Silky Sifaka Lemur
Propithecus candidus
One of the 25 most endangered Primates
The Silky Sifaka is a rare species of lemur found in northeastern Madagascar. It is listed as one of the 25 most endangered primates in the world. This species is being studied by researcher Erik Patel. We’ve created this page to help highlight his work on silky sifakas and share the video that Sharon Pieczenik created on the same topic.
Angels of the Forest: Silky Sifaka Lemurs of Madagascar
In this documentary, produced by Sharon Pieczenik and WYCTL Media, Erik Patel, PhD Candidate at Cornell University, discusses his efforts to save silky sifaka lemurs in Madagascar. Ninety-eight percent of Madagascar’s mammals, including the rare silky sifaka lemurs, exist nowhere else on Earth. Because of their white fur and their amazing ability to fly through the forest, silky sifaka lemurs are called “angels of the forest.” If silky sifaka lemurs were to disappear from Madagascar, they would disappear from the world. International scientists and local Malagasy conservationists are fighting for the survival of this exceptional species and its irreplaceable habitat.
More about the Filmmaker: Sharon Pieczenik
Sharon is a recent graduate of Montana State University’s Science and Natural History Filmmaking department, a program which takes scientists and trains them to become wildlife filmmakers. Sharon has produced films on polar bears as well as wildlife in Madagascar. She was a contestant of the Discovery Channel’s Reel Race and was second camera for Dateline.
Silky Sifaka Biology
What do they eat?
Most of the time silky sifakas are folivorous meaning they eat primarily leaves, flowers, and other foliage of over 100 types of trees and vines. They are also seed predators which means they often prefer to eat the hard inner seed rather the flesh of the fruit. But when fruits are ripe, they will travel extra long distances to feed on ripe fruit. Though they live in the trees, occasionally they actually come to the ground to feed on dirt and the immature flowers of some parasitic plants.
What eats them?
The only documented natural predator of the silky sifaka is the fossa, a medium-sized, weasel-like carnivore only found in Madagascar. Silky sifakas are sometimes hunted for food by local residents since there is no local taboo prohibiting lemur hunting where they are found. Sometimes silky sifakas emit loud alarm calls to large raptors, though no predation attempts have ever been observed. Raptors may pose a danger to infant silkies. Several of the largest raptors which posed the greatest threat to silky sifakas recently went extinct in Madagascar.
Where do they live?
Silky Sifakas live in moist forests in a small region of northeastern Madagascar. Most of their of population is found in the high altitude regions (above 700 m of elevation) in Marojejy National Park and Anjanaharibe-Sud Special Reserve. Some are also found in the Makira Forest Protected Area. Silky sifakas are in critical danger of extinction due to habitat loss caused mainly by slash-and-burn agriculture for rice production as well as illegal rosewood logging. Hunting by humans is a growing problem. There is no local taboo against hunting silky sifakas. Silky sifakas are among the top 25 most critically endangered primates in the world and the top 4 rarest lemurs in Madagascar out of over 100 types of lemurs. The work of Erik Patel and others in Madagascar will hopefully be enough to save these amazing creatures.
Text Edited by Eric Patel
Web links
Researcher Erik Patel’s Facts about the Silky Sifakas
University of Wisconsin – Silky Sifaka Fact Sheet
Useful Texts (Citations via Erik Patel)
- Andrianandrasana, LH; Patel, ER and 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 Abstracts. Ithala, South Africa.
- Duckworth, J.W ., Evans, M.I ., Hawkins, A. F. A , Safford, R.J ., and Wilkinson, R.J . 1995. The lemurs of Marojejy Strict Nature Reserve, Madagascar: A status overview with notes on ecology and threats.International Journal of Primatology 16(3): 545 – 559.
- Garbutt N. 2007. Mammals of Madagascar : A Complete Guide. London: A&C Black. 2007.
- Goodman, S.M., Raherilalao, M.J., Rakotomalala, D., Raselimanana, A., Schütz, H., and Soarimalala, V., 2003. Les Lémuriens. In: Nouveaux résultats d’inventaires biologiques faisant référence à l’altitude dans la région des massifs montagneux de Marojejy et d’Anjanaharibe-Sud, S.M. Goodman and L. Wilmé (eds.). Recherchespour le Développement, série sciences biologiques no. 19, Centre d’Information et de Documentation Scientifique et Technique, Antananarivo, pp. 279–286.
- Groves, C.P. 2001. Primate Taxonomy. Smithsonian Institution, Washington D.C.
- Guillaumet, J.L., Betsch, J.M., Blanc, C., Morat, P., and Peyrieras, A., and Paulian, R. 1975. Etude des ecosystems montagnards dansla region malgache. III. Le Marojezy. IV. L’itremo et l’ibity. Geomorphologie, climatologie, faune et flore (Campagne RCP 225, 1972 – 1973). Bulletin du Museum National d’Histoire Naturelle (Paris), serie 3, 309 (Ecologie Generale), 25: 27 – 67.
- Humbert, H. 1955. Une merveille de la nature a Madagascar. Premiere exploration botanique du massif du Marojejy, et de ses satellites. Memoires de L’Institut Scientifique de Madagascar, serie B, 6: 1 – 210.
- Irwin MT. 2006. Ecologically enigmatic lemurs: the sifakas of the eastern forests (Propithecus candidus, P. diadema, P. edwardsi, P. perrieri, and P. tattersalli) In Lemurs : Ecology and Adaptation edited by Gould L Sauther ML. New York: Springer. 2006. Pgs: 305-326.
- Kelley, E . and Mayor, M.I . 2002. Preliminary study of the silky sifaka (Propithecus diadema candidus) in north-east Madagascar. Lemur News 7: 16 – 18.
- Lehman, S.M ., Mayor, M ., and Wright, P.C . 2005. Ecogeographic size variations in sifakas: a test of the resource seasonality and resource quality hypotheses. American Journal of Physical Anthropology 126(3): 318 – 328.
- Mayor, M.I., Sommer, J.A., Houck, M.L., Zaonarivelo, J.R., Wright, P.C., Ingram, C., Engel, S.R., and Louis, E.E. Jr. 2004. Specific status of Propithecus spp. International Journal of Primatology 25(4): 875 – 900.
- Milne-Edwards, A. and Grandidier, A. 1875. L’Histoire Politique, Physique et Naturelle de Madagascar: Histoire Naturelle des Mammifères, Paris, Impr. nationale.
- Mittermeier, R.A.; Konstant, W.R.; Hawkins, F.; Louis, E.E.; Langrand, O.; Ratsimbazafy, J.; Rasoloarison, R.; Ganzhorn, J.U.; Rajaobelina, S.; Tattersall, I.; Meyers, D.M. 2006. Lemurs of Madagascar. Conservational International, Washington D.C.
- Nicoll, M.E., and Langrand, O. 1989. Madagascar: Revue de la conservation et des aires protégées. World Wide Fund for Nature, Gland, Switzerland.
- Nielsen M and Patel ER. 2008. The role of taste preference and wealth in bushmeat hunting in villages adjacent to Marojejy National Park, Madagascar. Primate Eye. 2008. 96(Sp CD-ROM iss – IPS 2008). Abst #616
- Owren MJ and Patel ER. 2008. A little of this, a lot of that: specificity and variability in nonhuman primate vocal repertoires. Primate Eye. 2008. 96(Sp CD-ROM iss – IPS 2008). Abst #742
- Patel, E.R ., Coke, C.S ., 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. American Journal of Primatology 60(1): 71.
- Patel, E.R ., Coke, C.S ., Ritchie, A ., and 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. American Journal of Primatology 60(1): 71-72.
- Patel, E.R . 2005. Silky sifaka predation (Propithecus candidus) by a fossa (Cryptoprocta ferox). Lemur News 10: 25 – 27.
- Patel, ER, Anderson, JD, and Owren, MJ. 2005a. Sex differences in the acoustic structure of an alarm vocalization in a monomorphic primate: Wild silky sifakas (Propithecus candidus) of Northeastern Madagascar. American Journal of Primatology 66(Suppl 1): 46-47.
- Patel, E.R ., Anderson, J.D ., Irwin, M.T ., and Owren, M.J . 2005b. Quantifying the vocal repertoire of wild adult diademed sifakas (Propithecus diadema diadema) in Madagascar. American Journal of Primatology 66(1): 48.
- Patel, E.R ., Marshall, J.J ., and Parathian, H . 2005c. Silky sifaka (Propithecus candidus) conservation education in northeastern Madagascar. Laboratory Primate Newsletter 44(3): 8 – 11.
- Patel, E.R . 2006a. Scent-marking in wild silky sifakas (Propithecus candidus) in Madagascar: sex differences and seasonal effects in usage and response across multiple scent-mark types. International Journal of Primatology 27(1): Abstract #496.
- Patel, E.R . 2006b. Activity budget, ranging, and group size in silky sifakas (Propithecus candidus). Lemur News 11: 42 – 45.
- Patel, E.R ., Anderson, J.D ., and Owren, M.J . 2006. Exploring the function of “Zzuss” alarm vocalizations in wild silky sifakas (Propithecus candidus): moderate evidence for individual distinctiveness. International Journal of Primatology 27(1): Abstract #504.
- Patel ER, Meyers D, and Hawkins F (2007). Silky Sifaka, Propithecus candidus, 1871. In: Primates in Peril: The World’s 25 Most Endangered Primates 2006-2008, R. A. Mittermeier et al. (compilers), In: R. A. Mittermeier, J. Ratsimbazafy, A. B. Rylands, L. Williamson, J. F. Oates, D. Mbora, J. U. Ganzhorn, E. Rodríguez-Luna, E. Palacios, E. W. Heymann, M. C. M. Kierulff, L. Yongcheng, J. Supriatna, C. Roos, S. Walker and J. M. Aguiar (compilers), Primates in Peril: The World’s 25 Most Endangered Primates 2006-2008, pp.11-12, 26-27. Primate Conservation (22): 1-40.
- Patel, E.R . 2007a. Non-maternal infant care in wild Silky sifakas (Propithecus candidus). Lemur News 12: 39 – 42.
- Patel, E.R. 2007b. Logging of rare rosewood and palisandre (Dalbergia spp.) within Marojejy National Park, Madagascar. Madagascar Conservation and Development 2: 11-16.
- Patel, E.R. and Andrianandrasana, L.H. 2008. Low elevation silky sifakas (Propithecus candidus) in the Makira Conservation Site at Andaparaty-Rabeson: Ranging, demography, and possible sympatry with red ruffed lemurs (Varecia rubra). Lemur News 13: 18 – 22.
- Patel ER and Girard-Buttoz C. 2008. Non-nutritive tree gouging in wild Milne-Edwards’ sifakas (Propithecus edwardsi): description and potential communicative functions. Primate Eye 96(Sp CD-ROM iss – IPS 2008). Abst #283
- Petter, J.J. and Charles-Dominique, P. 1979. Vocal communication in prosimians. In The Study of Prosimian Behavior edited by G.A. Doyle and R.D. Martin. Academic Press. Pgs: 247-305.
- Queslin, E. and Patel, E.R. 2008. A preliminary study of wild silky sifaka (Propithecus candidus) diet, feeding ecology, and habitat use in Marojejy National Park, Madagascar. International Primatological Society. Abstract #143.
- Rasolofoson, D., Rakotondratsimba, G ., Rakotonirainy, O ., Rakotozafy, L.M.A ., Ratsimbazafy, J.H ., Rabetafika, L ., Randrianarison, R.M . 2007. Influence of human pressure on lemur groups on the Makira Plateau, Maroantsetra, Madagascar. Madagascar Conservation and Development 2: 21 – 27.
- Richard, A. 2003. Propithecus, sifakas. In The Natural History of Madagascar edited by Goodman, SM and Benstead JP. Chicago: Univ Chicago Press. 2003. Pgs: 1344-1348.
- Ritchie, A . and Patel, E.R . 2006. The existence and potential function of “totem-tree” scent-marking in silky sifakas (Propithecus candidus). International Journal of Primatology 27(1): Abstract #361.
- Schmid, J. and Smolker, R. 1998. Lemurs of the Reserve Speciale d’Anjanaharibe-Sud, Madagascar. Fieldiana Zoology 90: 227 – 240.
- Sterling, E . and McFadden, K . 2000. Rapid census of lemur populations in the Parc National de Marojejy, Madagascar. Fieldiana Zoology 97: 265 – 274.
- Sussman, RW. 2000. Primate Ecology and Social Structure. Val. 1 : Lorises, Lemurs, and Tarsiers. Pearson Custom Publishing. Heights,MA.
- Tattersall, I. 1982. The Primates of Madagascar. New York: Columbia University Press.
- Tattersall, I. 2007. Madagascar’s lemurs: cryptic diversity or taxonomic inflation? Evolutionary Anthropology 16(1): 12 – 23.
- Wilme, L . and Callmander, M.W . 2006. Relic populations of primates:sifakas. Lemur News 11: 24 – 31.
Related Topics
One of the 25 most endangered Primates
The Silky Sifaka is a rare species of lemur found in northeastern Madagascar. It is listed as one of the 25 most endangered primates in the world. This species is being studied by researcher Erik Patel. We’ve created this page to help highlight his work on silky sifakas and share the video that Sharon Pieczenik created on the same topic.
Angels of the Forest: Silky Sifaka Lemurs of Madagascar
In this documentary, produced by Sharon Pieczenik and WYCTL Media, Erik Patel, PhD Candidate at Cornell University, discusses his efforts to save silky sifaka lemurs in Madagascar. Ninety-eight percent of Madagascar’s mammals, including the rare silky sifaka lemurs, exist nowhere else on Earth. Because of their white fur and their amazing ability to fly through the forest, silky sifaka lemurs are called “angels of the forest.” If silky sifaka lemurs were to disappear from Madagascar, they would disappear from the world. International scientists and local Malagasy conservationists are fighting for the survival of this exceptional species and its irreplaceable habitat.
More about the Filmmaker: Sharon Pieczenik
Sharon is a recent graduate of Montana State University’s Science and Natural History Filmmaking department, a program which takes scientists and trains them to become wildlife filmmakers. Sharon has produced films on polar bears as well as wildlife in Madagascar. She was a contestant of the Discovery Channel’s Reel Race and was second camera for Dateline.
Silky Sifaka Biology
What do they eat?
Most of the time silky sifakas are folivorous meaning they eat primarily leaves, flowers, and other foliage of over 100 types of trees and vines. They are also seed predators which means they often prefer to eat the hard inner seed rather the flesh of the fruit. But when fruits are ripe, they will travel extra long distances to feed on ripe fruit. Though they live in the trees, occasionally they actually come to the ground to feed on dirt and the immature flowers of some parasitic plants.
What eats them?
The only documented natural predator of the silky sifaka is the fossa, a medium-sized, weasel-like carnivore only found in Madagascar. Silky sifakas are sometimes hunted for food by local residents since there is no local taboo prohibiting lemur hunting where they are found. Sometimes silky sifakas emit loud alarm calls to large raptors, though no predation attempts have ever been observed. Raptors may pose a danger to infant silkies. Several of the largest raptors which posed the greatest threat to silky sifakas recently went extinct in Madagascar.
Where do they live?
Silky Sifakas live in moist forests in a small region of northeastern Madagascar. Most of their of population is found in the high altitude regions (above 700 m of elevation) in Marojejy National Park and Anjanaharibe-Sud Special Reserve. Some are also found in the Makira Forest Protected Area. Silky sifakas are in critical danger of extinction due to habitat loss caused mainly by slash-and-burn agriculture for rice production as well as illegal rosewood logging. Hunting by humans is a growing problem. There is no local taboo against hunting silky sifakas. Silky sifakas are among the top 25 most critically endangered primates in the world and the top 4 rarest lemurs in Madagascar out of over 100 types of lemurs. The work of Erik Patel and others in Madagascar will hopefully be enough to save these amazing creatures.
Text Edited by Eric Patel
Web links
Researcher Erik Patel’s Facts about the Silky Sifakas
University of Wisconsin – Silky Sifaka Fact Sheet
Useful Texts (Citations via Erik Patel)
- Andrianandrasana, LH; Patel, ER and 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 Abstracts. Ithala, South Africa.
- Duckworth, J.W ., Evans, M.I ., Hawkins, A. F. A , Safford, R.J ., and Wilkinson, R.J . 1995. The lemurs of Marojejy Strict Nature Reserve, Madagascar: A status overview with notes on ecology and threats.International Journal of Primatology 16(3): 545 – 559.
- Garbutt N. 2007. Mammals of Madagascar : A Complete Guide. London: A&C Black. 2007.
- Goodman, S.M., Raherilalao, M.J., Rakotomalala, D., Raselimanana, A., Schütz, H., and Soarimalala, V., 2003. Les Lémuriens. In: Nouveaux résultats d’inventaires biologiques faisant référence à l’altitude dans la région des massifs montagneux de Marojejy et d’Anjanaharibe-Sud, S.M. Goodman and L. Wilmé (eds.). Recherchespour le Développement, série sciences biologiques no. 19, Centre d’Information et de Documentation Scientifique et Technique, Antananarivo, pp. 279–286.
- Groves, C.P. 2001. Primate Taxonomy. Smithsonian Institution, Washington D.C.
- Guillaumet, J.L., Betsch, J.M., Blanc, C., Morat, P., and Peyrieras, A., and Paulian, R. 1975. Etude des ecosystems montagnards dansla region malgache. III. Le Marojezy. IV. L’itremo et l’ibity. Geomorphologie, climatologie, faune et flore (Campagne RCP 225, 1972 – 1973). Bulletin du Museum National d’Histoire Naturelle (Paris), serie 3, 309 (Ecologie Generale), 25: 27 – 67.
- Humbert, H. 1955. Une merveille de la nature a Madagascar. Premiere exploration botanique du massif du Marojejy, et de ses satellites. Memoires de L’Institut Scientifique de Madagascar, serie B, 6: 1 – 210.
- Irwin MT. 2006. Ecologically enigmatic lemurs: the sifakas of the eastern forests (Propithecus candidus, P. diadema, P. edwardsi, P. perrieri, and P. tattersalli) In Lemurs : Ecology and Adaptation edited by Gould L Sauther ML. New York: Springer. 2006. Pgs: 305-326.
- Kelley, E . and Mayor, M.I . 2002. Preliminary study of the silky sifaka (Propithecus diadema candidus) in north-east Madagascar. Lemur News 7: 16 – 18.
- Lehman, S.M ., Mayor, M ., and Wright, P.C . 2005. Ecogeographic size variations in sifakas: a test of the resource seasonality and resource quality hypotheses. American Journal of Physical Anthropology 126(3): 318 – 328.
- Mayor, M.I., Sommer, J.A., Houck, M.L., Zaonarivelo, J.R., Wright, P.C., Ingram, C., Engel, S.R., and Louis, E.E. Jr. 2004. Specific status of Propithecus spp. International Journal of Primatology 25(4): 875 – 900.
- Milne-Edwards, A. and Grandidier, A. 1875. L’Histoire Politique, Physique et Naturelle de Madagascar: Histoire Naturelle des Mammifères, Paris, Impr. nationale.
- Mittermeier, R.A.; Konstant, W.R.; Hawkins, F.; Louis, E.E.; Langrand, O.; Ratsimbazafy, J.; Rasoloarison, R.; Ganzhorn, J.U.; Rajaobelina, S.; Tattersall, I.; Meyers, D.M. 2006. Lemurs of Madagascar. Conservational International, Washington D.C.
- Nicoll, M.E., and Langrand, O. 1989. Madagascar: Revue de la conservation et des aires protégées. World Wide Fund for Nature, Gland, Switzerland.
- Nielsen M and Patel ER. 2008. The role of taste preference and wealth in bushmeat hunting in villages adjacent to Marojejy National Park, Madagascar. Primate Eye. 2008. 96(Sp CD-ROM iss – IPS 2008). Abst #616
- Owren MJ and Patel ER. 2008. A little of this, a lot of that: specificity and variability in nonhuman primate vocal repertoires. Primate Eye. 2008. 96(Sp CD-ROM iss – IPS 2008). Abst #742
- Patel, E.R ., Coke, C.S ., 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. American Journal of Primatology 60(1): 71.
- Patel, E.R ., Coke, C.S ., Ritchie, A ., and 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. American Journal of Primatology 60(1): 71-72.
- Patel, E.R . 2005. Silky sifaka predation (Propithecus candidus) by a fossa (Cryptoprocta ferox). Lemur News 10: 25 – 27.
- Patel, ER, Anderson, JD, and Owren, MJ. 2005a. Sex differences in the acoustic structure of an alarm vocalization in a monomorphic primate: Wild silky sifakas (Propithecus candidus) of Northeastern Madagascar. American Journal of Primatology 66(Suppl 1): 46-47.
- Patel, E.R ., Anderson, J.D ., Irwin, M.T ., and Owren, M.J . 2005b. Quantifying the vocal repertoire of wild adult diademed sifakas (Propithecus diadema diadema) in Madagascar. American Journal of Primatology 66(1): 48.
- Patel, E.R ., Marshall, J.J ., and Parathian, H . 2005c. Silky sifaka (Propithecus candidus) conservation education in northeastern Madagascar. Laboratory Primate Newsletter 44(3): 8 – 11.
- Patel, E.R . 2006a. Scent-marking in wild silky sifakas (Propithecus candidus) in Madagascar: sex differences and seasonal effects in usage and response across multiple scent-mark types. International Journal of Primatology 27(1): Abstract #496.
- Patel, E.R . 2006b. Activity budget, ranging, and group size in silky sifakas (Propithecus candidus). Lemur News 11: 42 – 45.
- Patel, E.R ., Anderson, J.D ., and Owren, M.J . 2006. Exploring the function of “Zzuss” alarm vocalizations in wild silky sifakas (Propithecus candidus): moderate evidence for individual distinctiveness. International Journal of Primatology 27(1): Abstract #504.
- Patel ER, Meyers D, and Hawkins F (2007). Silky Sifaka, Propithecus candidus, 1871. In: Primates in Peril: The World’s 25 Most Endangered Primates 2006-2008, R. A. Mittermeier et al. (compilers), In: R. A. Mittermeier, J. Ratsimbazafy, A. B. Rylands, L. Williamson, J. F. Oates, D. Mbora, J. U. Ganzhorn, E. Rodríguez-Luna, E. Palacios, E. W. Heymann, M. C. M. Kierulff, L. Yongcheng, J. Supriatna, C. Roos, S. Walker and J. M. Aguiar (compilers), Primates in Peril: The World’s 25 Most Endangered Primates 2006-2008, pp.11-12, 26-27. Primate Conservation (22): 1-40.
- Patel, E.R . 2007a. Non-maternal infant care in wild Silky sifakas (Propithecus candidus). Lemur News 12: 39 – 42.
- Patel, E.R. 2007b. Logging of rare rosewood and palisandre (Dalbergia spp.) within Marojejy National Park, Madagascar. Madagascar Conservation and Development 2: 11-16.
- Patel, E.R. and Andrianandrasana, L.H. 2008. Low elevation silky sifakas (Propithecus candidus) in the Makira Conservation Site at Andaparaty-Rabeson: Ranging, demography, and possible sympatry with red ruffed lemurs (Varecia rubra). Lemur News 13: 18 – 22.
- Patel ER and Girard-Buttoz C. 2008. Non-nutritive tree gouging in wild Milne-Edwards’ sifakas (Propithecus edwardsi): description and potential communicative functions. Primate Eye 96(Sp CD-ROM iss – IPS 2008). Abst #283
- Petter, J.J. and Charles-Dominique, P. 1979. Vocal communication in prosimians. In The Study of Prosimian Behavior edited by G.A. Doyle and R.D. Martin. Academic Press. Pgs: 247-305.
- Queslin, E. and Patel, E.R. 2008. A preliminary study of wild silky sifaka (Propithecus candidus) diet, feeding ecology, and habitat use in Marojejy National Park, Madagascar. International Primatological Society. Abstract #143.
- Rasolofoson, D., Rakotondratsimba, G ., Rakotonirainy, O ., Rakotozafy, L.M.A ., Ratsimbazafy, J.H ., Rabetafika, L ., Randrianarison, R.M . 2007. Influence of human pressure on lemur groups on the Makira Plateau, Maroantsetra, Madagascar. Madagascar Conservation and Development 2: 21 – 27.
- Richard, A. 2003. Propithecus, sifakas. In The Natural History of Madagascar edited by Goodman, SM and Benstead JP. Chicago: Univ Chicago Press. 2003. Pgs: 1344-1348.
- Ritchie, A . and Patel, E.R . 2006. The existence and potential function of “totem-tree” scent-marking in silky sifakas (Propithecus candidus). International Journal of Primatology 27(1): Abstract #361.
- Schmid, J. and Smolker, R. 1998. Lemurs of the Reserve Speciale d’Anjanaharibe-Sud, Madagascar. Fieldiana Zoology 90: 227 – 240.
- Sterling, E . and McFadden, K . 2000. Rapid census of lemur populations in the Parc National de Marojejy, Madagascar. Fieldiana Zoology 97: 265 – 274.
- Sussman, RW. 2000. Primate Ecology and Social Structure. Val. 1 : Lorises, Lemurs, and Tarsiers. Pearson Custom Publishing. Heights,MA.
- Tattersall, I. 1982. The Primates of Madagascar. New York: Columbia University Press.
- Tattersall, I. 2007. Madagascar’s lemurs: cryptic diversity or taxonomic inflation? Evolutionary Anthropology 16(1): 12 – 23.
- Wilme, L . and Callmander, M.W . 2006. Relic populations of primates:sifakas. Lemur News 11: 24 – 31.
