Verreaux’s sifaka is a diurnal lemur that typically inhabits tropical dry lowland and montane forest (from sea level to 1,300 m), including spiny bush, brush-and scrub thickets, and riparian forests (Sussman et al., 1987), but it is also known from humid forests at low altitudes (Rasoarimanana, 2005). It tends to live in small- to medium-sized multi-male groups that range from 2–14, but average 5–6 individuals (Jolly, 1966; Richard, 1974a, 1985). Females appear to be dominant over males. Home ranges may exceed 10 ha but are often very much smaller (Richard et al., 1993; Carrai and Lunardini, 1996, Raharivololona and Ranaivosoa, 2000). Core areas of overlapping home ranges are defended against neighboring sifaka groups (Benadi et al., 2008). Population densities have been estimated at 47 individuals/km2 in the degraded forests of Belaoka, at 150–200 individuals/km2 in Berenty (Jolly et al., 1982b; O’Connor, 1987), and at 400–500 individuals/km2 at Antserananomby (Sussman, 1974).
The diet is seasonally variable but consists principally of leaves, fruit, and flowers. Leaves are the most important food item during the dry season and fruit during the wet season, at which time this sifaka also appears to use fewer plant species (Richard, 1977). Most seeds consumed are destroyed, meaning that this species is at least partly a seed predator (Ralisoamala, 1996). The survival of Verreaux’s sifaka in Didiereaceae forest suggests that it does not need to drink and can survive severe drought (Jolly, 1966). Richard (1974b) suggested that water may be obtained during the dry season by eating the bark and cambium of Operculicarya decaryi.
The ability of this sifaka to leap from trunk to trunk of spiny, cactus-like plants of the family Didiereaceae, such as Alluaudia ascendens and Alluaudia procera, is one of the most spectacular wildlife phenomena to be observed in Madagascar. These tall thin plants are covered with very hard sharp spines, yet the sifakas are able to leap from one trunk to the next with apparently no concern and without sustaining any injuries. On the ground, Verreaux’s sifaka moves bipedally, bounding on its hindlimbs, usually sideways, with its arms raised above its head. This is a very different spectacle from leaping between the spiny trunks of Alluaudia, but it is equally impressive and has become one of the best known and most appealing symbols of Madagascar’s wildlife.
The age at which sexual maturity is reached varies with habitat. For example, in the spiny forests of Beza-Mahafaly, fewer than half the females have reproduced by six years of age (Richard et al., 2002), whereas at Berenty three-year-old females are routinely seen with newborns (Jolly, 1966). Breeding is seasonal. Mating occurs in January and February, with births occurring 162–170 days after conception (Richard, 2003). A single dominant male monopolizes paternity in each group in Kirindy (Kappeler and Schäffler, 2008), whereas paternity by extra-group males is common in the Beza-Mahafaly population (Lawler et al., 2003). Infants ride on their mother’s belly until about three months of age, at which point they shift to her back. They are almost completely independent at six months (Jolly, 1966). These sifakas sometimes fall victim to the fossa (Cryptoprocta ferox) and the Madagascar harrier-hawk (Polyboroides radiatus) (Rasoloarison et al., 1995; Karpanty and Goodman, 1999); they have specific alarm calls for the latter (Fichtel and Kappeler, 2002). Individuals also occasionally fall prey to the large Madagascar ground boas (Acrantophis madagascariensis, Acrantophis dumerili) when they descend from the trees (L. A. de Roland, pers. comm.).
