Diurnal behavior of Lemur mongoz at Ampijoroa, Madagascar.

Lemur mongoz was observed for 28 h between February and July in Ampijoroa, northwestern Madagascar. The animals were diurnal, with peaks of activity in mid-morning and late afternoon. This finding contrasts with other reports that L. mongoz at the same site and somewhat later in the year are nocturnal. Group size was three or four. L. mongoz associated with L. fulvus during group progression and feeding and when giving alarm responses to man. Vocal signals consist of a range of intergrading grunts and shrieks; olfactory signals of apparent scent marking with the anogenital region, forehead, and palms of the hands; visual signals of mainly unritualized body movements and postures. All of these signals are quite similar to signals of L. fulvus.