CROWNED LEMUR

Eulemur coronatus

Geographic Distribution and Habitat

The crowned lemur (Eulemur coronatus) is endemic to Madagascar. They are found nowhere else in the world. In fact, all lemurs are endemic to Madagascar—you will never find one living naturally anywhere else. Crowned lemurs live on the northernmost tip of Madagascar, called Cap d’Ambre, and occur as far south as the Mahavavy River. They live from sea level up to an elevation of 4,600 feet (1,400 m) and prefer to live in semi-deciduous forests. However, they are extremely flexible with their habitat, living in tropical forests and savannas, and even surviving in degraded habitats and agricultural areas.

Crowned lemur range, IUCN 2020

Size, Weight, and Lifespan

As the smallest members of the Eulemur genus, crowned lemurs weigh 2.1 to 2.5 pounds (1.1–1.3 kg) on average and are about 13 inches (34 cm) long. Their tails add another 18 inches (45 cm) to their length. Males and females do not have a substantial size difference between them, which is typical of lemurs. They can live up to 20 years in the wild and 30 in captivity.

Appearance

Crowned lemurs have a body shape that is typical of other lemurs, with long arms and legs and a dog-like snout that protrudes from their face. Their orange eyes are very large, with relatively small pupils, and their ears are rather small and don’t protrude far from their heads. Of all the lemur species, crowned lemurs are one of the most sexually dimorphic, meaning that males and females look different from each other. Specifically, they are sexually dichromatic, meaning that males and females have different color patterns, despite otherwise looking similar. Females are mostly gray with an orange “tiara,” while males are reddish-brown over most of their body, with a black triangle on their forehead. Babies look like adorable, pint-sized copies of their parents.

Diet

Crowned lemurs are largely frugivorous, meaning that they mostly eat fruit. In fact, fruit makes up 80–90% of their diet. They supplement their diet with young leaves, flowers, pollen, and insects. In the dry season, they rely more heavily on flowers for their dietary needs. In addition to this natural diet, crowned lemurs have also been observed raiding farms and plantations for crops. They have been known to eat and lick soil as well—a perplexing behavior, maybe, but one that supplies them with necessary minerals. In dry areas and times of the year, they have been known to venture into caves to find water.

Behavior and Lifestyle

Crowned lemurs are known to thoroughly explore their habitat—climbing high into trees and traversing by foot on the forest floor. However, they tend to spend most of their time among thick vines and foliage, and on the very end branches of trees. They are loosely diurnal—while they are more active during the day, they often have periods of activity in the middle of the night and often take long afternoon naps. They spend a lot of time grooming themselves and each other. Like other lemurs, they even have a specially adapted “dental comb” formed by their lower incisors and canine teeth to help with grooming.

Fun Facts

Crowned lemurs demonstrate their agility in a manner that few other primates can boast. They have been observed delicately making their way across the Tsingys, two plateaus in northwest Madagascar that are composed of soluble rock types, such as limestone. These minerals dissolve over time and leave behind knife-edged rock formations called “karsts” that jut up precariously from the ground. “Tsingys,” from the Malagasy language, translates into “where one cannot walk barefoot”—clearly a warning that does not apply to crowned lemurs!

Daily Life and Group Dynamics

Crowned lemurs live in small groups, usually only five or six individuals, but up to 15 have been observed. These larger groups typically split up into smaller groups to forage. Occasionally, individuals will forage by themselves before returning to their group. Their home ranges are usually 25–37 acres (10–15 ha) in area. Crowned lemurs are one of only three species in their genus to display female dominance over males. Females get first pick of foraging spots and their choice of mates.

Communication

Crowned lemurs use a wide variety of communication methods, such as vocal, tactile, and olfactory. “Piercing yaps,” as researchers have described them, are emitted by crowned lemurs when they break off into sub-groups to forage. These loud calls can be heard across long distances, and help to keep the sub-groups in contact with each other. Although primates don’t typically have an adept sense of smell, lemurs are Strepsirhines, which means that they have moist noses (like dogs and cats). This enhances their sense of smell. Scent marking is another useful tool at the lemurs’ disposal. One study of captive crowned lemurs found that males use scent marking more often than females. Males use scent glands found on their heads, wrists, and genitals to mark different areas, including other lemurs. Female lemurs were found to only use genital scent marking. Males also have a more diverse chemical profile in their pheromones—a total of 38 components found in male scent marks compared to females’ 26. The scent marks are likely used to mark their territory, defend resources, and guard mates.

Reproduction and Family

Crowned lemurs are polygynous, meaning that males have multiple mating partners but each female typically only mates with one male. The reproductive cycle of female crowned lemurs lasts about 24 days. When not in estrus, the female’s vulva is physically closed. Their reproductive cycle is highly seasonal, with most matings occurring between May and June, and births four months later in September and October. This seasonal reproductive strategy makes sense, as babies are born at the beginning of the rainy season when food becomes abundant. In drier areas, births occur later in the year. That way, a lactating mother is better able to meet her calorie needs to feed her baby. Single babies and twins are born with about equal frequency, which is a fairly unusual characteristic for primates who almost always have a single baby (with the notable outliers of tamarins and marmosets). The babies weigh about 2 oz (60 grams) on average at birth. Babies are carried on their mothers’ bellies for about three weeks, before moving to their backs. They nurse from their mother for the first six or seven months of their lives, and they gradually gain more independence until they reach sexual maturity at about 20 months of age. It is not known what role, if any, males play in raising young.

Photo credit: Charles J. Sharp/Creative Commons
Ecological Role

Crowned lemurs are sympatric with—that is, they live in the same areas as—Sanford’s brown lemur (E. sanfordi). Unlike Sanford’s brown lemurs, however, crowned lemurs are less picky about their habitat, and so they can live in more open, dry, and degraded areas which the brown lemurs avoid. Aggressive encounters between crowned lemurs and Sanford’s brown lemurs have been recorded, but it is not known how common these antagonistic encounters are. Because of their fruit-heavy diet, crowned lemurs play a role as seed dispersers as well. In fact, there are at least 20 plant species, including three that are threatened with extinction, for which crowned lemurs are one of the only seed dispersers. They are likely predated upon by animals like predatory birds and fossas, a cat-like mammal.

Conservation Status and Threats

The International Union for Conservation of Nature lists the crowned lemur as Endangered (IUCN, 2018), appearing on the IUCN’s Red List of Threatened Species. They are expected to undergo a population loss of more than 50% over the next 25 years, which is about three generations. This is due to the decline of habitat area and quality, as well as hunting pressures that the lemurs unfortunately face.

Madagascar, as a whole, has lost an alarming 37% of its forest cover between 1973 and 2014, and that trend continues today. Not only is forest being lost outright, it is also becoming fragmented. The vast expanses of forests that the island once boasted are dwindling. Now, almost half of the forest on the island is located less than 330 feet (100 m) from the forest’s edge. Crowned lemurs are particularly impacted by this habitat fragmentation. This habitat loss is largely a result of slash-and-burn agriculture. This kind of farming, in contrast to sustainable agriculture that supports both humans and the surrounding ecosystem, results in the clear-cutting and burning of forest cover to make room for crops. Not only does slash-and-burn agriculture come with major impacts on the environment, but it is also not ideal for the farmers, who must constantly move to new land every few years when soil nutrients are depleted. In addition, habitat is also being lost due to charcoal production, sapphire and gold mining, and illegal logging. The crowned lemur population is also threatened by hunting. They are hunted for meat, even within national parks, and are sometimes killed in retaliation for crop raiding. They are also regularly collected for the local pet trade.

Climate change is another significant threat to crowned lemurs. They are expected to lose 93% of their range between 2008 and 2080 due to climate change alone. Madagascar faces powerful cyclones that can damage ecosystems and harm people. Climate change is expected to increase the frequency and intensity of these storms, and increased rainfall will lead to flooding and soil erosion. Other areas of the island will experience less rainfall, leading to droughts—which have already caused hardship for the local people, many of whom unfortunately live in abject poverty. The impact of droughts on the ecosystem is still being assessed, but more than likely it is placing a significant amount of pressure on the many threatened and endangered species that call the island home. Sea level rise will exacerbate many of these issues, as Madagascar has the longest coastline of any country in Africa. Flooding will likely get even worse, and the impact of storms will increase.

Conservation Efforts

Crowned 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.

Crowned lemurs are protected within a number of protected areas, including Ankarana and Montagne d’Ambre National Parks, and in Analamerana and Forêt d’ Ambre Special Reserves. Population densities of the lemurs have been found to be higher within these areas, which demonstrates how important they are to the species. Still, more work is needed to enforce the protection in these areas, as illegal hunting has been known to occur within them.

Work is also being done to reduce the impact of human agriculture on natural ecosystems. For example, agroforestry is a method whereby crops are planted alongside trees, without the need for forest clearing. This kind of planting can result in higher crop yields, as the trees keep the soil intact, bring nitrogen from the atmosphere into the soil, a process called nitrogen fixation, and provide nutrients in the form of dropped leaves which then decay. It also reduces the need for inputs like fertilizers and pesticides. And because the forest doesn’t need to be cleared, it helps to protect habitat, particularly for adaptable species like crowned lemurs. This solution also has benefits for the local people, which is an important goal in a country with widespread poverty.

References:
  • Mercado Malabet, F., H. Peacock, J. Razafitsalama, C. Birkinshaw, I. Colquhoun. 2020. Realized distribution patterns of crowned lemurs (Eulemur coronatus) within a human-dominated forest fragment in northern Madagascar. Am J Primatol., 82. https://doi.org/10.1002/ajp.23125
  • Rakotondrina, A., R. Andriantsimanarilafy, J. Andrinanarivelo, L. Benjamin, J. Zaonarivelo, J. Ratsimbazafry. 2023. Population assessment of the crowned lemur (Eulemur coronatus) in the Bobaomby Area, Northern Madagascar. Primate Conservation, 37.
  • Steffens, K. J., J. Sanamo, J. Razafitsalama. 2022. The role of lemur seed dispersal in restoring degraded forest ecosystems in Madagascar. Folia Primatologica, 93(1): 1-19. doi: https://doi.org/10.1163/14219980-20210801
  • https://www.iucnredlist.org/species/8199/182239524
  • https://www.ecologic.org/our-impact/challenges/slash-and-burn-agriculture
  • https://lemur.duke.edu/discover/meet-the-lemurs/crowned-lemur/
  • https://zooatlanta.org/animal/crowned-lemur/
  • https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8300250/
  • https://www.usaid.gov/madagascar/environment-and-climate-change
  • https://animaldiversity.org/accounts/Eulemur_coronatus/

Written by K. Clare Quinlan, July 2023