Verreaux's sifaka is a diurnal, social species existing in groups that are typically 5 members strong (4). These groups are mixed, and females appear to be dominant over males, who are the dispersive sex. The mating system is poorly understood, but in small groups only one female breeds each year. The season occurs in late January and early February and births are 6 months later; during the mating season males may fight between themselves for access to females (6). The single young develops rapidly, initially riding on its mothers belly and moving to her back after a month; young are fully independent at around 6 months of age (6). Groups inhabit home ranges that vary in size depending on the resources available; a core territory within this range is usually defended against neighbouring groups (6).  Sifakas spend the majority of their time in the treetops, travelling via vertical clinging and leaping from one tree to the next (2). This method of locomotion can take them as far as 10 m in one leap (2). To cross open spaces they descend to the ground and adopt what looks like a skipping 'dance' on their hind legs with forearms outstretched for balance (2). The diet varies with season but encompasses a wide range of leaves, fruit, flowers and bark (3). Group members are vigilant for predator attacks, and aerial predators such as the Madagascar harrier-hawk (Polyboroides radiatus) excite different calls than those for predators on the ground (6).

Verreaux's Sifaka is a large long-tailed lemur with creamy white fur, a dark brown crown, and white tufted ears. Powerful hind limbs and large hands and feet allow sifakas to leap from tree trunk to tree trunk in a type of locomotion called vertical clinging and leaping.

Verreaux's sifaka is a large lemur; the species is split into 4 subspecies each of which has a distinctive appearance. All members of this species have lustrous creamy white fur but they differ significantly in other markings (6). Verreaux's sifaka (Propithecus verreauxi verreauxi) has a dark brown crown and white tufted ears, in some males the upper chest may also have a reddish-brown tinge, and the face and muzzle of both sexes are very dark (6). Coquerel's sifaka (P. v. coquereli) sports deep maroon thighs and arms, and the colour also extends across the chest. The face is black although a patch of white fur extends down the bridge of the nose; the ears are also black (6). Decken's sifaka (P. v. deckeni) is all white although the fur may sometimes have a golden tinge; the face is black and has a more rounded shape (6). The crowned sifaka (P. v. coronatus) gains its name from its dark chocolate-brown head and throat. The upper body has a golden sheen and the black face is squarer than those of the other subspecies (6). All 4 sifakas have a typical body plan with long, powerful hindlimbs and large hands and feet, allowing them to leap from tree to tree in their arboreal habitat (4). The tail of this species is particularly long and may be used for balance. Sifakas earn their common name from their 'shifak' sounding alarm call (5).

This species is endemic to the island of Madagascar. The Tsiribihina River is believed to be the northern limit of the range, ranging as far as Tolagnaro and the Andohahela National Park in the south-east. Sea level to 1,300 m (Mittermeier et al. 2008).

Verreaux's sifakas are found in the western and southwestern regions of Madagascar.

Biogeographic Regions: ethiopian (Native )

Other Geographic Terms: island endemic

Verreaux's sifaka is endemic to Madagascar and the 4 subspecies occur in apparently isolated and distinct ranges in the south and west of the island (2). Coquerel's sifaka has the northernmost distribution along the northwest coast; next is the crowned sifaka, the most endangered of the 4 subspecies and inhabiting the smallest range (8). Decken's sifaka occurs in a band in the west of the country and it is possible that in its northern limit this species is sympatric with the crowned sifaka (6). P. v. verreauxi has the widest distribution of any of the sifakas of Madagascar and is found in the remaining forests in the south and southwest of the island, and west to the Tsiribihina River (6).

Verreaux's sifakas have distinct coloration with white fur and a hint of yellow contrasting their hairless, black face. Their hands and feet are also black. They have a long tail that ranges from 43 to 56 cm in length, roughly the same length as their body (45 to 55 cm). Verreaux's sifakas are not sexually dimorphic, as both males and females weigh between 3 and 7 kg.

Range mass: 3 to 7 kg.

Range length: 45 to 55 cm.

Other Physical Features: endothermic ; homoiothermic; bilateral symmetry

Sexual Dimorphism: sexes alike

Average basal metabolic rate: 3.738 W.

Habitat and Ecology

Systems

• Terrestrial

Verreaux's sifakas are primarily arboreal and are found in deciduous and evergreen forests. However, they are widespread and can also be found in wet and dry habitats throughout southwest Madagascar.

Habitat Regions: tropical ; terrestrial

Terrestrial Biomes: forest ; rainforest ; scrub forest

This species is characterized by four distinct subspecies that occur in apparently isolated and distinct ranges in the southern and western parts of Madagascar. Verreaux's Sifakas prefer habitats with large trees in various forest types from dry, spiny deciduous woodlands to evergreen forests.

Inhabits spiny and dry deciduous forests (2).

Verreaux's sifakas are herbivorous and feed primarily on leaves, bark, and flowers. When abundant, fruit may also be incorporated into their diet. Nutrition levels directly coincide with season and rainfall amounts, with food of higher nutritional value being most abundant during the wet season.

Plant Foods: leaves; wood, bark, or stems; fruit; flowers

Primary Diet: herbivore (Folivore , Lignivore)

Verreaux’s sifakas are an important prey item for fossas (Cyptoprocta ferox), stray dogs (Canis lupus familaris), and harrier hawks (Polyboroides radiatus). Also, they are strict herbivores and considered to be important seed dispersers.

Ecosystem Impact: disperses seeds

Verreaux's sifakas commonly use alarm calls to warn group members of the presence of a predator. Different alarm calls are given for aerial (harrier hawk, Polyboroides radiatus) and terrestrial predators, which includes fossas (Cyptoprocta ferox) and stray dogs (Canis lupus familaris). Alarm calls are performed by males and females of all ranks in the social hierarchy and are thought to be most effective in group settings. As group size increases the number of individuals able to spot potential predators increases. As a result, group cohesion is an important aspect of deterring predators. It is also thought that large groups are able to intimidate potential predators more easily than small groups.

Known Predators:

• fossas (Cyptoprocta ferox)
• harrier hawk (Polyboroides radiatus)
• domestic dogs (Canis lupus familaris)

Verreaux's sifakas communicate over long distances via clear, deep barks. Barks sound similar to the word “sifaka” and are produced only when intruders are nearby. Barks are generally made by the group leader, and if group cohesion is ever threatened by an outsider, growling or barking is produced to ward off intruders.

Scent marking is an additional form of communication used by Verreaux's sifakas. It serves multiple purposes including marking territory, making one's presence known (specifically females in estrus), claiming food or territory, attracting mates, and may be used during non-physical competition. Scent marking is a versatile and important way of communicating in Verreaux's sifakas.

Communication Channels: acoustic ; chemical

Other Communication Modes: scent marks

Perception Channels: visual ; acoustic

This species is primarily a frugivore or fruit eater, but its diet changes with the seasons. In the rainy season, Verreaux’s Sifakas eat more fruits and flowers, whereas in the dry season they consume mainly dead wood, bark, and leaves – a habit which may help them absorb more water.

Verreaux's sifaka is a social species living in groups of 3-13 members. These groups are mixed and females appear to be dominant over males. Breeding females give birth to a single black, hairless offspring which clings to its mother's belly for 3 to 4 weeks, before moving to her back.

Little is known about the lifespan of Verreaux's sifakas in the wild, as the residents of Madagascar rarely come into contact with them. Studies have found that they have a surprisingly low parasitic load, which may result in increased lifespan relative to other closely related primates. The average lifespan of captive Verreaux's sifakas is 18 years with a recorded maximum of 23.5 years.

Range lifespan

Status: captivity: 23.5 (high) years.

Average lifespan

Status: captivity: 18 years.

Average lifespan

Status: captivity: 18 years.

Average lifespan

Sex: male

Status: captivity: 20.6 years.

Average lifespan

Status: captivity: 18.2 years.

Average lifespan

Status: captivity: 18.0 years.

Average lifespan

Sex: female

Status: captivity: 18.2 years.

Maximum longevity: 30.5 years (captivity) Observations: One male of the *coquereli* subspecies lived 30.5 years at the Duke University Primate Center (Richard Weigl 2005). Infant survival of old females drops, but a decline in fertility has been reported in some of the oldest females (Pochron et al. 2004).

Verreaux's sifakas form social hierarchies, which are subject to change during the mating season as females only breed with dominant males. Subordinate males challenge dominant males, often resulting in intense competition and fighting.

Verreaux's sifakas scent mark as a form of communication. Females scent mark to get the attention of males. Subordinate males scent mark to get the attention of females, and dominant males scent-mark to claim territory. Scent-marking often results in conflict among males.

Mating System: polygynous

Verreaux's sifakas breed from late January through March. Following implantation, gestation lasts 130 to 141 days. Typically, mothers give birth to only one offspring per year, which occurs between June and September. Average birth weight is 40 g. Mothers carry young close to their abdomen and chest for the first 2 to 3 months of the offspring's life. At about 3 months old, young move to their mothers back until they reach 5 to 6 months of age and are weaned at about six months. Young sifakas reach adult size at 21 months and are sexually mature by two and a half years old.

Breeding interval: Once a year

Breeding season: January to March

Average number of offspring: 1.

Range gestation period: 4 to 5 months.

Average birth mass: 40 g.

Average weaning age: 180 days.

Average time to independence: 2.5 years.

Average age at sexual or reproductive maturity (female): 2.5 years.

Average age at sexual or reproductive maturity (male): 2.5 years.

Key Reproductive Features: iteroparous ; seasonal breeding ; gonochoric/gonochoristic/dioecious (sexes separate); viviparous

Average birth mass: 72.25 g.

Average number of offspring: 1.

Average age at sexual or reproductive maturity (male)

Sex: male: 912 days.

Average age at sexual or reproductive maturity (female)

Sex: female: 912 days.

Verreaux's sifakas live in social groups and young are cared for by adults. A mother's position in the social hierarchy affects the social status of her young and parental care continues until young reach full size at about 21 months. Females stay with the group, while males either stay with the group or leave to form their own. Mothers carry newborn sifakas near their chest and abdomen for the first 2 to 3 months after birth and then on her back until offspring reach about 6 months of age.

Parental Investment: male parental care ; female parental care ; post-independence association with parents; extended period of juvenile learning; maternal position in the dominance hierarchy affects status of young

Year Assessed

Assessor/s

Reviewer/s

Justification

History

• 2000
  Vulnerable
• 1996
  Vulnerable
• 1990
  Vulnerable
  (IUCN 1990)

Verreaux's sifakas are rapidly losing their natural habitat. Due to slash-and-burn agriculture, the deciduous forests of Madagascar are severely threatened. Additionally, Malagasy forests have been subjected to commercial logging, overgrazing by livestock, and charcoal manufacturing. Fortunately, captive breeding has been successful in Verreaux's sifakas, which, according to the IUCN Red List, are considered "vulnerable".

US Federal List: no special status

CITES: appendix i

State of Michigan List: no special status

IUCN Red List of Threatened Species: vulnerable

IUCN Red List Status: VULNERABLE

Classified as Vulnerable (VU - A2cd) on the IUCN Red List 2004 (1), and listed on Appendix I of CITES (7). Subspecies: Verreaux's sifaka (Propithecus verreauxi verreauxi) classified as Vulnerable (VU-A2cd); Coquerel's sifaka (P. v. coquereli) classified as Endangered (EN - A2c, B1+2bc); Decken's sifaka (P. v. deckeni) classified as Vulnerable (VU - A1c); crowned sifaka (P. v. coronatus) classified as Critically Endangered (CR - B1+2bc, C2a) (1).

Population

Population Trend

Major Threats

These engaging lemurs are threatened by habitat destruction throughout their range. The dry deciduous forests of the west are being cleared for timber extraction, firewood and charcoal production and resulting fragments of habitat are also at risk from deliberate fires (6). Hunting of the species is a taboo in some areas but does still occur in others and is made easier by the relatively open habitat (6). Of the 4 subspecies, the crowned sifaka is the most endangered and population estimates vary between just 100 and 1,000 individuals (1).

Conservation Actions

Verreaux's sifaka is protected from international trade by its listing on Appendix I of the Convention on International Trade in Endangered Species (CITES) (1). Individuals have been successfully bred in captivity (4), and there are estimated to be around 24 of these sifakas currently held in captivity in the United States and Europe, although which subspecies these represent is uncertain (8). Within Madagascar, P. v. verreauxi is known to occur in at least 7 protected areas, Coquerel's and Decken's sifakas in at least 2, but at present the crowned sifaka has not been confirmed from any of the protected areas within its range (6). More data is urgently needed on the distribution and natural ecology of the lesser-studied subspecies and protected reserves are vital to preserve the remaining, if fragmented, habitat of the species as a whole.

There are no known adverse effects of Verreaux's sifakas on humans.

Verreaux’s sifakas are the most extensively studied of the Malagasy prosimians and have been the subject of a wide range of research topics. These topics include, but are not limited to bipedalism in mammals, the evolution of social hierarchies, the causes and consequences of female dominance in mammals, the evolution and ecological consequences of male dimorphism, the causes and consequences of decreased parasitic loads, and the evolution of characteristics that are necessary for living in the variable environments of Madagascar. Verreaux's sifakas are also an important component of the unique Madagascar ecosystem, which attracts tourists from around the globe.

Positive Impacts: ecotourism ; research and education