Named for their long, golden manes, Golden-headed lion tamarins are native and live only in Brazil. They are considered to be an endangered species. Their body is black, with golden to orange limbs and paws. Their tail is black with golden in color. When threatened or alarmed, these tamarins raise their beautiful mane and fluff up their fur that makes them look bigger than they really are. Males and females in this species look alike and are similar in size.
Golden-headed lion tamarins live in groups ranging from 2 to 11 individuals, with the average size ranging from 4 to 7. According to various sources, the group may consist of two adult males, one adult female, and any immature individuals, one male and one female and any immature individuals. There may also be one producing pair and a varying number of other group members, usually offspring from previous generations. These tamarins are diurnal and spend much of their time foraging and traveling within their home range to the next foraging site. They prefer to live at heights of 3-10 meters and do not even come down to sleep at night. They sleep in tree holes or vines. In order to communicate with each other, Golden-headed lion tamarins use different vocalizations. They use trills while remaining alone and clucks during foraging. Long calls are usually used when tamarins are guarding the territory.
Golden-headed lion tamarins are omnivores. They have a very wide diet and eat plants, fruits, flowers, nectar, insects and small invertebrates; which include insect larvae, spiders, snails, frogs, lizards, bird eggs and small snakes.
There is not much known on Golden-headed lion tamarins' mating system. However, according to different sources, and information on the possible social groups, it can be assumed that some may practice monogamous mating systems (one mate for life), and some may practice polyandrous mating systems (one female mates with more than one male). The breeding season occurs usually during the warm and wet season, from September through March. The gestation period lasts around 125-132 days. Females usually give birth to twins once a year. Both males and females invest energy in caring for the young, and all members of the group also help with juvenile care. Males in thus species become reproductively mature at around 24 months of age, and females at 18 months.
The main threat to Golden-headed lion tamarins is the loss of the habitat. The forest of Bahia, Brazil has been reduced to 2% due to farming, ranching, mining, and urbanization. The Atlantic Forest is highly fragmented, and the disappearance of this habitat is the main reason for the Golden-headed lion tamarin's decline. The majority of the forest was once dominated by cocoa plants through a method known as cabruca. This is a system of shade cropping in which the middle and understory trees are removed and replaced with cocoa trees. Although tamarins' habitat is reduced, they still leave old growth trees which give them a place to forage and to sleep. In 1989 farmers abandoned their cocoa plants due to a fungus that attacked their harvest. The old growth which was once available abundantly to the tamarins was destroyed to harvest timber, clear land for cattle or grow other crops. The Atlantic Forest is now a mosaic of primary and secondary forest and agricultural lands.
According to the IUCN Red List, the total population size of Golden-headed lion tamarins in the wild is around 6,000-15,000 individuals. The population size of this species in the Una Biological Reserve (Bahia, Brazil) is around 400-450 individuals. Currently, this species is classified as Endangered (EN) on the IUCN Red List and its numbers today are decreasing.
Golden-headed lion tamarins play a very important role in seed dispersal. They eat many different fruits which have seeds. These seeds pass through the tamarin's digestive tract unharmed and thus benefiting the ecosystem of their range.