Illustration by Stephen D. Nash
Source: Lemurs of Madagascar
(with permission from Conservation International)
All Propithecus are relatively large-bodied, and diurnal. They are short-faced, and have extremely long legs relative to the trunk and the arms, preferring vertical postures that often involve clinging to vertical tree trunks. Much of their locomotion consists of leaping between such vertical supports, propelled by the power of the long hind limbs. However, in terminal tree branches a wide variety of suspensory postures is adopted, particularly in the search for food. On the ground they bound along in an upright position on their hind limbs.
Illustration by Stephen D. Nash, Conservation International
Three species of Propithecus are currently recognized. Two, P. verreauxi and P. diadema, are widely distributed and differentiated into several subspecies. P. verreauxi is a relatively small-bodied species (under 4 kg on average) readily identified by its raucous "si-fak!" call. the third species, P. Tattersalli, is monotypic and has a very restricted distribution in northern Madagascar.
The fur of Verreaux's sifaka is predominantly white, with the top of the head black or chocolate brown. The ears are white, slightly tufted and only moderately prominent. Silver gray or goldish tints may exist on the back and flanks, and the base of the tail. A reddish-brown gland is visible at the base of the throat in males. The mean weight for four captive animals was 3.4 kg, both sexes being of similar size (Kappeler, 1991). P. v. verreauxi is impossible to confuse with other lemurs in its range.
Verreaux's sifaka is found in the remaining forests of southern and southwestern Madagascar, from the Tsiribihina River east to the area a little to the west of Fort-Dauphin (=Tolagnaro), with the eastern limit apparently being the dry portion (Parcels 2 and 3) of the Andohahela Nature Reserve. It has the widest distribution of the four P. verreauxi subspecies, and indeed of all Propithecus taxa.
Illustration by Stephen D. Nash
Photo by Anthony C. Brewer
P. v. verreauxi is a diurnal vertical clinger and leaper, living in small, mostly multimale groups of 2-12 individuals, averaging 5 (Jolly, 1966; Richard, 1974, 1985). Richard (1974) suggests that these are less reproductive units that they are semi-permanent foraging parties. Females appear to be dominant over males. The suspecies occurs in dry, semi-arid spiny vegetation (Didiereaceae forests), brush-and-scrub thickets and deciduous gallery forests along watercourses, and also has been observed in a small patch of humid forest between Parcels 2 and 3 in the Andohahela Nature Reserve. Home ranges may be 10 ha or more, but are often very much smaller. The diet of P. v. verreauxi consists principally of leaves, fruit and flowers, but is highly variable seasonally. Leaves are the most important food item during the dry season and fruit during the wet season, when this sifaka also appears to utilize fewer plant species (Richard, 1977). 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 (1974) suggests that water may be obtained during the dry season by eating the bark and cambium of Operculicarya decaryi.
Photo by Anthony C. Brewer
The ability of this species to leap from trunk to trunk on members of the catus-like Didiereaceae plant family such as Alluaudia ascendens, is one of the most spectacular wildlife phenomena of Madagascar. These trees are covered with very hard, very sharp spines, yet the sifakas are able to leap among them with abandon, without injuring themselves. How this is actually accomplished remains to be studied, but it is one of the most spectacular lemur behavior patterns. P. v. verreauxi's bipedal locomotion on the ground, consisting of a series of comical kangaroo-like hops and bounds with arms raised over the head, is also a highlight.
Breeding is seasonal, with most births occurring in August and September. Infants ride on their mother's belly until about three months of age, at which point they shift to her back. The are almost completely independent in six months (Jolly, 1966).
Verreaux's sifaka is dependent on Didiereaceae bush and riparian forests. These slow-growing forests are threatened largely by cutting of trunks for house construction, and firewood and charcoal production, problems that become more serious every year. Although hunting of P. v. verreauxi is fady to several of the tribes living in its range (e.g., Antandroy, Mahafaly), it is hunted by others and by immigrants to the region. It is also quite easy to hunt in the open, relatively low bush in which it lives, in contrast to the Propithecus of the eastern rain forest. In the Isalo area, this animal is known as sifaka-bilany or "sifaka of the cooking pot", either because of its popularity as a food item or because of the sooty black appearance of individuals from its part of its range.
There are no population figures available, but a reasonable order of magnitude estimate would be >100,000 (Mittermeier et al., 1992). About two dozen Propithecus verreauxi are reported in captivity in the U.S. and Europe, but the subspecies in question is uncertain (ISIS, 1993).
Due to its widespread distribution, presumed large population and occurence in at least seven protected areas, P. v. verreauxi was given a Low Priority rating (3) in the IUCN/SSC Primate Specialist Group's Lemurs of Madagascar: An Action Plan for their Conservation (Mittermeier, et al.. 1992). However, given the recent information on hunting from Malagasy scientists, it seems to be at higher risk than previously believed. Using the latest IUCN Red List criteria, we place this species in the Vulnerable category.
Mittermeier, R. A., Tattersall, I, Konstant, W. R., Meyers, D. M., Mast, R. B. 1994. Lemurs of Madagascar. Conservation International, Washington, D.C.
Mittermeier, R. A., W. R. Konstant, M. E. Nicoll and O. Langrand 1992. Lemurs of Madagascar: An Action Plan for their Conservation. 1993-1999. IUCN/SSC Primate Specialist Group, Gland, Switzerland.
Richard, A. F. 1974. Patterns of mating in Propithecus verreauxi verreauxi. Pp. 49-74 in: R. D. Martin, G. A. Doyle and A. C. Walker (eds.), Prosimian Biology. Duckworth, London.
Richard, A. F. 1977. The feeding behavior of Propithecus verreauxi. Pp. 71-96 in: T. Clutton-Brock (ed.), Primate Ecology: Studies of Feeding and Ranging Behavior in Lemurs, Monkeys, and Apes. Academic Press, London.
Jolly, A. 1966. Lemur Behavior. University of Chicago Press, Chicago.
Kappeler, P. M. 1991. Patterns of sexual dimorphism in body weight among prosimian primates. Folia Primatologica 57:132-146. Related Web sites:
Conservation International Duke University Primate Center Prosimian Picture Gallery Godric's Lemur Gallery Living Lemurs Madagascar Fauna Group Red-fronted lemurs
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