As originally described, M. rufus is reported to occur at high densities in tropical moist lowland and montane forests, and sometimes in adjacent secondary forest formations, bamboo forests, old plantations, and even Eucalyptus groves, from sea level to 2,000 m (Ganzhorn, 1987a, 1988; Duckworth et al., 1995; Atsalis, 1999a, 2000). It is omnivorous, subsisting mainly on fruits, but also flowers, insects, gums, and occasionally young leaves (Atsalis, 1998a, 1998b). Fruit of the mistletoe Bakerella, which has a high fat and high fiber content, seems to be a particularly important dietary component, and beetles were the insects most frequently eaten (Atsalis, 1999b). This species is usually seen feeding in shrubs and low trees. Fat storage in the tail seems to be less important than in M. murinus.
Rufous mouse lemur ecology and social behavior have been studied in Ranomafana (Atsalis 1999a, 1999b, 2000). Individuals scent mark with urine and feces, a behavior that helps delimit ranges and communicate presence to conspecifics (Tattersall, 1982). This species sleeps in tree holes and leaf nests during the day, and has even been observed to use old bird’s nests (Martin, 1973; Pollock, 1979b). Predators include the ring-tailed mongoose (Galidia elegans), Madagascar Harrier-hawk (Polyboroides radiatus), owls, dogs and cats (Goodman et al., 1993c; Langrand and Goodman, 1996).
Male territories often overlap those of two or more females (Atsalis, 1999a). Mating takes place in September and October, during which time the male’s testes increase significantly in size. One to three young are born following a two-month gestation. During the austral winter, from May through September, most females and some males enter a state of torpor, losing from 5 to 35 g in body weight (Atsalis, 1998a, 1998b, 1999a). Males begin becoming active again in August, while females remain torpid for one or two more months.
It should be noted that many of the studies of “Microcebus rufus,” were actually of some of the newly-described taxa, expecially those by Ganzhorn at Analamazaotra Special Reserve (at Andasibe), which are now known to refer to M. lehilahytsara.