Diademed sifaka or simpona, simpony or ankomba joby (Propithecus diadema)
The diademed sifaka is one of the mostly widely distributed sifakas . It occurs in primary rainforests and smaller forest fragments at altitudes of 200-800 m throughout much of the eastern Madagascar lowland forests and at altitudes 800- 1,625 m in subhumid montane rainforests. The range extends to at least the Mananara Nord River in the north to the Onive and Mongoro Rivers in the south (11,12). The range is situated between those of the Milne-Edward's and silky sifakas (12). Earlier authors said it occurred between Antainambalana River near Maroantsetra and Mananara Nord River (13). Members of an anomalous outlier population of P. diadema in south central Madagascar show various colour markings, including an all black lemur. DNA analyses have not concluded if this group constitutes a new species.There is a clinal variation between P. diadema and P. edwardsi in the extreme southern portion of the range . Specific locations for sighting the diademed sifaka are Mantadia National Park and in the forests of Tsinjoarivo.
It lives in multi-male/multi-female groups of 2-10 individuals (4). Communication is rich and varied. The sifakas use scent-marking to defend home ranges of 20-50 ha (14). Males scent mark twice as often as females. Scent marking frequency doubles when approaching the territorial boundaries (10,15-17). Vocalizations are used mainly to maintain vocal and chemical communication. Sifakas use tactile communication, in the form of grooming, play, and aggression. This may be very important between mothers and their young, as well as between mates. Sifakas probably use facial expressions, body postures and other visual signals in their communication (18). The sifaka defends the group's territory strongly against other diademed sifakas, but shares territory with red-bellied and common brown lemur. It is thought to traverse the greatest daily path distance relative to other members of its family in its patrolling and foraging, attaining a typical travel distance in excess of 1.6 km a day.
It is thought that the diademed sifaka behaves like the related Milne-Edward's sifaka (2). The sifaka is diurnal and spends almost all its time in trees, being rarely seen on the ground; it is a vertical clinger and lateral leaper through the trees (2). It can achieve lateral aerial propulsion of up to 30 km per hour, due to muscular leg thrusting action pushing off from a vertical tree trunk. Individuals may alight on the ground to search for fallen fruit and to engage in play-fighting; some sifakas eat soil, possibly in an effort to rid themselves of toxins (4).
It is herbivorous, eating mainly verdant leaves, as well as flowers, seeds, fruits, and young shoots from @ 25 species of plants (2) at all levels of the canopy. As a frugivore, it probably helps to disperse seeds. As potential prey items, Individuals of all ages and both sexes may impact predator populations. are subject to predation. Suspected avian predators include Madagascar harrier-hawks and Henst's goshawks. The fossa is an ambush predator. The sifaka gives 2 alarm vocalizations in response to predators. The ground predator call is a "tzisk-tzisk-tzisk" or "kiss-sneeze" when a fossa, Nile crocodile or another terrestrial predator is perceived . The aerial predator call is a "honk-honk-honk" (10,15-17). The sifaka high levels of activity is linked to a diet high in energy content, including a high consumption of two plants containing high concentrations of alkaloids.
Mating occurs between resident males and resident females, with no recorded cases of invading males successfully copulating. The female is probably receptive to mating few days per year. Being dominant, she has the greatest input to mate selection. There is a hierarchy system for mating; it seems that only the dominant male copulates with the females. Submissive males may show aggression and try to keep the dominant male from mating. Copulation occurs in summer (in December and January) and there is usually one offspring per female every 2 years. Gestation period is @ 157-180 days. Births for Milne-Edward's sifaka occur in May and July, but those for other species may occur later in the year (4). Females can produce 1-2 offspring in winter (May-July) every 2 years (10,16). The altricial newborn young weighs @ 145 g. The infant initially clings to its mothers belly before transferring to her back after a month (4). Nursing begins to decrease from the age of 2 months. At 1 year old, suckling during the day ceases. As well as continue until the infant is two years old. In addition to food, the mother provides her young with protection, grooming, and socialization. When the young is 2 years old, its mother's milk does not provide it with a substantial amount of their nutrition. Sexual maturity is reached at 4 years for females and 5 years for males. Sexual maturity is reached at 2-5 years of age; the male matures more slowly than the female. Males disperse, but females stay within their natal group and are the dominant sex in the group (4). Captive sifakas may live beyond 23 years in captivity (18). A wild sifaka may live up to 21 years with no signs of reproductive senescence except a slight increase in mortality with age (19). Dental senescence may occur described in animals over 18 years old. Wild sifakas may be able to live over 27 years in the wild (20).
The diademed sifaka is classified as Critically Endangered on the IUCN Red List and is listed on Appendix I of CITES. In 2002, population estimates for the species ranged from 6,000-10,000 individuals . The primary threat is habitat reduction due to shifting cultivation by native peoples. This threat is also present within designated national parks, where it is hard for the government to enforce national laws protecting habitat. Pressures of overpopulation in central and eastern Madagascar cause many of the rural poor to seek subsistence by seizing forest lands, timber extraction and undertaking slash-and-burn tactics as their initial step in a shifting cultivation system (4). Deliberate fires encroach on the highly- fragmented habitat (4). Returns from such land use are usually meagre, yielding small amounts of charcoal, firewood or grass crop for grazing of zebu (4). Illegal rum production, involving planting sugar cane fields threatens populations in Tsinjoarivo. The species is thought to have undergone a reduction of more than 50% over the past 30 years due primarily to a decline in area and quality of habitat within its range of the species and due to levels of exploitation; the population trend is 'Decreasing'. It is hunted for food, even in protected areas (14). This species occurs in three national parks (Mananara-Nord, Mantadia, and Zahamena), two strict nature reserves (Betampona and Zahamena), and three special reserves (Ambatovaky, Mangerivola, and Marotandrano) (14). Additional populations have been identified in the Andriantantely Classified Forest, Tsinjoarivo Classified Forest, the Marokitay Forest Reserve, and in the unprotected forests of Anosibe, Anjozorobe, Didy, Iofa, Maromiza and Sandranantitra (14). The Tsinjoarivo Classified Forest has already been recommended as a new protected area. In response to threats, several reserves have been established within the last few decades, along with campaigns to educate locals and find better methods of agriculture (10,17,21). This species and other unique plants and animals have stimulated a large amount of ecotourism, helping to bolster the economy of a severely depressed nation (21). This species was represented in a zoological collection at the Duke University Primate Center in Durham, North Carolina, USA.
The diademed sifaka comprised 4 distinct subspecies, which are now classified as separate species (4) and form a tight species group within the Propithecus genus, but all have a distinct range (10). The other 4 species are the Milne-Edwards' sifaka (P. edwardsi), Perrier's sifaka (P. perrieri), golden-crowned sifaka, (P. tattersalli) and silky sifaka (P. candidus). They have luxuriant silky coats and are powerful leapers. They share similar characteristics of gestation length (4 months), age of sexual maturity, female dominance, life expectancy (18 years) and propensity for sunbathing while stretched out on a branch. They differ in colouration and markings, but have black, naked faces and red-orange eyes.
Propithecus diadema, like all lemurs, occurs only in Madagascar. Although all sifakas occur on the eastern side of the island, each of the four described subspecies has a distinct range (Garbutt, 1999).
Biogeographic Regions: ethiopian (Native )
Other Geographic Terms: island endemic
Members of the genus Propithecus reach lengths between 450 and 550 mm, with the tail adding an additional 432 to 560 mm. Propithecus diadema weighs between 5 and 7 kg.
Each subspecies is phenotypically unique. Propithecus diadema diadema is often reported to be the largest extant lemur. These animals have a white head, grey shoulders, tail, and back, and golden limbs. Propithecus diadema edwardsi is almost completely grey/black, with a white back. Propithecus diadema candidus has almost completely white pelage with tints of grey. Propithecus diadema perrieri is completely black. All subspecies have dark naked faces and red-orange eyes.
The only other animals with which these animals might be confused are indris. However, sifakas have a very long tail, which distinguishes them from short-tailed indris.
Range mass: 5 to 7 kg.
Range length: 450 to 550 mm.
Other Physical Features: endothermic ; homoiothermic; bilateral symmetry
Sifakas generally inhabit mid-altitude rainforests. These animals mainly occur at elevations above 800 meters. The range of P. diadema candidus extends into montane rainforest. Rainfall in sifaka habitat is variable, from 2000 to 4000 mm per year, with most rainfall occurring during the summer months (December through March) (Wright, 1995; Garbutt, 1999).
Range elevation: 800 (low) m.
Habitat Regions: tropical ; terrestrial
Terrestrial Biomes: rainforest ; mountains
Habitat and Ecology
It is found in the eastern rainforests, and persists in some smaller forest fragments (down to ~30 ha). The diet consists mainly of ripe fruits, seeds, flowers, and young leaves, their respective proportions varying according to seasonal abundance (Irwin 2008b). Females are sexually receptive for very few days (perhaps only one day) out of the year, sometime between November and January. A single young is born between May and July, after a gestation of 179 days. Individuals may live up to 20 years in the wild. This species is diurnal and arboreal. In one study, these animals spent 49·4% of their time resting, 37·8% feeding, 2·4% in social behaviour, 5·1% moving, and the remainder in other activities. This species has only twice been studied for a significant period of time (by Powzyk at Mantadia and Irwin at Tsinjoarivo). It lives in female-dominated, multi-male/multi -female groups of 2 to 8 individuals, consisting of 1–3 adult females and 1 or 2 adult males, and multiple females may breed within the same group. Exclusive territories of 20–80 ha are maintained by means of scent-marking, although there is little aggression over boundaries. Compared to the sympatric, similar -sized Indri indri, P. diadema spends more time actively patrolling and defending its territories. The mean daily path length of 987– 1629 m for P. diadema can be compared to 774 m for I. indri (Powzyk 1997). Predation by fosa (Cryptoprocta ferox) may be an important threat to this species, especially in fragmented or degraded areas where other prey species may be reduced (Irwin et al. 2009). Males emigrate at age five, often to a neighbouring group; females may either emigrate or remain in their natal group (Mittermeier et al. 2010 and references therein)
Propithecus diadema is herbivorous, eating only leaves, flowers, fruits, and young shoots. Approximately 25 species of plants are consumed in each of the two subspecies that have been studied (P. diadema edwardsi and P. diadema diadema). Propithecus diadema edwardsi has also been seen eating soil, possibly to detoxify plant poisons or to supplement their diet with trace elements (Garbutt, 1999).
Plant Foods: leaves; fruit; flowers
Primary Diet: herbivore (Folivore , Frugivore )
As frugivores, these animals probably help to disperse seeds. As potential prey items, they may impact predator populations.
Ecosystem Impact: disperses seeds
Individuals of all ages and both sexes are subject to predation. No documented cases of predation by reptiles or raptors exist, but suspected avian predators include Madagascar harrier-hawks and Henst's goshawks. The main predators of P. diadema are probably fossas, an ambush predator that takes advantage of any opportunities available.
Two alarm vocalizations are given in response to predators. The ground predator call is a "tzisk-tzisk-tzisk", and the aerial predator call is a "honk-honk-honk" (Wright, 1988, 1995; Garbutt, 1999; Mittermeier, 1994).
- Cryptoprocta ferox
- Polyboroides radiatus
- Accipiter henstii
Life History and Behavior
As in all primate species, communication is rich and varied. Vocalizations are used mainly in maintaining group cohesion. Two alarm vocalizations are given in response to predators. The ground predator call is a "tzisk-tzisk-tzisk", and the aerial predator call is a "honk-honk-honk" (Wright, 1988, 1995; Garbutt, 1999; Mittermeier, 1994).
Scent marking is common, and males scent mark twice as often as females. Scent marking frequency doubles when approaching the territorial boundaries (Wright, 1988, 1995; Garbutt, 1999; Mittermeier, 1994).
In addition to vocal and chemical communication, these animals use tactile communication, in the form of grooming, play, and aggression. Tactile communication is likely to be of high importance between mothers and their offspring, as well as between mates.
Although not specifically reported for these animals, we may assume that, like other diurnal primates, they use visual signals in their communication also. These include but are not limited to facial expressions and body postures (Nowak, 1999).
Communication Channels: visual ; tactile ; acoustic ; chemical
Other Communication Modes: scent marks
Perception Channels: visual ; tactile ; acoustic ; chemical
The longevity of this species has not been reported. However, an individual of another species in the genus, Propithecus verreauxi, is reported to have lived beyon 23 years on captivity (Nowak, 1999). It is likely that P. diadema is capable of reaching similar ages.
Lifespan, longevity, and ageing
Our current understanding of the mating system of this species is limited. Mating occurs between resident males and resident females, with no recorded cases of invading males successfully copulating. There is a hierarchy system for mating, and it seems that only the dominant male copulates with the females. Submissive males may show aggression and attempt to keep the dominant male from mating.
Mating System: polygynous
The best data on reproduction exists for P. diadema edwardsi, but data for other subspecies suggest that they are similar. Copulations occur in summer, in the months of December and January. Gestation period is around 180 days (approximately six months). Females give birth to one or two offspring in the winter months (May, June, July).
Offspring are carried by their mother. The young may nurse up to the age of 2, although by this time, mother's milk does not provide them with a substantial amount of their nutrition. Sexual maturity is reached at four years for females and five years for males. Birth rates are approximately 0.5 offspring per female per year (Wright, 1995; Garbutt, 1999).
Breeding interval: Females are able to produce offspring every two years.
Breeding season: Copulations occur in summer, in the months of December and January
Range number of offspring: 1 to 2.
Average gestation period: 180 days.
Range weaning age: 24 (high) months.
Average age at sexual or reproductive maturity (female): 4 years.
Average age at sexual or reproductive maturity (male): 5 years.
Key Reproductive Features: iteroparous ; seasonal breeding ; gonochoric/gonochoristic/dioecious (sexes separate); sexual ; fertilization ; viviparous
Average birth mass: 145 g.
Average gestation period: 157 days.
Average number of offspring: 1.
Average age at sexual or reproductive maturity (male)
Sex: male: 913 days.
Average age at sexual or reproductive maturity (female)
Sex: female: 1186 days.
Offspring initially cling to the mother's belly, switching to her back at around one month of age. Nursing begins to decrease from the age of two months, although the process of weaning is protracted. At six months of age, less than half of the offspring's diet consists of the mother's milk. At one year of age, suckling during the day ceases. Suckling during the night, however, may continue until the infant is two years old.
In addition to food, the mother provides her young with protection, grooming, and socialization.
The role of males in parental care has not been described.
Parental Investment: altricial ; pre-fertilization (Provisioning, Protecting: Female); pre-hatching/birth (Provisioning: Female, Protecting: Female); pre-weaning/fledging (Provisioning: Female, Protecting: Female); pre-independence (Protecting: Female); extended period of juvenile learning
Both P. diadema candidus and P. diadema perrieri are given IUCN critically endangered status. All subspecies are threatened by habitat destruction. This occurs mainly in the form of slash-and-burn agriculture, but also as timber extraction. Most are also hunted for food, even in protected areas. All subspecies occur in at least one protected area.
In response to these threats, several reserves have been established within the last few decades. Also, campaigns to educate locals and find better methods of agriculture have been persued (Wright, 1992; Mittermeier, 1994; Garbutt, 1999).
US Federal List: endangered
CITES: appendix i
IUCN Red List of Threatened Species: endangered
IUCN Red List Assessment
Red List Category
Red List Criteria
A population reduction of ≥80% is suspected to be met in the future (over a three generation time period of 45 years). This is based on a continuing decline in area, extent and quality of habitat due to slash-and-burn agricultural practices and timber extraction as principal threats, planting of sugar cane fields and destructive utilisation of sifaka food trees in some areas, in addition to exploitation through unsustainable hunting pressure. Based on these premises, the species is listed as Critically Endangered.
- 2000Critically Endangered
- 1990Endangered(IUCN 1990)
This species is rare. It occurs only at very low densities wherever it is found: at Tsinjoarivo densities of 7 individuals/km2 were recorded in less-disturbed, continuous forest, with higher local densities in some smaller fragments (Irwin 2008a). Population figures are in decline due to habitat destruction and hunting.
Continued destruction of rain forest habitat in eastern Madagascar due to slash-and-burn agricultural practices and timber extraction is the principal threat to this sifaka’s survival, although hunting for food also can have a very serious impact on remaining populations, even within existing protected areas (Mittermeier et al. 2010). Furthermore, illegal rum production, necessitating the planting of sugar cane fields and destructive utilization of sifaka food trees, is a threat to populations in Tsinjoarivo (Irwin and Ravelomanantsoa 2004).
This species is listed on Appendix I of CITES. This species occurs in three national parks (Mananara-Nord, Mantadia, and Zahamena), two strict nature reserves (Betampona and Zahamena), and three special reserves (Ambatovaky, Mangerivola, and Marotandrano) (Mittermeier et al. 2010). Additional populations have been identified in the Andriantantely Classified Forest, Tsinjoarivo Classified Forest, the Marokitay Forest Reserve, and in the unprotected forests of Anosibe an’ala, Anjozorobe, Didy, Iofa, Maromiza and Sandranantitra (Mittermeier et al. 2010). The Tsinjoarivo Classified Forest has already been recommended as a new protected area. As of 2012 this species was not represented in captivity.
Relevance to Humans and Ecosystems
There is no known negative economic effect of this species on humans.
The existence of this rare and endemic species, as well as the rest of Madagascar's unique flora and fauna, has stimulated a large amount of ecotourism for the area. This, along with the establishment of several reserves in Madagascar's remaining forests, has helped to bolster the economy of a severely depressed nation (Wright, 1992).
Positive Impacts: ecotourism
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The diademed sifaka (Propithecus diadema), or diademed simpona, is an endangered species of sifaka, one of the lemurs endemic to certain rainforests in eastern Madagascar. This species is one of the world's largest living lemurs, with a total adult length of approximately 105 centimetres (41 inches), half of which is tail. Russell Mittermeier, one of the contemporary authorities on lemurs, describes the diademed sifaka as "one of the most colorful and attractive of all the lemurs", having a long and silky coat. P. diadema is also known by the Malagasy names simpona, simpony and ankomba joby. The term "diademed sifaka" is also used as a group species designation formerly encompassing four distinct subspecies.
P. diadema is readily distinguished from all the other lemur species by its characteristic markings and large physical size. Its entire coat is moderately long, silky and luxuriant. The long white fur encircling his muzzle and covering its cheeks, forehead and chin, engenders the "diadem" or crown appearance. Its eyes are a reddish-brown, the muzzle is short, and the face is bare with colourisation of darkish gray to jet black. The crown fur is also quite black and often extends to the nape of the neck. The upper back and shoulder fur are slate grayish, although the lower back is lighter in colour attaining a silvery quality. Flanks and tail are a paler gray, sometimes even white, as is the case for ventral fur. Hands and feet are entirely black, while arms, legs and base of tail are a yellowish-golden hue. Only the male is endowed with a large cutaneous gland at the exterior center of the throat, which feature is typically reddish-brown.
Range and habitat
The diademed sifaka is one of the mostly widely distributed member of the Propithecus genus, although definitive mapping of its range has not been conducted. Occurrence is at altitudes of 200 to 800 metres (656 to 2,624 feet) throughout much of the eastern Madagascar lowland forests and altitudes 800 to 1,550 metres (2,624 to 5,084 feet); in portions of the Madagascar subhumid forests. These two biomes have been designated as a Global 200 ecoregion, one of the world's most significant regions for conservation. Geographically the range extends to at least the Mananara River in the north to the Onive and Mongoro Rivers in the south. One set of researchers has recorded a clinal variation between Propithecus diadema and Propithecus edwardsi in the extreme southern portion of the range. As with all Indriidae, this species and its entire genus have evolved on the island of Madagascar independent of other mainland African species.
An anomalous outlier population of P. diadema has been discovered in south central Madagascar; the members of this population exhibit an array of different colour markings, including at least one observation of an all black lemur. DNA analyses have not resulted in consistent results as to whether this group of individuals should constitute a new species. Scientists have decided to classify this outlier group as P. diadema until further research warrants designation of a separate species.
The diademed sifaka forms groups typically of two to ten individuals, which may include multiple male and female adults. Each troop defends an exclusive home territory of 25 to 50 hectares (62 to 125 acres) using perimeter scent territorial marking by both the males and females. Although the diademed sifaka defends the group's territory strongly against other members of their same species, it will share territory with other species such as the Red-bellied Lemur and the Common Brown Lemur. P. diadema is thought to traverse the greatest daily path distance relative to other members of its family in its patrolling and foraging, attaining a typical travel distance in excess of 1.6 kilometres (one mile) per day. To accomplish this it consumes a diet high in energy content and diverse in plant content, each day consuming over 25 different vegetative species. This diurnal lemur further diversifies its diet by consuming not only fruits, but certain flowers, seeds and verdant leaves, in proportions that vary by season.
For a large lemur, the diademed sifaka is rather athletic, being capable of lateral aerial propulsion of up to 30 kilometers per hour, a result of muscular leg thrusting action pushing off from a vertical tree trunk. It is possible, although not proven, that its vigorous health characteristics are enhanced from high consumption of two plants which contain high concentrations of alkaloids. This species is arboreal, and only rarely are seen on the ground; moreover, it is a vertical clinger and lateral leaper.
The diademed sifaka makes a warning call resembling the sound "kiss-sneeze" when a terrestrial predator is perceived; the sole terrestrial predators of P. diadema are the Fossa and Nile crocodile.
Sexual maturity occurs after age two or three, with the male maturing somewhat more slowly than the female. Little is known of mating behaviour; however, it is believed that the female is receptive to mating only a few days per year. Being dominant, the female has the greatest input to mate selection. Copulation occurs in the summer (around December), and the expected number of births is one offspring per female per annum.
The diademed sifaka is classified as Critically Endangered on the IUCN Red List. As of the year 2002, population estimates for the species range between 6,000 and 10,000 individuals. The primary threat is habitat reduction due to shifting cultivation by native peoples. This threat is also present even within designated national parks, which are sufficiently distant from the center of government, that enforcement of existing national laws protecting P. diadema habitat is problematic. Pressures of overpopulation in central and eastern Madagascar are causing many of the rural poor to seek subsistence by seizing whatever forest lands are available and undertaking slash-and-burn tactics as their initial step in a shifting cultivation system. Returns from such land use are usually meager, yielding small amounts of charcoal, firewood or grass crop for grazing of zebu.
The diademed sifaka and four other sifaka species form a tight species group within the Propithecus genus. The other four species are Milne-Edwards' sifaka (Propithecus edwardsi), Perrier's sifaka (P. perrieri), the golden-crowned sifaka, (P. tattersalli), and the silky sifaka (P. candidus). All of these species have luxuriant silky coats and are powerful leapers. They share similar characteristics of gestation length (four months), age of sexual maturity, female dominance, life expectancy (18 years) and propensity for sunbathing while stretched out on a branch. They differ distinctly in colouration and markings, except for having universally totally black faces.
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