Madame Berthe's Mouse Lemur - Behaviour

Behaviour

Microcebus berthae are typically solitary foragers, but are not without social interaction with other members of their species. About half the time, they sleep alone. Otherwise, they can be found sleeping next to one or more lemurs, with no preference or prejudice to close relatives or members of the opposite sex. Be it alone or in a group, Microcebus berthae tend to sleep in leaf nests in trees, or without a nest, in hole-like structures. On occasion, the paths of two members of the species may cross, leading to different kinds of social encounters. Some encounters involve bouts of mutual grooming, sex, or huddling (an activity which can last up to 23 minutes). Other meet-ups between lemurs might include chasing, biting and grabbing. Overall, male-male and female-female interactions do not differ qualitatively. Unlike other species of lemur, Microcebus berthae do not hibernate during the cold-dry season, instead compensating for food scarcity with a larger than average home range.

In a population of Microcebus berthae, males significantly outnumber females. Despite there being no sexual dimorphism in skull length, canine height, or tail length, the average female is larger than the average male in head-body length and head width. Average body mass, while relatively equal during mating season, becomes smaller for males in the duration of time excluding mating season. Males have a home range of about 4.92 hectares, while females have a home range of about 2.50 hectares. Females tend to remain in a home range that is close to, or includes their place of birth. This is the opposite of males, who tend to disperse from their place of birth. The home ranges of individual lemurs tend to overlap with each other, with female home ranges overlapping with that of one or two other females, and male home ranges overlapping with that of up to 9 other males.

Compared to other lemurs, M. berthae is more similar to in social systems to the Microcebus murinis than the ]. In other words, Madame Berthe's mouse lemur is sexually promiscuous rather than monogamous. The range in distance of the males in the species was larger than that of the females in both Microcebus species before and after the mating seasons. Research has also been done on the distribution of sleeping sites, as well as numerical data on the testes size and the presence of vaginal plugs in the species. Concluding from capture rates and physiological proof, there is no evidence that M. berthae has a hibernation season, therefore increasing the chances of sexual activity within the species.