins differ from other marmosets and tamarins in having long, narrow hands and long fingers. Keep reading to find out how they use these long hands and fingers.
Longevity
Golden lion tamarins have been known to live beyond 20 years of age in the protected environment of a zoo. In the wild they may live as long as 17 years, but most fall victim to predators, injury or illness long before reaching this age.
Reproduction
Marmosets and tamarins, including the golden lion tamarin, have unusual reproductve patterns compared to most other monkeys. A female marmoset or tamarin usually produces twins and sometime triplets - for all other monkeys, twins are the exception rather than the rule. Marmoset and tamarin twins (or triplets) are usually fraternal, not identical, but they share a single placenta.
Another way in which marmosets and tamarins are unusual is in infant care. In most monkey species, only the mother carries a new baby. But in marmosets and tamarins, the father as well as older brothers and sisters will also help carry the baby, giving mom some rest. In the golden lion tamarin, the mother usually carries the baby 24 hours a day for the first week or so after the birth, before first the father and then the older siblings start to help.
Gestation period for the golden lion tamarin is 125-131 days. In the wild, most golden lion tamarin babies are born from September through December, near the beginning of the Brazilian summer, which is also the wet season in the part of Brazil where the tamarins are found. Usually, a female produces just this one litter a year, but sometimes, apparently when weather and other conditions produce a heavy fruit crop, so there's a lot for the tamarins to eat, a female might produce a second litter in January or February. In zoos, where there is plenty of food, female golden lion tamarins may have as many as three litters in one year.
Behavior
Golden lion tamarin groups may be as large as 12-14 individuals, but most groups are smaller, with 5 or 6 being a typical group size. Many golden lion tamarin groups are composed of an adult pair and their young from recent litters. However, some groups contain two adult males, both of which may breed with the reproductive female. Some groups may also contain two breeding females. Golden lion tamarin groups are very territorial - when neighboring groups meet, they face off, calling loudly and chasing each other, but actual fights or injuries are rare. The average territory for a golden lion tamarin group is about 100 acres (40 ha). Why would a small group of monkeys need so much space? Believe it or not, they may need that much space to find enough food, particularly in the Brazilian winter, when fruit and insects are scarce.
Golden lion tamarins sleep in protected spots at night - often a cavity in a tree trunk, but sometimes in the middle of a dense clump of bamboo or in a large bromeliad. What's a bromeliad? Find out under "adaptations" below. Potential tamarin predators include large hawks, small cats like the ocelot, the tayra (a large weasel-like mammal), and large snakes.
Adaptations
Lion tamarins have long, narrow hands and long fingers, which they use to probe for insects and other small animals in places their prey might be hiding - under tree bark or inside a curled dried leaf. One of their favorite places to find insect prey is between the leaves of epiphytic bromeliads. Bromeliads are a group of plants found mostly in the New World tropics - the most well-known bromeliad is the pineapple plant. Many bromeliads are epiphytic - meaning they grow on the trunks or branches of trees or bushes rather than on the ground. Lion tamarins probe between the leaves of these "arboreal" bromeliads to find insects and other prey. They also use large bromeliads as sleeping locations - the entire tamarin group disappears into the middle of the dense mass of vegetation as dusk approaches.