COQUEREL'S GIANT MOUSE LEMUR

Mirza coquereli

Geographic Distribution and Habitat
Like all lemurs, Coquerel’s giant mouse lemurs (Mirza coquereli), also called Coquerel’s dwarf lemurs or Coquerel’s mouse-lemurs, are endemic to the island of Madagascar. They are primarily found in the dry and gallery forests on the southwestern portion of the island, between the Onilahy and Tsiribinha rivers. They can also live in secondary forests, including those used for agricultural purposes, like coffee plantations.

Madagascar is well known for being a biodiversity hotspot, and it is not at all uncommon for new species to be discovered hiding in plain sight. Until recently, Coquerel’s giant mouse lemurs were the only member of their genus. But in 2005, the northern giant mouse lemur (Mirza zaza) was found to be distinct from Coquerel’s giant mouse lemur and was split into its own species. This species is smaller and lives in northwestern Madagascar.

Coquerel's giant mouse lemur range, IUCN 2020

Size, Weight, and Lifespan
On average, Coquerel’s giant mouse lemurs are 8–10 inches (20–25 cm) long and weigh between 10 and 11 oz (290–320 g), with males on the heavier side. Their lifespan in captivity is likely about 25 years, though it would be shorter in the wild.

Appearance
Like most nocturnal primates, millions of years of evolution have granted Coquerel’s giant mouse lemurs with very large, round, reflective eyes to take in every bit of available light in the dark nighttime forest. They have unusually long, fluffy tails, often rusty orange in color, that help them to balance as they nimbly maneuver through the trees. Their large ears are so thin, they’re partially transparent. They have cryptic coloring, ranging from cream on their bellies to a tan or brown on their backs, to help them to hide from predators. Adult males are larger than females, although this is the only form of sexual dimorphism they display.

Photo credit: Bernard DUPONT/Flickr/Creative Commons

What Does It Mean?

Arboreal:
Physically adapted to living primarily or exclusively in trees.

Biodiversity hotspot:
A biogeographic region with significant levels of biodiversity that is under threat from humans.

Conspecific:
​Belonging to the same species.

Endemic:
Native or restricted to a certain area or country.

Gallery forest: 
A forest that serves as a corridor along rivers or wetlands and projects into landscapes that are otherwise sparsely treed, such as savannas, grasslands, or deserts.

​Gestation Period:
The time of pregnancy from conception until birth. 

​Nocturnal: 
Active at night.

Secondary forest:
A forest that has regrown after a major disturbance, such as fire or timber harvest, but has not yet reached the mature state of primary forest.

Sexual dimorphism:
Distinct difference in size or appearance between the sexes of an animal in addition to difference between the reproductive organs themselves.

Slash and burn agriculture:
​A method of unsustainable farming where farmers clear land by cutting and burning flora in order to create an empty field—a “swidden”—for cultivation. Such practices are detrimental to local ecosystems.

Visit the Glossary for more definitions

Diet
Coquerel’s giant mouse lemurs are not picky eaters, consuming everything from fruit and flowers to insects and small animals. In the dry season, when food is scarce, they feed on the sugary secretions of insects to sustain themselves.​

Behavior and Lifestyle
​Coquerel’s giant mouse lemurs are nocturnal and arboreal. They spend their days in spherical nests in the trees, typically about 6–30 feet (2–10 m) high in a tree or nestled within dense vegetation. Their nests can be up to 1.5 feet (0.5 m) in diameter. They typically sleep alone, except for a mother with her offspring.

Fun Facts

​​Males’ testicles grow significantly during the mating season, growing up to five times their normal size!

Daily Life and Group Dynamics
​Coquerel’s giant mouse lemurs are typically very solitary, except for a mother with her offspring. One study found an average of only one social interaction between adults every 10 hours of observation. Conflict among conspecifics is rare, but occurs disproportionately more often between males and females than between members of the same sex. Studies have shown a variety of population densities for Coquerel’s giant mouse lemurs, ranging between 78 and 540 individuals per square mile (30–210 individuals per square kilometer).

Communication
​Coquerel’s giant mouse lemurs use a variety of communication methods, including scent marking and vocalizations such as alarm calls, territorial defense calls, and mating calls.

Reproduction and Family
Coquerel’s giant mouse lemurs primarily have a “scramble” method of mating, in which their sex ratios are roughly equivalent (although one study found that they may be slightly biased in favor of females) and males and females are evenly distributed throughout the habitat. This is in contrast to the contest model, in which there are many females that tend to stay congregated, and males that compete for mating opportunities.

Females of the species may become pregnant at any time of the year, although peak mating season begins in November and lasts through the spring. During this period of increased mating activity, males quadruple their typical home ranges and have more injuries than females. Males use breeding calls to attract mates, and, in preparation for mating, their testicles grow significantly—up to five times their usual size. Females are fertile for one day every 19 to 30 days. Females often mate with more than one male and can even give birth to a single litter fathered by multiple males.

Coquerel’s giant mouse lemurs don’t form pair bonds, and after mating, the female takes on the role as the sole provider to her offspring. Their gestation period is three months, after which one or two infants are typically born. They leave their nest at about three weeks of age. Mothers nurse their young multiple times per day, and they have to return back to their nest several times every night while foraging. Young become sexually mature when they are about a year old. It is unknown how long offspring stay with their mothers. In one study, a female frequently shared a nest with a male, believed to be her son, until the male was over two years old. Their generation length is 5 years.

Photo credit: Bernard DUPONT/Flickr/Creative Commons

Ecological Role
​​As small mammals, Coquerel’s giant mouse lemurs are likely targeted by a number of predators including snakes, owls, and fossas. They also play a role in seed dispersal due to their fruit-eating.

Conservation Status and Threats
Coquerel’s giant mouse lemurs are considered “Endangered” by the International Union for Conservation of Nature (IUCN, 2018). They are believed to have undergone a population decline of more than 50% over the past 15 years, or three generations. Because their major threats are expected to continue, they are predicted to sustain a further population loss of more than 50% over the next 15 years. In the longer term, they are also expected, like virtually every species on Earth, to be impacted by climate change.

The major threats against Coquerel’s giant mouse lemurs are habitat loss and quality decline and hunting pressure. Madagascar has suffered a tremendous amount of deforestation in recent years, losing 37% of its forest cover between 1973 and 2014. Between 2010 to 2014, the deforestation rate was a whopping 1.1% per year. Nearly half of the forests on the island are within 330 feet (100 meters) of the forest edge, indicating severe forest fragmentation. The major reason for deforestation in the Coquerel’s giant mouse lemur’s range is slash-and-burn agriculture and charcoal production.

Conservation Efforts
​Coquerel’s giant mouse lemurs are listed on Appendix I of the Convention on International Trade in Endangered Species (CITES). Portions of their habitat are protected by preserved lands, including Zombitse-Vohibasia National Park, Isalo National Park, Andranomena Special Reserve, Tsingy de Bemaraha National Park, and Tsingy de Namoroka National Park.

References:

  • https://www.iucnredlist.org/species/13584/115567718
  • http://www.edgeofexistence.org/species/coquerels-giant-mouse-lemur/
  • https://animaldiversity.org/accounts/Cheirogaleidae/
  • Kappeler, P. M. 1997. Intrasexual selection in Mirza coquereli: evidence for scramble competition polygyny in a solitary primate. Behav Ecol Sociobiol 45:115-127.
  • Radespiel, U., P. Ehresmann, E. Zimmermann. 2001. Contest versus scramble competition for mates: The composition and spatial structure of a population of gray mouse lemurs (Microcebus murinus) in North-west Madagascar. Primates 42. https://doi.org/10.1007/BF02629637
  • Stanger, K. F., B. S. Coffman, M. K. Izard. 1995. Reproduction in Coquerel’s dwarf lemur (Mirza coquereli). American Journal of Primatology 36:223-237.

Written by K. Clare Quinlan, May 2021