COLLARED BROWN LEMUR

Eulemur collaris

Geographic Distribution and Habitat

The collared brown lemur (Eulemur collaris), also called the red-collared lemur, is native to the humid forests of the high plateaus in southeastern Madagascar. Their range is bound by the Mananara River to the north, which separates it from the range of the gray-headed lemur (also called the white-collared lemur, E. cinereiceps), except for a few isolated populations that overlap in range. The western limits of their range are bounded by the forests of the Kalambatritra region and reach south to the city of Fort-Dauphin. They live up to an elevation of about 6,150 feet (1,900 m).

TAXONOMIC NOTES

Collared brown lemurs were formerly considered a subspecies of the common brown lemur (E. fulvus), but were elevated to full species status in the early 2000s.

Collared Brown Lemur range, IUCN 2022

Size, Weight, and Lifespan

Collared brown lemurs weigh about 5.5 pounds (2.6 kg) on average, with a head and body length of 16 inches (41 cm). Their tail adds another 22 inches (55 cm) to their overall length. They live about 25 years in the wild, but they have been known to live up to 36 years in captivity.

Appearance

Collared brown lemurs are medium-sized as far as lemurs go, with a thick, fluffy coat. Their orange eyes are wide and well-adapted for active nights. They sport the characteristic snout that most lemurs have, as well as fluffy tufts of fur on their cheeks. They have what are known as “tooth combs”—bottom incisors that tilt forward and are used as a “comb” for grooming. They are sexually dichromatic, meaning that males and females have different coloration. Males have a more gray coat in contrast to the females’ orange-brown coat. Males also have a darker tail and a dark stripe down their spine. Females’ faces are light gray, while males’ are dark gray. Males also have more prominent cheek tufts than their female counterparts.

Diet

Collared brown lemurs are largely frugivorous—fruit eaters. They supplement their diets with relatively small amounts of flowers, leaves, nectar, bark, insects, and even small vertebrates like chameleons. They occasionally eat soil as well, which provides them with important minerals. Some of the most important plants in their diet come from the genera Syzigium, a genus of flowering plants in the myrtle family; Dypsis, a genus of evergreen palms; and Uapaca, a genus of flowering plants that are native to Africa and Madagascar. They have been documented eating from more than 75 different plant species, although the true number is likely even higher.

Behavior and Lifestyle

Collared brown lemurs are largely arboreal, meaning they spend most of their lives in the trees, although they do occasionally travel on the ground. They are considered to be cathemeral—that is, they are neither strictly diurnal or nocturnal and instead are irregularly active at all times of the day. Research has shown that their daily schedule is heavily influenced by the amount of moonlight on a given night and by the length of the day. On the whole, they are not particularly active, spending about two-thirds of their time resting. They are most likely to be up and about in the early morning or late evening, when they tend to feed. In the wet season, when food is abundant, the lemurs like to stick close together as a large group, feeding together. In the dry season, when food is harder to find, they tend to split up into smaller groups.

Fun Facts

Collared brown lemurs are one of the most important seed dispersers for many plant species throughout their range. However, research shows that this wasn’t always the case. Madagascar used to be populated with a wide variety of now-extinct lemur species, called “subfossil lemurs.” The term “subfossil” refers to remains that have not finished the fossilization process, often because not enough time has passed for the remains to become fully fossilized. In the case of the subfossil lemurs, they are all believed to have gone extinct within the last 2,000 years, coinciding with the arrival of humans on Madagascar. The subfossil lemurs were all larger than today’s species, so are sometimes referred to as the “giant lemurs,” with one species, Archaeoindris fontoynontii, estimated to have been the size of today’s gorillas. The subfossil lemurs were the main seed dispersers of the region’s plants, evolving alongside the plants over millions of years to form this symbiotic relationship, a process called “coevolution.” Researchers believe that when the subfossil lemurs went extinct, collared brown lemurs filled that crucial role for the plants in their range. Without them, there would have likely been much more severe ecological disruption.

Daily Life and Group Dynamics

Collared brown lemur groups are usually composed of multiple males and multiple females, and can range in size from just two up to 22 individuals. Sadly, smaller groups are becoming more common as their habitat is fragmented by human disturbance. While most lemur species feature female dominance, collared brown lemurs are more egalitarian, with no clear hierarchy system in their groups and no one sex dominant over the other. While they are not overly territorial, groups maintain boundaries of their home ranges via scent marking and vocalization. When they encounter other groups, they may react with hostility, but they are almost never violent with one another.

Communication

Collared brown lemurs use a wide variety of communication methods. They use calls to maintain their home range boundaries, signaling this information to other groups via their vocalizations. Scent marking, or olfactory communication, is another extremely important method that uses the scent glands located on their wrists. They use scent marking to protect their home range and in the process of courting mates. Allogrooming—the grooming of others—is an important form of tactile communication as it allows groupmates to bond with each other. Visual communication, like the use of body posture and facial expressions, is also likely an important tool as well.

Reproduction and Family

Females are only receptive for a 24-hour period during the breeding season, which occurs in May and June. Males court receptive females by scent marking around them and, however odd it may seem to humans, even urinating on them. Males are more aggressive during the breeding season as they compete for a limited number of reproductive-age females. Some males may even be ousted from the group during this time. Once a female is pregnant, she gives birth four months later, usually in September or October. Singletons are most likely but twins are not rare, which is unusual for primates, most of whom only ever birth one baby at a time. Both parents help to raise the young, which likely contributes to the lower-than-average infant mortality rates that collared brown lemurs boast compared to other lemurs with low paternal involvement. When the babies are three to four months old, they begin to wean. They become sexually mature at about three years of age, and the reproductive process starts over with the new generation.

Ecological Role

Collared brown lemurs are particularly important seed dispersers. They eat from a wide variety of plant species, and they are notoriously messy eaters, often dropping seeds on the ground when they eat fruit. Seeds also travel through their digestive system and are later distributed in their droppings. Collared brown lemurs are sympatric with, meaning they live alongside, the gray-headed lemur (E. cinereiceps) in some small pockets of their range.

Conservation Status and Threats

The International Union for Conservation of Nature lists the collared brown lemur as Endangered (IUCN, 2018) appearing on the IUCN’s Red List of Threatened Species. Collared brown lemurs are believed to have undergone a dramatic population loss over the last 24 years, or three generations. They are believed to have lost approximately 50% of their population, largely due to a decline in habitat area, quality, and connectedness. Because habitat loss has not slowed and is not easily reversible, it is believed that this trend will continue in the next few decades.

The primary causes of habitat loss are charcoal production and slash-and-burn agriculture. The mining of ilmenite, which is the most important ore for titanium production, also threatens populations of collared brown lemurs that live along shorelines. In Madagascar, 37% of all forest cover was lost between 1973 and 2014, with a 1.1% per year loss in forest cover from 2010 to 2014. Collared brown lemurs are particularly at risk from habitat fragmentation, the process of breaking wide swaths of forest down into small, disconnected “patches” of habitat. Nearly half of all of the island’s forest area is located less than 330 feet (100 m) from the edge of the forest. Because it is difficult for the lemurs to travel between the forest patches to breed, many populations of collared brown lemurs in forest fragments have very low levels of genetic diversity, which can cause serious health issues within the population. Collared brown lemurs are not known to travel long distances, especially not on the ground, so they are left mostly confined to small habitat patches. When they are forced to travel between forest patches on the ground, they are extremely vulnerable to predators, especially birds of prey.

Unsustainable hunting has also put pressure on the species, as they are hunted widely for food and sometimes collected for the pet trade. Climate change also poses a significant threat to collared brown lemurs in the coming decades. One research study has estimated that more than half of the species’ 2000 range will be gone by the year 2080.

Conservation Efforts

Collared brown lemurs are listed in Appendix I of the Convention on International Trade in Endangered Species (CITES), an international agreement between governments whose goal is to ensure that international trade in specimens of wild animals and plants does not threaten their survival.

Collared brown lemurs live in the Mandena Conservation Zone, the Sante Luce Conservation Zone, the Sante-Luce Primate Reserve, and within Midongy de Sud and Andohahela National Parks. Promoting habitat connectivity is a high priority for collared brown lemur conservation. Even small patches of forest can be immeasurably beneficial if they provide a connection, like a stepping stone, between disconnected forest patches. This opens up new areas of habitat to the lemurs for food resources and, crucially, genetic diversity.

Conservationists often look for “win-win” conservation actions, in which the target species is benefited as well as the local people who share space with the species. The Duke University Lemur Center has found one such action by distributing fuel-efficient wood-burning rocket stoves to local Malagasy families. These stoves use almost 50% less fuel than other cooking methods, which reduces dependence on wood and charcoal, the demand for which is a major threat to Madagascar’s forests. In addition to the ecological benefits, the rocket stoves result in better indoor air quality, which means that women and children in particular have fewer respiratory health issues. Actions like this improve life for everybody, human and otherwise, and improve the relationships between local people and the natural world around them.

References:
  • Bertoncini, S, D’Ercole, J, Brisighelli, F, et al. 2017. Stuck in fragments: Population genetics of the Endangered collared brown lemur Eulemur collaris in the Malagasy littoral forest. Am J Phys Anthropol. 163: 542–52. https://doi.org/10.1002/ajpa.23230
  • Bollen, A., Van Elsacker, L. & Ganzhorn, J.U. 2004. Tree dispersal strategies in the littoral forest of Sainte Luce (SE-Madagascar). Oecologia 139: 604–16. https://doi.org/10.1007/s00442-004-1544-0
  • Donati, G, Campera, M, Balestri, M, et al. 2020. Life in a fragment: Evolution of foraging strategies of translocated collared brown lemurs, Eulemur collaris, over an 18-year period. Am J Primatol. 82. https://doi.org/10.1002/ajp.23106
  • Eppley, T.M., Balestri, M., Campera, M. et al. 2017. Ecological flexibility as measured by the use of pioneer and exotic plants by two lemurids: Eulemur collaris and Hapalemur meridionalis. Int J Primatol 38: 338–57. https://doi.org/10.1007/s10764-016-9943-8
  • Godfrey, L. and W. Jungers. 2003. The extinct sloth lemurs of Madagascar. Evolutionary Anthropology 12:252-63.
  • Roberts, S., Racevska, E., Donati, G. 2020. Observation of the natural re-colonisation of a littoral forest fragment by the endangered red-collared brown lemur (Eulemur collaris) in southeast Madagascar. Lemur News 22.
  • https://www.iucnredlist.org/species/8206/115562262
  • https://nationalzoo.si.edu/animals/collared-brown-lemur
  • https://lemur.duke.edu/discover/meet-the-lemurs/red-collared-lemur/
  • https://lemur.duke.edu/protect/sava-conservation/
  • https://www.lemurreserve.org/lemurs/collared-brown-lemur-2/
  • https://animaldiversity.org/accounts/Eulemur_fulvus/
  • https://www.nhm.ac.uk/discover/news/2020/june/only-known-drawing-of-extinct-giant-sloth-lemur-found-in-cave.html

Written by K. Clare Quinlan, December 2023