The nocturnal and cryptic lifestyle of the hairy-eared dwarf lemur renders it a difficult species to detect (4), and thus little is known about its biology and ecology. Until 1990, when this species was rediscovered near Mananara, knowledge of this animal was confined to just five museum specimens, of unclear and unreliable origin, and it was believed to be extinct (4). This arboreal primate constructs nests of fresh leaves in small holes of dead or living trees, usually three to five meters above ground (2) (4). During the cold season, which extends from early May to mid-October, it is thought to reduce activity, making detection even more difficult (2) (12) (13). Hairy-eared dwarf lemurs have been encountered in groups of two to six individuals, most likely one or more adult pairs with their offspring (2) (5), and it feeds upon flying insects, gum, new leaves and small fruits (2) (5) (12).