Microcebus berthae

Geographic Range

Madame Berthe's mouse lemurs ( Microcebus berthae ) are endemic to Madagascar. More specifically, they are known to inhabit the Kirindy/CFPF forests in the southwestern Menabe region of the island. While Madame Berthe's mouse lemurs have also been found in surrounding areas, such as Ambadira and the Andranomena Special Reserve, their range is relatively small (less than 220 square kilometers), and none have been found north of the Tsiribihina River.

• Biogeographic Regions
• ethiopian ethiopian
  • native native

• Other Geographic Terms
• island endemic island endemic

Habitat

Madame Berthe's mouse lemurs inhabit the dry deciduous forests of southwestern Madagascar, at elevations up to 150 meters. These animals face numerous challenges in their highly specific habitat including wide daily and seasonal temperature fluctuations, seasonal food scarcity, especially of fruits and arthropods and a seven-month dry season.

• Habitat Regions
• tropical tropical
• terrestrial terrestrial

• Terrestrial Biomes
• forest forest

Physical Description

With body lengths of 9 to 11 cm, tail lengths of 12 to 14 cm and an average weight of 30.6 g, Madame Berthe's mouse lemurs are the smallest known living primates. Their dorsal fur is reddish, with a darker midline stripe running from the back of their shoulders to their tail. Their ventral fur is creamy or pale grey. Their face is more brightly colored, especially around their eyes, which are encircled by cinnamon rings and bisected by a white stripe. Like all mouse lemurs, Madame Berthe's mouse lemurs have extremely large eyes equipped with a tapetum lucidum adapted for nocturnal foraging. Likewise, these animals have bare digits, a grooming claw on their second toe, a toothcomb comprising the canines and incisors and a long tail. This species does not show sexual dimorphism.

• Other Physical Features
• endothermic endothermic
• homoiothermic
• bilateral symmetry bilateral symmetry

• Sexual Dimorphism
• sexes alike

Reproduction

Information regarding the mating system and behavior of Madame Berthe's mouse lemurs is limited, though there are several factors that might indicate a promiscuous mating system. Such indications include scramble competition, including significant home-range overlap, with male average home ranges (4.92 ha) about twice those of females (2.50 ha). Likewise, the proportionally large testicle size in males, moderate estrous synchrony, varied sleeping association patterns and lack of sexual dimorphism could all indicate a promiscuous mating system.

• Mating System
• polygynandrous (promiscuous) polygynandrous (promiscuous)

Madame Berthe's mouse lemurs breed once a year in November. Though data are lacking concerning their specific reproductive patterns, they are thought to behave similarly to gray mouse lemurs ( Microcebus murinus ), which have two-month gestation and nursing periods. This has been supported by the trapping of pregnant Madame Berthe's mouse lemurs in December and the trapping of juveniles in March and April. After nursing their one to three young to independence, female gray mouse lemurs , and presumably Madame Berthe's mouse lemurs, spend the next four to six weeks storing body fat before entering daily torpor during the dry season.

• Key Reproductive Features
• iteroparous iteroparous
• seasonal breeding seasonal breeding
• gonochoric/gonochoristic/dioecious (sexes separate)
• sexual sexual
• fertilization fertilization
• viviparous viviparous

Little is known about the parental investment of Madame Berthe's mouse lemurs, but, as in other mouse lemurs, the female likely provides care for the altricial young for about two months until they are weaned.

• Parental Investment
• altricial altricial
• female parental care female parental care
• pre-fertilization
  • provisioning
  • protecting
    • female
• pre-hatching/birth
  • provisioning
    • female
  • protecting
    • female
• pre-weaning/fledging
  • provisioning
    • female
  • protecting
    • female

Lifespan/Longevity

There is no information available regarding the lifespan of Madame Berthe's mouse lemurs, but their close relative, gray mouse lemurs are known to live about five years in the wild and up to fifteen in captivity.

Behavior

Madame Berthe's mouse lemurs are solitary, arboreal and nocturnal. They move quadrupedally along tree branches, and do most of their solitary foraging about 10 meters above the ground. Madame Berthe's mouse lemurs spend approximately half of their time sleeping alone and the other half sleeping in groups of variable composition in nests of leaves, vines, tree holes, bark and branches. There are no matrilines or other dominance hierarchies present in their individualized neighborhood social groups, but further study must be conducted on their social behavior.

A notable feature of Madame Berthe's mouse lemurs, and of other mouse lemurs, is their ability to enter into both seasonal and daily torpor. Because of their variable habitat, this ability is vital for survival. During times of drought, cold weather or when resources are lacking, they can enter into a state of torpor, significantly reducing their metabolic rate and body temperature.

• Key Behaviors
• arboreal arboreal
• scansorial
• nocturnal nocturnal
• motile motile
• sedentary sedentary
• daily torpor
• solitary solitary

Home Range

The average home range of males (0.049 km²) is approximately twice that of females (0.025 km²) and males have longer nightly paths (4470 m) than females (3190 m). There is a large overlap in male-male and male-female home ranges, but only a moderate overlap in female-female home ranges. This suggests a promiscuous mating system.

Communication and Perception

There is little information specifically regarding the communication and perception of Madame Berthe's mouse lemurs, but mouse lemurs in general are known to rely primarily on olfactory and vocal communication, with visual communication playing a very limited, if unimportant, role. While mouse lemurs lack scent glands, they use scent markers, such as urine, feces, saliva and genital secretions to alarm others, confer information about sexual attraction, mark territories and recognize other individuals. For example, females in estrus are known to increase genital marking.

The vocal cues used by mouse lemurs are specific to their species, a feature that is thought to aid in finding appropriate mating partners. Moreover, there is also great vocal variance within species, whether serving the purpose of conveying reproductive readiness or alarming others. However, because Madame Berthe's mouse lemurs are known to be a more solitary species, their use of many of these communication tactics may vary or be non-existent.

• Communication Channels
• acoustic acoustic
• chemical chemical

• Other Communication Modes
• scent marks scent marks

• Perception Channels
• visual visual
• tactile tactile
• acoustic acoustic
• chemical chemical

Food Habits

The diet of Madame Berthe's mouse lemurs is omnivorous and consists largely of "honeydew", a sugary substance secreted by the insect larvae of Flatida coccinea . They are also known to eat gums, flowers, fruits, arthropods and small vertebrates, such as chameleons and geckos . This wide dietary range is partially due to the fluctuating availability of resources in their habitat. However, their feeding niche remains small and specialized despite seasonal variation, and becomes even narrower in the dry season.

• Primary Diet
• carnivore carnivore
  • eats body fluids
• omnivore omnivore

• Animal Foods
• reptiles
• body fluids
• insects

• Plant Foods
• fruit
• flowers
• sap or other plant fluids

Predation

Known predators of Madame Berthe's mouse lemurs include snakes, such as colubrids and boa manditras , as well as barn owls , Madagascar owls , civets , narrow-striped mongooses and fossas . Their anti-predator adaptations include cryptic fur coloring, agility and preference for protected sleeping sites, such as holes and leaf or vine nests. These nests are often shared with other mouse lemurs.

• Anti-predator Adaptations
• cryptic cryptic

Ecosystem Roles

Because Madame Berthe's mouse lemurs are frugivorous they may contribute to seed dispersal. They also serve as prey for snakes , owls , mongooses , fossas and civets .

• Ecosystem Impact
• disperses seeds

Economic Importance for Humans: Positive

Madame Berthe's mouse lemurs have received attention recently because of their status as the "smallest living primate". This primate, along with the other interesting fauna in the Kirindy Forest, has attracted curious visitors, who can take walking or automobile tours of the area (Kirindy Forest) . Although their diminutive size may attract tourists, this feature is a deterrent for hunters. Likewise, Madame Berthe's mouse lemurs may also be of service to humans by dispersing seeds as a result of their frugivorous diet.

• Positive Impacts
• ecotourism ecotourism

Economic Importance for Humans: Negative

There are no known adverse effects of Madame Berthe's mouse lemurs on humans.

Conservation Status

Madame Berthe's mouse lemurs are considered an endangered species by the International Union for Conservation of Nature and are listed under Appendix I by the Convention of International Trade in Endangered Species of Wild Fauna and Flora. Their habitat is limited to the Menabe region in south-west Madagascar, in approximately a 900 square kilometer area that is being reduced and threatened by slash-and-burn agriculture and illegal logging. Between 1985 and 2000, about half of the forested areas in the region were destroyed. With fewer than 7,900 remaining individuals, Madame Berthe's mouse lemurs face a severe threat. However, measures to create a 100,000 ha Conservation Site in Central Menabe, as well as protect the Kirindy Forest through the establishment of a strict conservation zone have been proposed.

Additional Links

Encyclopedia of Life

Contributors

Chelsea Lane (author), Yale University, Eric Sargis (editor), Yale University, Leila Siciliano Martina (editor), Texas State University.

References

Andrainarivo, C., V. Andriaholinirina, A. Feistner, T. Felix, J. Ganzhorn, N. Garbutt, C. Golden, B. Konstant, E. Louis Jr., D. Meyers, R. Mittermeier, A. Perieras, F. Princee, J. Rabarivola, B. Rakotosamimanana, H. Rasamimanana, J. Ratsimbazafy, G. Raveloarinoro, A. Razafimanantsoa, Y. Rumpler, C. Schwitzer, U. Thalmann, L. Wilmé, P. Wright. 2012. "IUCN Red List of Threatened Species" (On-line). Microcebus berthae . Accessed March 13, 2013 at http://www.iucnredlist.org/details/41573/0 .

Czaplewski, N., J. Ryan, T. Vaughan. 2011. Mammalogy . Sudbury, MA: Jones and Bartlett Publishers.

Dammhahn, M., P. Kappeler. 2008. Comparative Feeding Ecology of Sympatric Microcebus berthae and M. murinus . International Journal of Primatology , 29/6: 1567 - 1589.

Dammhahn, M., P. Kappeler. 2013. Seasonality and Behavioral Energy Strategies in Microcebus berthae and M. murinus . Pp. 215-223 in Leaping Ahead : Advances in Prosimian Biology . New York, NY: Springer New York.

Dammhahn, M., P. Kappeler. 2008. Small-scale coexistence of two mouse lemur species ( Microcebus berthae and M. murinus ) within a homogeneous competitive environment. Oecologia , 157/3: 473–483.

Dammhahn, M., P. Kappeler. 2005. Social System of Microcebus berthae , the World’s Smallest Primate. International Journal of Primatology , 26/2: 407-435. Accessed March 14, 2013 at http://link.springer.com/article/10.1007%2Fs10764-005-2931-z?LI=true .

Gilissen, E., M. Dhenain, J. Allman. 2001. Brain Aging in Strepsirhine Primates. Pp. 421-431 in Functional Neurobiology of Aging . Massachusetts: Academic Press.

Gron, K. 2009. "Primate Info Net" (On-line). Mouse lemur ( Microcebus ) Taxonomy, Morphology, & Ecology. Accessed March 12, 2013 at http://pin.primate.wisc.edu/factsheets/entry/mouse_lemur/taxon .

Radespiel, U. 2007. Ecological Diversity and Seasonal Adaptations of Mouse Lemurs ( Microcebus spp.). Pp. 211-234 in Lemurs: Ecology and Adaptation . New York, NY: Springer US.

Schwab, D., J. Ganzhorn. 2004. Distribution, Population Structure and Habitat Use of Microcebus berthae Compared to Those of Other Sympatric Cheirogalids. International Journal of Primatology , Vol. 25 Issue 2: 307-330.

2013. "ARKive" (On-line). Madame Berthe’s mouse lemur ( Microcebus berthae ). Accessed March 14, 2013 at http://www.arkive.org/madame-berthes-mouse-lemur/microcebus-berthae/#habitat .

2008. "Kirindy reserve, Madagascar" (On-line). Accessed March 16, 2013 at http://www.wildmadagascar.org/conservation/parks/Kirindy.html .