The golden bamboo lemur (Hapalemur aureus ), bokombolomena or varibolomena in Malagasy, is a medium-sized bamboo lemur endemic to south-eastern Madagascar.
Golden bamboo lemurs are amongst most endangered mammals in the world. They have pale orange fur on their backs with brown to gray guard hairs and yellowish undersides. Their face is black, with a short muzzle, and golden cheeks, throat, and eyebrows and short hairy ears. The males and females are usually similar in appearance, with females often being slightly more grayish on their backs.
The Golden bamboo lemur occurs in southeast Madagascar, in Andringitra Nature Reserve and Ranomafana National Park, in the tropical, moist, rainforests of giant bamboo.
Golden bamboo lemurs live in groups which often do not exceed four individuals. Typically the group has one adult male and female, along with younger adults or juveniles, being a family of a monogamous pair with their offspring. Groups occupy territories as large as 80 ha, but generally travel less than 400 m each day. These lemurs are crepuscular or diurnal, with a defined midday rest period. Most of their waking hours are spent foraging. Golden bamboo lemurs are very vocal, and have at least two different calls. They make a quiet “hard grunt”, which is possibly a contact call between family members, being sometimes responded to and then repeated by others, as well as loud call at night which may be for territorial purposes.
Golden bamboo lemurs are herbivores, eat mostly new shoots, leaf bases and bamboo grasses, particularly creepers of the Madagascan giant bamboo.
Golden bamboo lemurs are a monogamous species, mate with strictly one partner during a breeding season. The season runs from July to August. The gestation period is for approximately 138 days, and births occur once per year, in December. Usually a single baby is born, requiring several months of lactation and maternal care. Unlike other species of bamboo lemur, females nest with their young for their first 10 days to 2 weeks in secluded areas in dense vegetation. Golden bamboo lemurs practice oral transport and infant parking, mothers leaving their infants while foraging leaving them for 200 minutes on average, while they go up to 250 meters away. Weaning occurs at 6 to 8 months of age. Young stay with their parents in a family group until they are about 3 years old, when they start to disperse.
The Golden bamboo lemur is under threat by the ongoing loss of forest habitat as a result of the timber extraction and slash-and-burn agriculture. Even protected forests in Ranomafana National Park are under threat from illegal logging and other exploitation. These lemurs may be at risk also from the pet trade and from being hunted for food.
According to the IUCN Red List, the total Golden bamboo lemur population size is 630 individuals, with fewer than 250 mature individuals, including a total estimated population of 69 lemurs within Ranomafana National Park. Currently Golden bamboo lemurs are classified as Critically Endangered (CR) and their numbers are decreasing.
Frugivorous lemurs have been implicated as important vectors for seed dispersal in rainforests, but it is unknown what role they may play in propagation of bamboo.