Species: Leontopithecus rosalia
Physical Description: The Golden Lion Tamarin was first described to the European world by the Jesuit Pigefetta, chronicler of the voyage of Magellan. He described them as "beautiful simian-like cats similar to a small lion." Tamarins have a pale to rich reddish gold coat and a long, backswept mane covering ears framing an almost bare face. Their fingers and hands are long, nimble, and partially webbed, with non-opposable thumbs. The average adult weighs between 1-2 pounds and is 8-13 inches in length (head and body; including tail, about 24 inches long). Golden Lion Tamarins are monomorphic (the sexes look alike) and have a maximum age of 15 years
Geographic Location: The Golden Lion Tamarin inhabits the Brazilian Atlantic Forests Global 200 Ecoregion.
In the 19th century, the Golden Lion Tamarin inhabited Brazil in the coastal forests of the states of Rio De Janeiro and Espirito Santo south of the Rio Doce. By 1981 it was known only from the remnant forests in the Rio Sao Joao Basin in the state of Rio de Janeiro in an area of occupied habitat probably totaling considerably less than 900 sq km (350 sq mi). The wild population is currently fragmented into 17 different subpopulations in isolated forest patches throughout its small range.
More than 90% of the original Atlantic coastal forest, which contains the Golden Lion Tamarin's habitat, has been lost or fragmented to obtain lumber and charcoal and to clear out areas for plantations, cattle pasture, and development. Capture for zoo's and private collection has also contributed to it's decline.
Ecology: Golden Lion Tamarins inhabit the lowland coastal rainforest region in Southeast Brazil in the 5000 hectare Poco das Antes Biological Reserve. They are diurnal and arboreal, typically dwelling at heights of 3-10 meters above the forest floor. Their forest environment provides them with many vines and bromeliads, which they often feed and drink out of. They find shelter and sleep in the holes of hollow trees. Their total population in the wild has been estimated by different sources with values ranging form 400-800.
Diet: They consume mostly fruits and insects, although they are known to also eat small animals including invertebrates, lizards and snakes. A specific percentage could not be found. Their long, slender fingers allow them to probe into crevices in the bark of trees in search of food. This technique is known as micro-manipulation.
Social Organization: Group size ranges from 2-8 with an average of 7, consisting of multiple males and females (rarely is there only one male or female). Their mating system is mainly monogamous with a few cases of polygyny. Both males and females have been observed to leave the group to form a new group with new territory. There are clear hierarchies for females- there is a dominant female who is generally to be the only producer, and usually there is only one male who mates with the females in the group. There was very little information about kinship but is was found that usually the daughter of the highest ranking female would be the one most likely to reproduce. In breeding has been noticed to be a problem because of the close kinship among individuals combined with reduced populations. Lion Tamarins are very protective of their territory and use calls and scent marks to mark their territory, although fighting amongst these Tamarins is rare. Members of the group usually forage for food on their own rather than finding it as a group. Aggression is most notable in members of the same age and sex, with 20% of hostile encounters ending in death. Young, lower ranking individuals have been found to fight more often than higher ranking ones.
Reproduction: Birth seasonality is between the months of August and September with a gestation length of about 132 days. Lion Tamarins reach sexual maturity at about 9-13 months for males and 18-24 months for females. Litter size usually results in twins but can be up to four. Infants weigh about 50-75 grams when they are born with a mortality rate of about 50 %.
Parental Care: Infants are usually only carried by the female for a few days before the male takes over responsibility for the offspring. As for being carried by the male, it usually lasts for about 4 months. Weaning occurs at about 90 days and offspring usually stay with their parents until they reach sexual maturity. Relationships with parents usually last for about 2 years in males because the majority of them leave to start their own group. Infanticide has been found to occur mainly in females when the mother kills her eldest daughter for fear that she will lose her dominant position. I could not find when the infants begin to walk.
Rylands, Anthony B. Marmosets and Tamarins: Systematics, Behaviour, and Ecology. Oxford University Press, 1993