Diademed sifaka

This sheet covers all eastern sifakas, or the P. diadema group, including P. candidus, P. diadema, P. edwardsi, P. perrieri and P. tattersalli

SOCIAL ORGANIZATION AND BEHAVIOR

Long-term research on and information about social organization and behavioral patterns in the diademed group of sifakas is limited to studies conducted on Milne-Edwards’ sifakas (P. edwardsi) at Ranomafana National Park. Milne-Edwards’ sifakas have average group size of 4.8 but can have between three and nine individuals (Wright 1995; 1998). The social structure of these groups varies based on size and can be polygynandrous, polyandrous, polygynous, or monogamous. Because group size is so small, variations in composition, such as an increase in the number of adult females or adult males, necessitate a shift in the type of social organization or mating system (Pochron & Wright 2003; Pochron et al. 2004). This flexibility may be related to environmental factors such as increased feeding competition for seasonal resources and the presence of predators. One explanation for group living in primates is increased vigilance and detection of predators; it is safer for animals to travel in groups than as single individuals. Where there are predators and highly seasonal resources, though, group size may be limited because of increased feeding competition between group members. Sifakas may balance the need for predator protection with minimal feeding competition by keeping group size small and shifting the organization throughout the year to enhance mating opportunities (Pochron & Wright 2003; Pochron et al. 2004).

Brief field studies and rapid censuses provide some information about the social structure and group composition of silky sifaka (P. candidus) groups. At Marojejy National Park and Anjanaharibe-Sud Special Reserve, silky sifakas live in multi-male/multi-female groups and in male-female pairs of 2 to 9 individuals. Average group size is 4 (Schmid & Smolker 1998; Sterling & McFadden 2000; Patel 2006a). Adult male immigration and emigration have been observed one time each since 2001 within the one long-term study group at Marojejy. No adult females have yet been seen to change groups (ER Patel, pers. comm.). Similarly, the little-studied Perrier’s sifaka (P. perrieri) lives in small groups ranging in size from one to six individuals and includes adult males and females as well as their offspring (Mayor & Lehman 1999). Propithecus tattersalli lives in small groups ranging in size from three to six individuals, but average group size is five individuals (Vargas et al. 2002). While these species have not been studied as extensively as other members of the genus Propithecus, estimates of group size are similar for better studied species such as P. edwardsi and P. diadema (Meyers & Ratsirarson 1989). Diademed sifakas (P. diadema) live in female dominated, multi-male/multi-female groups of up to eight individuals of all ages (Powzyk 1997; Powzyk 2001). About half of P. edwardsi individuals of both sexes migrate from their natal group with females leaving before maturity and males both before and after maturity (Wright 1995; Pochron et al. 2004). Given the similarities in ecological patterns and group size among sifakas of the diadema group, future research may reveal similar patterns of social behavior such as group transfer and dominance patterns.

Daily, the silky sifaka (P. candidus) spends 44.4% of its time resting, 21.9% foraging, 16.8% engaged in social behavior, and spends the rest of the day sleeping, moving or engaging in other activities (Patel 2006a). P. diadema spends its time somewhat differently, with 37.8% of its time spent feeding, 49.4% resting, 2.4% in social behavior, 5.1% moving, and the rest in other activities (Powzyk 1997).

REPRODUCTION

Most reproductive data for the eastern sifakas are limited to the Milne-Edwards’ sifaka (P. edwardsi) and the golden-crowned sifaka (P. tattersalli). Sifakas have numerous types of mating system, often at once and in the same population. P. edwardsi populations can have polygynous, polygynandrous, polyandrous, and monogamous mating systems at once during mating season in surprisingly even proportions relative to one another (Pochron & Wright 2003). As in other Malagasy lemurs, sifakas reproduce seasonally. Milne-Edwards’ and golden-crowned sifakas (P. tattersalli) mate during the austral summer, in December and January. As would be expected following seasonal mating, they also show a strong seasonality of births, usually giving birth during the winter between May and July, with the majority of births in June (Meyers & Wright 1993; Hemingway 1999; Pochron et al. 2004). P. tattersalli normally mates almost two months earlier than P. edwardsi during the summer (Meyers & Wright 1993). Copulations only occur over a 24-hour period when the female is in estrous and fertile. However, females within a group are fertile on different days (Wright 1995; Pochron & Wright 2003). Fertility is signaled by an approximately 10-hour long, externally visible pink genital swelling in females (Pochron & Wright 2003). As the breeding season nears, males also exhibit a testicular volume increase over any other time of the year (Pochron et al. 2002).

Copulation is short in duration, often between only 30 and 90 seconds and consists of a single mount (Wright 1995; Pochron & Wright 2002).

Gestation for P. edwardsi averages 179 days (6 months) and gestation for P. tattersalli is just under six months (Meyers & Wright 1993; Wright 1995). Age at first birth for P. edwardsi females is around 4 years of age with an increase in fertility at 6 (Meyers & Wright 1993; Wright 1995; Pochron et al. 2004). Males reach reproductive maturity at 5 years old (Wright 1995). Interbirth interval for P. edwardsi averages 1.56 years, but due to strict reproductive seasonality, the interval is one year around half of the time and two years the rest of the time resulting in the intermediate average (Pochron et al. 2004). Similarly, the interbirth interval of P. candidus averages 1.67 years (Patel 2006a). The true value of the inter-birth interval is affected by whether or not the infant survives its first year (Pochron et al. 2004). In the same vein, infanticide is recorded in P. edwardsi, possibly as a male strategy to shorten the inter-birth interval from the two years typical of mothers with surviving infants to one year (Wright 1995; Erhart & Overdorff 1998).

PARENTAL CARE

Information about infant development and parental care in the eastern sifakas is scarce and comes almost exclusively from the Milne-Edwards’ sifaka (P. edwardsi) in the wild. At birth, the species averages 156 g (5.5 oz) (Glander et al. 1992). Births are synchronous within the group, with 6 of 8 births in one study occurring during a one week window (Pochron & Wright 2003). The infant spends more time on its mother than on other group members and the mother is the main care provider (Grieser 1992). Although mothers are the primary caregivers in other sifakas as well, Propithecus non-mothers are known to engage in substantial infant care on occasion that can include allonursing and carrying. Amongst sifakas, allonursing has only been observed in P. edwardsi and P. candidus. Less extreme forms of allocare such as grooming and playing are often seen in both eastern and western sifakas (Jolly 1966; Grieser 1992; Patel et al. 2003a; reviewed in Patel 2007b).

From birth in P. edwardsi, the infant is carried ventrally, only moving to a dorsal riding position starting in the third week of life and is increasingly seen in that position thereafter. Also around this time, the infant starts to feed and is seen alone and not in physical contact with any other individuals for the first time. Allogrooming and self-grooming commence in the fourth week of life. Play starts by week 6 of life but rarely occurs between the infant and the mother and most often occurs between the infant and a juvenile. Either way, play with other group sifakas is uncommon (Grieser 1992). By one year old, juveniles weigh 2500 g (88.2 oz) (Glander et al. 1992). Infant mortality is high in P. edwardsi, with over half of female infants dying in their first year of life and only a quarter making it to reproductive age at four years old (Pochron et al. 2004). At night, mothers will still sleep with their offspring until the young are two years old (Wright 1995). P. tattersalli mothers will wean their infants 5 months after birth and P. edwardsi will wean their offspring 6 months after birth both of which correspond to just slightly before the subsequent breeding season (Meyers & Wright 1993).

COMMUNICATION

Adult eastern sifakas have a moderately sized vocal repertoire of about 7 call types (Patel et al. 2005b). Infants have several specialized vocalizations as well. Despite the relatively small size of their vocal repertoire, some eastern sifakas are highly vocal with high call rates averaging 7 calls per hour per individual in silky sifakas (ER Patel pers. comm.). The most frequently emitted vocalizations are low amplitude, low frequency, tonal “hum” and “mum” vocalizations. These contact calls are used in a variety of circumstances including group movement, affiliation, foraging, and while resting. The loudest vocalizations produced are their alarm calls which are often emitted in a contagious or antiphonal fashion by all group members. Broad-band noisy “aerial disturbance roars” are emitted with open mouths to overhead raptors and other aerial disturbances such as falling trees and small birds. Sometimes they stare skyward and drop vertically in the trees while producing these loud aerial roars (Wright 1998; Patel et al. 2003b). Eastern sifakas also emit a general disturbance alarm call, the sneeze-like “Zzuss!” vocalization, that is produced with closed mouths in response to lost calls or “howls” by other group members, terrestrial disturbances, terrestrial predators, and other high arousal contexts (Wright 1998; Patel et al. 2003b). Acoustic analyses have revealed sex and individual differences in the acoustic structure of “Zzuss” vocalizations (Patel et al. 2005c; 2006). In all sifakas, greater context specificity is apparent for aerial disturbance alarm calls than terrestrial disturbance alarm calls (Fichtel & Kappeler 2002; Patel et al. 2003b); a pattern also seen in anthropoid alarm call systems such as vervet monkeys (Chlorocebus sp.) and capuchin monkeys (Cebus sp.) (Seyfarth et al. 1980; Digweed et al. 2005).

LISTEN TO VOCALIZATIONS

• Propithecus candidus: Chatter-squeal during agonism  (Erik Patel; Cornell University)
• Propithecus candidus: Howls  (Erik Patel; Cornell University)
• Propithecus candidus: Multiple animal aerial roars  (Erik Patel; Cornell University)
• Propithecus candidus: Single animal roars  (Erik Patel; Cornell University)
• Propithecus candidus: Zzuss call  (Erik Patel; Cornell University)
• Propithecus diadema: Chatter, Squeal and Purr  (Erik Patel, John Anderson, Mitchell T. Irwin; Cornell and Stony Brook University)
• Propithecus diadema: Howl  (Erik Patel, John Anderson, Mitchell T. Irwin; Cornell and Stony Brook University)
• Propithecus diadema: Hum  (Erik Patel, John Anderson, Mitchell T. Irwin; Cornell and Stony Brook University)
• Propithecus diadema: MMM  (Erik Patel, John Anderson, Mitchell T. Irwin; Cornell and Stony Brook University)
• Propithecus diadema: Purr  (Erik Patel, John Anderson, Mitchell T. Irwin; Cornell and Stony Brook University)
• Propithecus diadema: Roar  (Erik Patel, John Anderson, Mitchell T. Irwin; Cornell and Stony Brook University)
• Propithecus diadema: Zzuss  (Erik Patel, John Anderson, Mitchell T. Irwin; Cornell and Stony Brook University)
• Propithecus edwardsi: Aerial roars  (Erik Patel; Cornell University)
• Propithecus edwardsi: Mmm call  (Erik Patel; Cornell University)

As in other prosimians, olfactory communication is well developed in sifakas. Eastern sifakas possess several specialized scent-marking glands that include a sebaceous chest gland only found in males and mixed apocrine-sebaceous ano-genital glands in both sexes (Schilling 1979). Sifakas do not allomark, as in Eulemur, by directly scent-marking conspecifics. Females scent-mark trees by rubbing their anogenital glands against trees in a rhythmic vertical motion. Males scent-mark trees in several ways, by rubbing them with their chest gland, ano-genital glands, or a combination of the two (Pochron et al. 2005b). Males routinely gouge trees with their toothcombs just prior to chest marking which leaves long lasting visible marks. Eastern sifakas do not eat bark or gum, so such non-nutritive male tree gouging is likely communicative in function (ER Patel pers. comm.). Both sexes often urinate while scent-marking. In P. edwardsi, dominant individuals of both sexes mark more than subordinate individuals. Female scent-marking rates are not highest during the mating season, but peak just before during the lactation/dispersal season. Similarly, male rates also peak during the dispersal season (Pochron et al. 2005a; 2005b). The chemical composition of P. edwardsi ano-genital gland secretions differs between the birth and mating seasons, and could be due to seasonal differences in diet or hormone levels (Hayes et al. 2006). Males scent-mark twice as often as females (Pochron et al. 2005b). However, female scent-marks are responded to far more often and more quickly than male marks. In P. candidus, for example, only 17% of male marks are responded to by other group members but 71% of female marks received a response on average within 61 seconds (Patel 2006b). In both P. edwardsi and P. candidus, male overmarking of a female’s mark is the most common response, followed by males overmarking the scent-marks of other males. Male eastern sifakas preferentially use one type of scent-marking, combined chest-ano-genital marking, when depositing an overmark (Andrianandrasana et al. 2007). The high rates of overmarking practiced by male eastern sifakas lead to totem-tree marking in which certain trees are covered with male gouge marks which probably reflects competition for females. Totem-trees may occur along territorial borders, but are generally observed throughout the home range in P. candidus and P. edwardsi (Powzyk 1997; Ritchie & Patel 2006; ER Patel pers. comm.).

Content last modified: February 4, 2008

Written by Kurt Gron. Reviewed by Erik Patel.

Cite this page as:
Gron KJ. 2008 February 4. Primate Factsheets: Diademed sifaka (Propithecus diadema) Behavior . <http://pin.primate.wisc.edu/factsheets/entry/diademed_sifaka/behav>. Accessed 2020 July 30.

This sheet covers all eastern sifakas, or the P. diadema group, including P. candidus, P. diadema, P. edwardsi, P. perrieri and P. tattersalli

INTERNATIONAL STATUS

For individual primate species conservation status, please search the IUCN Red List.
Also search the current scientific literature for primate conservation status (overall as well as for individual species), and visit CITES (Convention on International Trade in Endangered Species of Wild Fauna and Flora).

Conservation information last updated in 2008 follows, for comparison:

IUCN Red List: P. candidus, P. perrieri: CR; P. diadema, P. edwardsi, P. tattersalli: EN (What is Red List?)
Key: CR = Critically endangered, CR = Critically endangered, EN = Endangered, EN = Endangered, EN = Endangered

Between 2004 and 2006, the IUCN/SSC Primate Specialist Group included both P. candidus and P. perrieri on their list of the world’s 25 most endangered primates (Mittermeier et al. 2006b).

CONSERVATION THREATS

Threat: Human-Induced Habitat Loss and Degradation

As is the case with most Malagasy primate species, habitat loss and hunting pose the greatest threats to the P. diadema group. It is important to note however, that there can be extreme variation in threats to the eastern sifakas by region, such that a threat that is non-existent in one region may be quite severe in another (Irwin 2006b).

Sifaka habitat can be lost or degraded in a number of ways including clearing for swidden agriculture, gold mining, uncontrolled grass fires, pasture for livestock, and tree cutting for construction materials, charcoal and firewood (Mayor & Lehman 1999; Vargas et al. 2002; Mittermeier et al. 2006a; Schwitzer et al. 2006). Slash-and-burn agriculture is more productive when the forest being cleared is primary forest and the resulting fields are only productive for several years, after which new forest must be cleared. The result is a very destructive domino effect of deforestation (Vargas et al. 2002). In addition, yearly brushfires are set to maintain deforested areas, significantly impeding forest re-growth (Meyers & Ratsirarson 1989). While some species of sifaka, such as P. diadema are able to survive in fragmented forest, social group cohesion suffers (Irwin 2007).

The illegal local production of rum also presents a unique threat to sifaka populations. This manufacturing process threatens sifakas in three ways. First, the growing of sugarcane on fields cleared from forest for rum production contributes to habitat destruction. Second, rum distillation requires large amounts of firewood is cut from forests. Finally, the use of tree bark from sifaka food trees in the manufacturing process destroys species that are ecologically important to sifakas. Increasing production of rum for a commercial market will only further threaten the forest ecosystems of the sifaka (Irwin 2004).

Rahiaka trees (Chrysophyllum bonivianum), important food trees for sifakas, are often utilized as sources of latex. Unfortunately, while it is possible to tap the latex without felling the tree, they are often cut down because it is easier and more expedient to access the latex in such fashion. Other trees important to sifakas are also cut selectively for other purposes, such as for making bee boxes (Irwin et al. 2000).

Illegal logging of precious wood, such as rosewood and ebony, has emerged as one of the most severe threats to Madagascar’s northeastern rainforests. Thousands of logs, worth millions of dollars, have recently been confiscated at ports of Vohémar, Antalaha, and Toamasina. Most of these logs were harvested from the two largest protected areas in the region, Masoala National Park and Marojejy National Park. Harvesting these extremely heavy hardwoods is a labor intensive activity requiring coordination between local residents who manually cut the trees, but receive little profit, and a criminal network of exporters, domestic transporters, and corrupt officials who initiate the process and reap most of the profits. The impacts of such selective logging include violating local taboos as well as ecological consequences such as increased likelihood of fire, invasive species, impaired habitat, and loss in genetic diversity (Patel 2007a).

Threat: Harvesting (hunting/gathering)

In some regions of its range, the consumption of sifakas is “fady” (taboo) (Meyers & Ratsirarson 1989; Meyers 1993a; Mayor & Lehman 1999). This serves to at least partially prevent hunting of the species as it reduces the demand for their meat. However, even if consumption is fady, hunting of them is not necessarily so. In addition, outsiders not native to areas where sifaka consumption is fady often do not observe such taboos. As a result, because of the immigration of outsiders from other regions into those with fady against sifaka consumption, hunting is increasing in areas where it formerly was not a threat (Meyers & Ratsirarson 1989). In addition, there is no fady against the hunting or eating of P. candidus in its range (Mittermeier et al. 2006a). Hunting of sifakas by gold miners who have immigrated to areas of fady has been reported, and lemurs are sometimes eaten daily by some groups of miners (Meyers 1996; Mittermeier et al. 2006a). Lemur hunting is undertaken in several ways, using blowguns, firearms, slingshots, snares, and box traps (Mayor & Lehman 1999; Irwin et al. 2000; Wright pers. comm. cited in Mittermeier et al. 2006a). There is variability in regional consumption in sifakas, and in some regions, such as near Betampona, they are a favored food (Welch & Katz 1992).

Per hunt, the lemur take ranges quite a bit, from only a couple of lemurs killed up to as many as around 70 individuals. Dead lemurs are often sold for around $4. Middle-class Malagasy in some regions consider lemur a delicacy and may hire and equip poverty-stricken hunters to procure the food for them even though plenty of other meats are available (Patel et al. 2005).

Threat: Pollution

There is evidence that climate change may be affecting sifakas by reducing rainfall and subsequently reducing the availability of food leaves which older mothers with degraded teeth are able to chew. Because female sifakas rely on leaves as food to produce milk for offspring, any reduction in rainfall affects their ability to produce milk, reducing the chances of survival of their offspring (Gross 2006).

Threat: Intrinsic Factors

Eastern sifakas are susceptible to a number of naturally occurring threats to their health. These include parasitic tapeworms (Cesetodes) in addition to a number of potentially infectious bacteria including E. coli, Enterobacter, and Streptococcus (Junge & Sauther 2006). Also, in one study population of P. tattersalli, 60% of individuals had a larval parasite which has the potential to be detrimental to their health (Meyers 1993a).

LINKS TO MORE ABOUT CONSERVATION

CONSERVATION INFORMATION

• Angels of the Forest  (full length program; Vimeo: Sharon Pieczenik; 2009; Flash)
• The Lemurs of Marojejy and Anjaraharibe-Sud  (2005; PDF)
• Trouble in Lemur Land  (full length program; Vimeo: Erik Patel and Earth-Touch; 2011; Flash)
• Links for all species

CONSERVATION NEWS

• Silky sifakas fight for survival in Madagascar  (BBC; March 15, 2012)
• Plight of the Lemur: A Movie  (New York Times; September 7, 2011)
• Already on the edge, lemurs could become victims of climate change  (Mongabay; June 8, 2010)
• Lemur Forests Pillaged by “Gangs” as Madagascar Reels  (National Geographic News; March 24, 2009)
• Researcher hears a cry for help from rare silky sifakas  (Seattle Times; January 20, 2006)
• Links for all species

ORGANIZATIONS INVOLVED IN Propithecus diadema CONSERVATION

• LVDI International

Content last modified: February 4, 2008

Written by Kurt Gron. Reviewed by Erik Patel.

Cite this page as:
Gron KJ. 2008 February 4. Primate Factsheets: Diademed sifaka (Propithecus diadema) Conservation . <http://pin.primate.wisc.edu/factsheets/entry/diademed_sifaka/cons>. Accessed 2020 July 30.

This sheet covers all eastern sifakas, or the P. diadema group, including P. candidus, P. diadema, P. edwardsi, P. perrieri and P. tattersalli

The following references were used in the writing of this factsheet. To find current references for Propithecus, search PrimateLit.

REFERENCES

Andrianandrasana LH, Patel ER, Wright PC. 2007. A comparison of scent overmarking in two species of wild rainforest sifakas: silky sifakas (Propithecus candidus) and Milne-Edwards’ sifakas (Propithecus edwardsi). Prosimian Congress 2007 Abstracts: 54-5.

Banks MA, Ellis ER, Antonio, Wright PC. 2007. Global population size of a critically endangered lemur, Perrier’s sifaka. Anim Conserv 10(2):254-62.

Demes B, Jungers WL, Fleagle JG, Wunderlich RE, Richmond BG, Lemelin P. 1996. Body size and leaping kinematics in Malagasy vertical clingers and leapers. J Hum Evol 31(4): 367-88.

Digweed SM, Fedigan LM, Rendall D. 2005. Variable specificity in the anti-predator vocalizations and behaviour of the white-faced capuchin, Cebus capucinus. Behaviour 142(8):997-1021.

Erhart EM, Overdorff DJ. 1998. Infanticide in Propithecus diadema edwardsi: an evaluation of the sexual selection hypothesis. Intl J Primatol 19(1):73-81.

Fichtel C, Kappeler PM. 2002. Anti-predator behavior of group-living Malagasy primates: mixed evidence for a referential alarm call system. Behav Ecol Sociobiol 51(3):262-75.

Garbutt N. 1999. Mammals of Madagascar. Sussex (UK): Pica Pr. 320 p.

Glander KE, Wright PC, Daniels PS, Merenlender AM. 1992. Morphometrics and testicle size of rain forest lemur species from southeastern Madagascar. J Hum Evol 22(1):1-17.

Grieser B. 1992. Infant development and parental care in two species of sifakas. Primates 33(3):305-14.

Gross M. 2006. Leaves clue to lemur peril. Curr Biol 16(21):R900.

Groves C. 2001. Primate taxonomy. Washington DC: Smithsonian Inst Pr. 350 p.

Hayes RA. Morelli TL, Wright PC. 2006. Volatile components of lemur scent secretions vary throughout the year. Am J Primatol 68(12):1202-7.

Hemingway CA. 1996. Morphology and phenology of seeds and whole fruit eaten by Milne-Edwards’ sifaka, Propithecus diadema edwardsi, in Ranomafana National Park, Madagascar. Int J Primatol 17(5): 637-59.

Hemingway CA. 1998. Selectivity and variability in the diet of Milne-Edwards’ sifakas (Propithecus diadema edwardsi): implications for folivory and seed-eating. Int J Primatol 19(2): 355-77.

Hemingway CA. 1999. Time budgets and foraging in a Malagasy primate: do sex differences reflect reproductive condition and female dominance? Behav Ecol Sociobiol 45:311-22.

Irwin MT, Smith TM, Wright PC. 2000. Census of three eastern rainforest sites north of Ranomafana national park: preliminary results and implications for lemur conservation. Lemur News 5:20-2.

Irwin MT, Raharison FJ-L, Rakotoarimanana H, Razanadrakoto E, Ranaivoson E, Rakotofanala J, Randrianarimanana C. 2007. Diademed sifakas (Propithecus diadema) use olfaction to forage for the inflorescences of subterranean parasitic plants (Balanophoraceae: Langsdorffia sp., and Cytinaceae: Cytinus sp.). Am J Primatol 69(4):471-6.

Irwin MT. 2006a. Ecological impacts of forest fragmentation on diademed sifakas (Propithecus diadema) at Tsinjoarivo, eastern Madagascar: implications for conservation in fragmented landscapes. PhD dissertation, Stony Brook University, Stony Brook, NY.

Irwin MT. 2006b. Ecologically enigmatic lemurs: the sifakas of the eastern forests (Propithecus candidus, P. diadema, P. edwardsi, P. perrieri, and P. tattersalli). In: Gould L, Sauther ML, editors. Lemurs: ecology and adaptation. New York: Springer Pr. p 305-26.

Irwin MT. 2004. Illegal rum production threatens health of lemur populations at Tsinjoarivo, eastern central Madagascar: brief report and request for information. Lemur News 9:16-7.

Irwin MT. 2007. Living in forest fragments reduces group cohesion in diademed sifakas (Propithecus diadema) in eastern Madagascar by reducing food patch size. Am J Primatol 69(4):434-47.

Irwin MT, Johnson SE, Wright PC. 2005. The state of lemur conservation in south-eastern Madagascar: population and habitat assessments for diurnal and cathemeral lemurs using surveys, satellite imagery and GIS. Oryx 39(2):204-18.

Jolly A. 1966. Lemur behavior: a Madagascar field study. Chicago:U Chicago Pr.

Junge RE, Sauther ML. 2006. Overview on the health and disease ecology of wild lemurs: conservation implications. In: Gould L, Sauther ML, editors. Lemurs: ecology and adaptation. New York: Springer Pr. p 423-40.

Kappeler PM. 1990. The evolution of sexual size dimorphism in prosimian primates. Am J Primatol 21(3): 201-14.

Kelley E, Mayor MI. 2002. Preliminary study of the silky sifaka (Propithecus diadema candidus) in northeast Madagascar. Lemur News 7: 16-8.

Lehman SM, Mayor M. 2004. Dietary patterns in Perrier’s sifakas (Propithecus diadema perrieri): a preliminary study. Am J Primatol 62(2): 115-22.

Lehman SM, Mayor M, Wright PC. 2005. Ecogeographic size variations in sifakas: a test of the resource seasonality and resource quality hypotheses. Am J Phys Anthro 126(3): 318-28.

Mayor MI, Lehman SM. 1999. Conservation of Perrier’s sifaka (Propithecus diadema perrieri) in Analamera Special Reserve, Madagascar. Lemur News 4:21-3.

Mayor MI, Sommer JA, Houck ML, Zaonarivelo JR, Wright PC, Ingram C, Engel SR, Louis Jr. EE. 2004. Specific status of Propithecus spp. Int J Primatol 25(4): 875-900.

Meyers DM. 1993a. Conservation status of the golden-crowned sifaka, Propithecus tattersalli. Lemur News 1(1):6-8.

Meyers DM. 1993b. The effects of resource seasonality on behavior and reproduction in the golden-crowned sifaka (Propithecus tattersalli, Simons, 1988) in three Malagasy forests. PhD dissertation, Duke Univeristy, Durham, N.C. 231 p.

Meyers DM, Ratsirarson J. 1989. Distribution and conservation of two endangered sifakas in northern Madagascar. Prim Cons 10: 81-6.

Meyers DM, Wright PC. 1993. Resource tracking: food availability and Propithecus seasonal reproduction. In: Kappeler PM, Ganzhorn JU, editors. Lemur social systems and their ecological basis. New York: Plenum Pr. p 179-92.

Meyers DM. 1996. Update on the endangered sifaka of the north. Lemur News 2:13-4.

Mittermeier RA, Konstant WR, Nicoll ME, Langrand O. 1992. Lemurs of Madagascar: an action plan for their conservation 1993-1999. Gland (CH):IUCN. 58 p.

Mittermeier RA, Konstant WR, Hawkins F, Louis EE, Langrand O, Ratsimbazafy J, Rasoloarison R, Ganzhorn JU, Rajaobelina S, Tattersall I. 2006a. Lemurs of Madagascar, second edition. Washington DC: Cons Int. 520 p.

Mittermeier RA, Valladares-Pádua, Rylands AB, Eudey AA, Butynski TM, Ganzhorn JU, Kormos R, Aguiar JM, Walker S. 2006b. Primates in peril: the world’s 25 most endangered primates, 2004-2006. Prim Conserv 20:1-28.

Patel ER. 2006a. Activity budget, ranging, and group size in silky sifakas (Propithecus candidus). Lemur News 11:42-5.

Patel ER, Coke CS, Ritchie A, Santorelli C. 2003a. Alloparental care (including allonursing) in free-ranging silky sifakas (Propithecus diadema candidus) in a primary northeastern montane rainforest in Madagascar [abstract]. Am J Primatol 60(Suppl 1):71.

Patel ER, Coke CS, Ritchie A, Santorelli C. 2003b. Assessing production specificity of free ranging silky sifaka (Propithecus diadema candidus) “antipredator” vocalizations: weak evidence for “aerial predator” but not “terrestrial predator” calls. Am J Primatol 60(Suppl 1):71-2.

Patel ER, Anderson JD, Owren MJ. 2006. Exploring the function of “Zzuss” alarm vocalizations in wild silky sifakas (Propithecus candidus): moderate evidence for individual distinctiveness [abstract]. Intl J Primatol 27(suppl 1):504.

Patel ER. 2007a. Logging of rare rosewood and palisandre (Dalbergia spp.) within Marojejy National Park, Madagascar. Madag Conserv Develop 2:11-6.

Patel ER. 2007b. Non-maternal infant care in wild silky sifakas (Propithecus candidus). Lemur News 12:39-42.

Patel ER, Anderson JD, Irwin MT, Owren MJ. 2005b. Quantifying the vocal repertoire of wild adult diademed sifakas (Propithecus diadema diadema) in Madagascar. Am J PRimatol 66(suppl 1):48.

Patel ER. 2006b. Scent-marking in wild silky sifakas (Propithecus candidus) in Madagascar: sex differences and seasonal effects in usage and response across multiple scent-mark types [abstract]. Intl J Primatol 27(suppl 1):496.

Patel ER, Anderson JD, Owren MJ. 2005c. Sex differences in the acoustic structure of an alarm vocalization in a monoporphic primate: wild silky sifakas (Propithecus candidus) of northeastern Madagascar. Am J Primatol 66(suppl 1):46-7.

Patel ER, Meyers D, Hawkins F. 2007. Silky sifaka, Propithecus candidus, 1871. In: Mittermeier RA, Ratsimbazafy J, Rylands AB, Williamson L, Oates JF, Mbora D, Ganzhorn JU, Rodríguez-Luna E, Palacios E, Heymann EW, Kierulff MCM, Yongcheng L, Supriatna J, Roos C, Walker S, Aguiar JM. Primates in peril: the world’s 25 most endangered primates, 2006-2008. Prim Conserv 22:1-40.

Patel ER, Marshall JJ, Parathian H. 2005. Silky sifaka (Propithecus candidus) conservation education in northeastern Madagascar. Lab Prim News 44(3):8-11.

Patel ER. 2005. Silky sifaka predation (Propithecus candidus) by a fossa (Cryptoprocta ferox). Lemur News 10: 25-7.

Pochron ST, Tucker WT, Wright PC. 2004. Demography, life history, and social structure in Propithecus diadema edwardsi from 1986-2000 in Ranomafana National Park, Madagascar. Am J Phys Anthro 125(1): 61-72.

Pochron ST, Wright PC. 2002. Dynamics of testes size compensates for variation in male body size. Evol Ecol Res 4(4):577-85.

Pochron ST, Wright PC, Schaentzler E, Ippolito M, Rakotonirina G, Ratsimbazafy R, Rakotosoa R. 2002. Effect of season and age on the gonadosomatic index of Milne-Edwards’ sifakas (Propithecus diadema edwardsi) in Ranomafana national park, Madagascar. Intl J Primatol 23(2):355-64.

Pochron ST, Morelli TL, Terranova P, Scirbona J, Cohen J, Kunapareddy G, Rakotonirina G, Ratsimbazafy R, Rakotosoa R, Wright PC. 2005a. Patterns of male scent-marking in Propithecus edwardsi of Ranomafana national park, Madagascar. Am J Primatol 65(2):103-15.

Pochron ST, Morelli TL, Scribona J, Wright PC. 2005b. Sex differences in scent marking in Propithecus edwardsi of Ranomafana national park, Madagascar. Am J Primatol 66(2):97-110.

Pochron ST, Wright PC. 2003. Variability in adult group compositions of a prosimian primate. Behav Ecol Sociobiol 54(3): 285-93.

Powzyk JA, Mowry CB. 2003. Dietary and feeding differences between sympatric Propithecus diadema diadema and Indri indri. Int J Primatol 24(6): 1143-62.

Powzyk JA. 2001. Social organisation and food partitioning in two large bodied indrids: Propithecus diadema diadema and Indri indri [abstract]. The XVIIIth congress of the International Primatological Society. Primates in the new millennium. Adelaide (Australia): Int Primatol Soc. p 322.

Powzyk JA. 1997. The socio-ecology of two sympatric indriids: Propithecus diadema diadema and Indri indri, a comparison of feeding strategies and their possible repercussions on species-specific behavior. PhD dissertation, Duke University, Durham, NC. 307 p.

Richard AF. 2003. Propithecus: sifakas. In: Goodman SM, Benstead JP, editors. The natural history of Madagascar. Chicago: U Chicago Pr. p 1344-8.

Ritchie A, Patel ER. 2006. The existence and potential function of “totem-tree” scent-marking in silky sifakas (Propithecus candidus). Intl J Primatol 27(Suppl 1):Abstract #359.

Rowe N. 1996. The pictorial guide to the living primates. East Hampton (NY): Pogonias Pr. 263 p.

Schilling A. 1979. Olfactory communication in prosimians. In: Doyle GA, Martin RA. The study of prosimian behavior. New York: Academic Pr. p 461-542.

Schmid J, Smolker R. 1998. Lemurs of the reserve special d’Anjanaharibe-Sud, Madagascar. Fieldiana: Zoology 90:227-40.

Schwitzer C, Arnould O, Rakotosamimanana B. 2006. An international conservation and research programme for Perrier’s sifaka (Propithecus perrieri Lavauden, 1931) in northern Madagascar. Lemur News 11:12-21.

Seyfarth RM, Cheney DL, Marler P. 1980. Vervet monkey alarm calls: semantic communication in a free-ranging primate. Anim Behav 28:1070-94.

Sterling E, McFadden K. 2000. Rapid census of lemur populations in the Parc National de Marojejy, Madagascar. Field Zool 97: 265-74.

Tattersall I. 1982. The primates of Madagascar. New York: Columbia Univ Pr. 382 p.

Tattersall I. 1986. Notes on the distribution and taxonomic status of some subspecies of Propithecus in Madagascar. Folia Primatol 46(1): 51-63.

Vargas A, Jiménez I, Palomares F, Palacios MJ. 2002. Distribution, status, and conservation needs of the golden-crowned sifaka (Propithecus tattersalli). Biol Conserv 108(3): 325-34.

Welch C, Katz A. 1992. Survey and census work on lemurs in the natural reserve of Betampona in eastern Madagascar with a view to restocking. Dodo, J Wild Preserv Trusts 28:45-58.

Wright PC. 1995. Demography and life history of free-ranging Propithecus diadema edwardsi in Ranomafana national park, Madagascar. Intl J Primatol 16(5):835-54.

Wright PC. 1987. Diet and ranging patterns of Propithecus diadema edwardsi in Madagascar [abstract]. Am J Phys Anth 72:271

Wright PC. 1998. Impact of predation risk on the behaviour of Propithecus diadema edwardsi in the rain forest of Madagascar. Behaviour 135(4): 483-512.

Wright PC. 1992. Primate ecology, rainforest conservation, and economic development: building a national park in Madagascar. Evol Anth 1(1):25-33.

Wright PC, Heckscher SK, Dunham AE. 1997. Predation on Milne-Edward’s sifaka (Propithecus diadema edwardsi) by the fossa (Cryptoprocta ferox) in the rain forest of southeastern Madagascar. Folia Primatol 68(1): 34-43.

Content last modified: February 4, 2008

This sheet covers all eastern sifakas, or the P. diadema group, including P. candidus, P. diadema, P. edwardsi, P. perrieri and P. tattersalli

AUDIO

• Propithecus candidus: Chatter-squeal during agonism  (Erik Patel; Cornell University)
• Propithecus candidus: Howls  (Erik Patel; Cornell University)
• Propithecus candidus: Multiple animal aerial roars  (Erik Patel; Cornell University)
• Propithecus candidus: Single animal roars  (Erik Patel; Cornell University)
• Propithecus candidus: Zzuss call  (Erik Patel; Cornell University)
• Propithecus diadema: Chatter, Squeal and Purr  (Erik Patel, John Anderson, Mitchell T. Irwin; Cornell and Stony Brook University)
• Propithecus diadema: Howl  (Erik Patel, John Anderson, Mitchell T. Irwin; Cornell and Stony Brook University)
• Propithecus diadema: Hum  (Erik Patel, John Anderson, Mitchell T. Irwin; Cornell and Stony Brook University)
• Propithecus diadema: MMM  (Erik Patel, John Anderson, Mitchell T. Irwin; Cornell and Stony Brook University)
• Propithecus diadema: Purr  (Erik Patel, John Anderson, Mitchell T. Irwin; Cornell and Stony Brook University)
• Propithecus diadema: Roar  (Erik Patel, John Anderson, Mitchell T. Irwin; Cornell and Stony Brook University)
• Propithecus diadema: Zzuss  (Erik Patel, John Anderson, Mitchell T. Irwin; Cornell and Stony Brook University)
• Propithecus edwardsi: Aerial roars  (Erik Patel; Cornell University)
• Propithecus edwardsi: Mmm call  (Erik Patel; Cornell University)

VIDEO & WEBCAMS

• Acrobatic Feeding  (0:38; Erik Patel, Cornell University; Mpeg)
• Angels of the Forest  (full length program; Vimeo: Sharon Pieczenik; 2009; Flash)
• Grooming of nose by two males  (1:10; Erik Patel, Cornell University; Mpeg)
• Mother with infant  (0:14, narrated; Erik Patel, Cornell University; Mpeg)
• Play  (1:10; Erik Patel, Cornell University; Mpeg)
• Scent Marking  (0:52; Erik Patel, Cornell University; Mpeg)
• Seed Predation  (1:14; Erik Patel, Cornell University; Mpeg)
• Self-grooming  (0:37; Erik Patel, Cornell University; Mpeg)
• Trouble in Lemur Land  (full length program; Vimeo: Erik Patel and Earth-Touch; 2011; Flash)

IMAGES

	Propithecus candidus Photo: Erik Patel
	Propithecus candidus Photo: Erik Patel
	Propithecus candidus Photo: Erik Patel
	Propithecus candidus Photo: Erik Patel
	Propithecus candidus Photo: Erik Patel
	Propithecus candidus Photo: Erik Patel
	Propithecus candidus Photo: Erik Patel
	Propithecus candidus Photo: Erik Patel
	Propithecus candidus Photo: Erik Patel
	Propithecus diadema Photo: Tomas Junek
	Propithecus diadema Photo: Tomas Junek
	Propithecus diadema Photo: Tomas Junek
	Propithecus diadema Photo: Tomas Junek
	Propithecus diadema Photo: Tomas Junek
	Propithecus edwardsi Photo: Michael Putnam
	Propithecus edwardsi Photo: Michael Putnam
	Propithecus edwardsi Photo: Michael Putnam
	Propithecus edwardsi Photo: Tomas Junek
	Propithecus perrieri Photo: Matthew Banks
	Propithecus perrieri Photo: Matthew Banks
	Propithecus tattersalli Photo: David Haring
	Propithecus tattersalli Photo: David Haring
	Propithecus tattersalli Photo: David Haring
	Propithecus tattersalli Photo: David Haring