Coquerel’s mouse lemur is nocturnal, and active all year round. This tiny primate is arboreal, and feeds on fruit, flowers and gums, as well as small animal prey such as insects, spiders, frogs, lizards, small birds, and eggs. During the dry season it also feeds on sweet secretions of homopteran larvae to supplement its diet. Interestingly, most activity is carried out alone. Gum sites and animal prey can only be fed on by one animal at a time, which necessitates solo feeding. To facilitate its ability to forage at night, this animal’s night vision is improved by a layer of light reflecting crystals behind the retina: a common adaptation in nocturnal animals (4).
This species is well adapted for its nocturnal lifestyle. Coquerel's mouse lemur feeds in the dark to avoid being seen by predators such as birds, and are careful not to be seen or heard. They communicate and coordinate activities using acoustic and olfactory signals, including ultrasound. By day they hide in spherical nests constructed from interwoven vines, twigs and leaves (2). The use of these nests reveals that this species’ social relationships are complex as individual adults sleep alone, though adult females occasionally sleep in pairs (4).
The female Coquerel's mouse lemur occupies a home range that overlaps with those of close relatives and, as with many mammals, males have home ranges that are larger than those of the females, especially during the breeding season. Recent research has revealed the breeding season is in October, during which the males’ testes become dramatically enlarged. Male individuals also emit a shrill call as part of the mating display and females advertise their onset of oestrous with loud calls. These factors, coupled with the increase in a male’s home range size during breeding season, indicate that competition between males for females is intense, and that this species is promiscuous (2) (4). The gestation period lasts for 86 to 89 days, and one to four (usually two) young are born in a nest (5). Even after juveniles leave their mother, they remain in contact with vocal calls for some time (4). Sexual maturity is reached after 18 months and, in healthy forests, populations can breed successfully, producing densities of up to 385 individuals per km² (2).