Abstract
Although most colobines feed mainly on leaves and a few feed heavily on seeds, colobine digestive adaptations for folivory are thought to preclude the high use of ripe fleshy fruits. In this long-term study of Semnopithecus vetulus nestor, the endemic western purple-faced langur of Sri Lanka, I investigated the feeding ecology and dietary flexibility for fruit feeding in 2 free-ranging groups (PT1 and R1) living in human-modified environments with abundant cultivated fruit, at Panadura and Piliyandala, for 19 mo and 13 mo respectively, using scan-sampling, vegetation enumeration, and phenological studies. In contrast to folivorous forest-living colobines, including other subspecies of Semnopithecus vetulus, my focal groups used more fruit (>50%) than foliage (PT1: 36%; R1: 34%). Both groups used many plant species (PT1 115; R1 59), but selected their food species, fruits over leaves, and young leaves over mature leaves. Fruit use was independent of young leaf availability. Notably, 78.4% and 83.4% of fruits consumed by PT1 and R1 were fleshy and human-edible, most of which were ripening or ripe (PT1: 72.4%; R1: 94.8%). The main fruit for both groups was Artocarpus heterophyllus (Moraceae; jakfruit), a cultivar with fleshy fruit. These findings differ from previous understanding of colobine diets. I suggest that environmental factors, such as the abundance and nature of available fruits, and the absence of arboreal-primate fruit competitors, could influence the use of ripe fleshy fruits by colobines strongly, highlighting the need to review the dietary and digestive flexibility of this group in changed and changing natural environments to formulate effective conservation action.
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References
Altmann, J. (1974). Observational study of behaviour: sampling methods. Behaviour, 49, 227–264.
Amerasinghe, F. P., Van Cuylenberg, B. W. B., & Hladik, C. M. (1971). Comparative histology of the alimentary tract of Ceylon primates in correlation with the diet. Ceylon Journal of Sciences (Biological Sciences), 9, 75–87.
Ananthasubramaniam, C. R., Menachery, M., & Chandrasekharan Nair, A. M. (1978). Nutritive value of Jack (Artocarpus heterophyllus, Lam) fruit waste for cattle. The Indian Journal of Nutrition and Dietetics, 15, 12–16.
Bauchop, T. (1978). The significance of micro-organisms in the stomach of non-human primates. World Review of Nutrition and Dietetics, 332, 198–212.
Bennett, E. L. (1983). The banded langur: Ecology of a colobine in a west Malaysian rain-forest. Ph.D. thesis, University of Cambridge.
Bennett, E. L., & Davies, A. G. (1994). The ecology of Asian colobines. In A. G. Davies & J. F. Oates (Eds.), Colobine monkeys: Their ecology, behaviour, and evolution (pp. 129–171). Cambridge: Cambridge University Press.
Bennett, E. L., & Sebastian, A. C. (1988). Social organization and ecology of proboscis monkeys (Nasalis larvatus) in mixed coastal forest in Sarawak. International Journal of Primatology, 9, 233–255.
Bobbio, F. O., El-dash, A. A., Bobbio, P. A., & Rodrigues, L. R. (1978). Isolation and characterization of the physicochemical properties of the starch of jackfruit seeds (Artocarpus heterophyllus). Cereal Chemistry, 55, 505–511.
Brandon-Jones, D., Eudey, A. A., Geissmann, T., Groves, C. P., Melnick, D. J., Morales, J. C., et al. (2004). Asian primate classification. International Journal of Primatology, 25, 97–164.
Brugiere, D., Gautier, J. P., Moungazi, A., & Gautier-Hion, A. (2002). Primate diet and biomass in relation to vegetation composition and fruiting phenology in a rain forest in Gabon. International Journal of Primatology, 23(5), 999–1024.
Caton, J. M. (1999). Digestive strategy of the Asian colobine genus Trachypithecus. Primates, 40, 311–325.
Chapman, C. A., Chapman, L. J., Bjorndal, K. A., & Onderdonk, D. A. (2002). Application of protein-to-fiber ratios to predict colobine abundance on different spatial scales. International Journal of Primatology, 23(2), 283–310.
Chivers, D. J. (1994). Functional anatomy of the gastrointestinal tract. In A. G. Davies & J. F. Oates (Eds.), Colobine monkeys: Their ecology, behaviour and evolution (pp. 205–257). Cambridge: Cambridge University Press.
Clutton-Brock, T. H. (1975). Feeding behaviour of red colobus and black and white colobus in East Africa. Folia Primatologica, 23, 165–207.
Curtin, S. H., & Chivers, D. J. (1978). Leaf-eating primates of Peninsular Malaysia: the siamang and the dusky leaf-monkey. In G. G. Montgomery (Ed.), The ecology of arboreal folivores (pp. 441–464). Washington, DC: Smithsonian Institution Press.
Dasilva, G. L. (1994). Diet of Colobus polykomos on Tiwai Island: selection of food in relation to its seasonal abundance and nutritional quality. International Journal of Primatology, 15, 655–668.
Davies, A. G. (1991). Seed-eating by red leaf monkeys (Presbytis rubicunda) in a dipterocarp forest of northern Borneo. International Journal of Primatology, 12, 119–144.
Davies, A. G., Oates, J. F., & Dasilva, G. L. (1999). Patterns of frugivory in three West African colobine monkeys. International Journal of Primatology, 20, 327–357.
Dela, J. D. S. (1998). The ecology and social biology of a selected population of the western purple-faced leaf monkey (Trachypithecus vetulus nestor = Presbytis senex nestor). Ph.D. thesis, University of Peradeniya.
Dela, J. D. S. (2007). Seasonal food use strategies of Semnopithecus vetulus nestor, at Panadura and Piliyandala, Sri Lanka. International Journal of Primatology, 28(3), 607–626.
Dela, J. D. S. (in press). Impact of monkey-human relationships on Semnopithecus vetulus nestor in human modified environments. Journal of the National Science Foundation of Sri Lanka.
Deraniyagala, P. E. P. (1955). A new race of leaf monkey from Ceylon. Spolia Zeylanica, XXVII(11), 293–294.
Dew, J. L. (2005). Foraging, food choice, and food processing by sympatric ripe-fruit specialists: Lagothrix lagotricha poeppigii and Ateles belzebuth belzebuth. International Journal of Primatology, 26(5), 1107–1135.
Estrada, A. (1984). Resource use by howler monkeys (Alouatta palliata) in the rain forest of Los Tuxlas, Veracruz, Mexico. International Journal of Primatology, 5, 105–131.
Fashing, P. J. (2001). Feeding ecology of guerezas in the Kakamega forest, Kenya: the importance of Moraceae fruit in their diet. International Journal of Primatology, 22(4), 579–609.
Fashing, P. J., Dierenfeld, E. S., Christopher, B., & Mowry, C. B. (2007). Influence of plant and soil chemistry on food selection, ranging patterns, and biomass of Colobus guereza in Kakamega Forest, Kenya. International Journal of Primatology, 28(3), 673–703.
Freeland, W. J., & Janzen, D. H. (1974). Strategies in herbivory by mammals: the role of plant secondary compounds. American Naturalist, 108, 269–289.
Glander, K. E. (1975). Habitat description and resource utilization: A preliminary report on mantled howling monkey ecology. In R. H. Tuttle (Ed.), Socioecology and psychology of primates (pp. 37–57). The Hague: Mouton and Co.
Gunatilleke, I. A. U. N., & Gunatilleke, C. V. S. (1991). Threatened woody endemics of the wet lowlands of Sri Lanka and their conservation. Biological Conservation, 55, 17–35.
Gurmaya, K. J. (1986). Ecology and behavior of Presbytis thomasi in Northern Sumatra. Primates, 27, 151–172.
Hill, W. C. O. (1934). A monograph on the purple-faced leaf monkeys (Pithecus vetulus). Ceylon Journal of Science (B), xix (PT1), 23–88.
Hladik, C. M. (1977). A comparative study of the feeding strategies of two sympatric species of leaf monkeys: Presbytis senex and Presbytis entellus. In T. H. Clutton-Brock (Ed.), Primate ecology: Studies of feeding and ranging behaviour in lemurs, monkeys and apes (pp. 323–353). London: Academic Press.
Hoang, M. D., Baxter, G. S., & Page, M. J. (2009). Diet of Pygathrix nigripes in southern Vietnam. International Journal of Primatology, 30, 15–28.
Janzen, D. H. (1978). Complications in interpreting the chemical defences of trees against tropical arboreal plant-eating vertebrates. In G. G. Montgomery (Ed.), The ecology of arboreal folivores (pp. 73–85). Washington, DC: Smithsonian Institution Press.
Kay, R. N. B., & Davies, A. G. (1994). Digestive physiology. In A. G. Davies & J. F. Oates (Eds.), Colobine monkeys: Their ecology, behaviour and evolution (pp. 229–249). Cambridge: Cambridge University Press.
Kool, K. M. (1993). The diet and feeding behavior of the silver leaf monkey (Trachypithecus auratus sondaicus) Indonesia. International Journal of Primatology, 14, 667–670.
Lehner, P. M. (1979). Handbook of ethological methods. Garland Series in Ethology. New York: Garland STPM Press.
Li, Z., Wei, Y., & Rogers, E. (2003). Food choice of white-headed langurs in Fusui, China. International Journal of Primatology, 24, 1189–1205.
Maisels, F., Gautier-Hion, A., & Gautier, J. P. (1994). Diets of two sympatric colobines in Zaire: more evidence on seed-eating in forests on poor soils. International Journal of Primatology, 15, 681–701.
Mallika, G. V. (1991). Applied chemical studies on rubber seed to support its industrial utilization. M.Phil thesis, University of Sri Jayawardenapura, Nugegoda.
Marsh, C. W. (1981). Diet choice among red colobus (Colobus badius rufomitratus) on the Tana River, Kenya. Folia Primatologica, 35, 147–178.
Matsuda, I., Tuuga, A., & Higashi, S. (2009). The feeding ecology and activity budget of proboscis monkeys. American Journal of Primatology, 71, 1–15.
McKey, D. B. (1978). Soils, vegetation, and seed-eating by black colobus monkeys. In G. G. Montgomery (Ed.), The ecology of arboreal folivores (pp. 423–438). Washington, DC: Smithsonian Institution Press.
McKey, D. B., Gartlan, J. S., Waterman, P. G., & Choo, G. M. (1981). Food selection by black colobus monkeys (Colobus satanas) in relation to food chemistry. Biological Journal of the Linnaean Society, 16, 115–146.
Milton, K. (1979). Factors influencing leaf choice by howler monkeys: a test of some hypotheses of food selection by generalist herbivores. American Naturalist, 114, 362–378.
Milton, K. (1980). The foraging strategy of howler monkeys: A study in primate economics. New York: Columbia University Press.
Milton, K. (1981). Food choice and digestive strategies by two sympatric primate species. American Naturalist, 117, 496–505.
Mittermeier, R. A., Ratsimbazafy, J., Rylands, A. B., Williamson, L., Oates, J. F., Mbora, D., et al. (2005). Primates in peril: the World’s 25 Most Endangered Primates 2006–2008. Primate Conservation, 22, 1–40.
Moncur, M. W. (1985). Floral ontogeny of the jackfruit Artocarpus heterophyllus. Lam (Moraceae). Australian Journal of Botany, 33, 585–593.
Mowry, C. B., Decker, B. S., & Shure, D. J. (1996). The role of phytochemistry in dietary choices of Tana River red colobus monkeys (Procolobus badius rufomitratus). International Journal of Primatology, 17, 63–84.
NARESA (1991). Natural resources of Sri Lanka: Conditions and trends. In M. F. Baldwin (Ed.), Keels Business Systems, Education Centre. Colombo.
Oates, J. F. (1988). The diet of the olive colobus monkey, Procolobus verus, in Sierra Leone. International Journal of Primatology, 9, 457–478.
Oates, J. F., & Davies, A. G. (1994). What are the colobines? In A. G. Davies & J. F. Oates (Eds.), Colobine monkeys: Their ecology, behaviour and evolution (pp. 1–9). Cambridge: Cambridge University Press.
Oates, J. F., Waterman, P. G., & Choo, G. M. (1980). Food selection by the south Indian leaf-monkey, Presbytis johnii, in relation to leaf chemistry. Oecologica (Berlin), 45, 45–56.
Oxnard, C. E. (1969). A note on the ruminant-like digestion of langurs. Laboratory Primate Newsletter, 8, 24–25.
Robinson, J. G. (1986). Seasonal variation in use of time and space by the wedge-capped capuchin monkey Cebus olivaceus: implications for foraging theory. Smithsonian Contribution to Zoology, 431.
Rudran, R. (1970). Aspects of ecology of two sub-species of purple-faced langurs (Presbytis senex). M.Sc. thesis, University of Ceylon.
Rudran, R. (1978). Socioecology of the blue-monkey (Ceropithecus mitis stuhlmanni) of the Kibale Forest, Uganda. Smithsonian Contribution to Zoology, 249.
Ruhiyat, Y. (1983). Socio-ecological study of Presbytis aygula in West Java. Primates, 24(3), 344–359.
Senaratna, L. K. (2001). A checklist of the flowering plants of Sri Lanka. Sri Lanka: National Science Foundation.
Solanki, G. S. K., Kumar, A., & Shama, B. K. (2008). Feeding ecology of Trachypithecus pileatus in India. The diet of the capped langur (Presbytis pileata) in a moist deciduous forest in Bangladesh. International Journal of Primatology, 12, 199–216.
Stanford, C. B. (1991). The diet of the capped langur (Presbytis pileata) in a moist deciduous forest in Bangladesh. International Journal of Primatology, 12(3), 199–121.
Stevenson, P. R. (2004). Fruit choice by woolly monkeys in Tinigua National Park, Colombia. International Journal of Primatology, 25(2), 367–381.
Struhsaker, T. T. (1975). The red colobus monkey. Chicago: University of Chicago Press.
Sulit, J. I., & Ganaban, E. V. (1968). Studies of the utilization of non-edible portion of ripe nangka (Artocarpus integrifolia) fruit for jelly-making. Araneta Journal of Agriculture, 15, 213–228.
Ungar, P. S. (1995). Fruit preferences of four sympatric primate species at Ketambe, Northern Sumatra, Indonesia. International Journal of Primatology, 16(2), 221–224.
Wasserman, M. D., & Chapman, C. A. (2003). Determinants of colobine monkey abundance: the importance of food energy, protein and fibre content. Journal of Animal Ecology, 72, 650–659.
Waterman, P. G., & Kool, K. M. (1994). Colobine food selection and plant chemistry. In A. G. Davies & J. F. Oates (Eds.), Colobine monkeys: Their ecology, behaviour and evolution (pp. 125–284). Cambridge: Cambridge University Press.
Wijesinghe, L.C. A. de S., Gunatilleke, I. U. A. N., Jayawardene, S. D. G., Kotagama, S. W., & Gunatilleke, C. V. S. (1993). Biological conservation in Sri Lanka. A status report. Colombo: IUCN Sri Lanka.
Wong, S. N. P., Saj, T. L., & Sicotte, P. (2006). Comparison of habitat quality and diet of Colobus vellerosus in forest fragments in Ghana. Primates, 47, 365–373.
Yeager, C. P. (1989). Feeding ecology of the proboscis monkey (Nasalis larvatus). International Journal of Primatology, 10, 453–497.
Zhou, Q., Wei, F., Li, M., Huang, C., & Luo, B. (2006). Diet and food choice of Trachypithecus francoisi in the Nonggang Nature Reserve, China. International Journal of Primatology, 27(5), 1441–1460.
Acknowledgments
Financial support for the feeding study was provided by the Natural Resources Energy and Science Authority of Sri Lanka (presently the National Science Foundation) through Grant MAB/85/1. I am deeply grateful to the late Mr. L. de Alwis and Prof S. W. Kotagama for the help given for me to secure funds and their support. I offer special thanks to my chief Ph.D. supervisor, Dr. W. P. J. Dittus, for advice and critical comments, and to Mr. Leslie Wijesinghe, the late Prof. W. R. Breckenridge, and the late Dr. R. P. Jayawardena for their encouragement when it was most needed. I also thank the Public Trustee and the manager and staff of the Regidale Estate for permission to conduct this work at Piliyandala, and all householders who allowed me to conduct this research. I thank my dedicated field assistants: Ms. M. L. Soma Perera, Jane Nona, Aslin, and Badra. Special thanks are due to Ms. Neela de Zoysa-Simon for identification of plant specimens; Ms. Gayathree Jayasinghe for statistical advice and data entry; Ms. Piyandani Dissanayake, Ms. Anne Moldrich, and the late Ms. Vasumathi Somasundaram for help with data entry; and Ms. Elaine Wijesinha for patient help with checking data tables. I am grateful for comments in relation to future publications by my Ph.D. examiner, Dr. Elizabeth Bennett, and for comments on this paper from Dr. Peter Fashing and an anonymous reviewer. I thank Dr. Joanna Setchell for very constructive editorial suggestions. I also thank Primate Conservation Incorporated, The Ministry of Environment (Sri Lanka), and MathHydropower (Pvt) Limited for supporting the range survey of Semnopithecus vetulus nestor, and the Forest Department of Sri Lanka for help with forest surveys, which provided valuable insight on feeding habits throughout the range of the western purple-faced langur.
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Jinie D. S. Dela is a visiting academic of the Open University of Sri Lanka.
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Dela, J.D.S. Western Purple-faced Langurs (Semnopithecus vetulus nestor) Feed on Ripe and Ripening Fruits in Human-modified Environments in Sri Lanka. Int J Primatol 33, 40–72 (2012). https://doi.org/10.1007/s10764-011-9538-3
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DOI: https://doi.org/10.1007/s10764-011-9538-3