Persistence of Trachypithecus geei (Mammalia: Primates: Cercopithecidae) in a rubber plantation in Assam, India

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Joydeep Shil
Jihosuo Biswas
Sudipta Nag
Honnavalli N. Kumara


Non-human primates are highly threatened as a result of habitat destruction, agricultural expansion, industrial development, large-scale build-ups and wildlife trafficking. Nearly 60% of all primates are threatened and many are found in habitats with some form of human modifications (e.g., croplands and plantations). The adaptability of primates to survive in human-modified habitats is thus a key to determine their persistence in anthropogenic landscapes. In this study, we examined the population number and age-sex composition of the ‘Endangered’ Golden Langur Trachypithecus geei in a rubber plantation in the Kokrajhar District in Assam, India in 2016, and compared with past data of the langur population and demographics from the same location to better understand the population dynamics, demographic characters and persistence of the Golden Langurs in the rubber plantation. In 2016, we recorded six groups of Golden Langurs totaling 78 individuals with a mean group size of 13.00±4.00SD. Of the total population, 10.29% were adult males, 41.18% were adult females, 32.35% were juveniles and 16.18% were infants. The overall population growth from 1997 to 2016 was estimated to be 5.54% per year. Habitat matrices of rubber plantations with natural forest patches are important in the fragmented landscape for the persistence of Golden Langur populations. They may also act as a corridor for the langurs to move between the fragments and as food resources, highlighting the importance of such matrices for the langurs outside protected areas. Population monitoring and ecological studies in such matrices would therefore be needed for the successful implementation of targeted management strategies for the conservation of these threatened langurs.

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Anderson, J., J.M. Rowcliffe & G. Cowlishaw (2007). Does the matrix matter? A forest primate in a complex agricultural landscape. Biological Conservation 135(2): 212–222.

Arroyo-Rodríguez, V., G.K. Pérez-Elissetche, J.D. Ordóñez-Gómez, A. González-Zamora, Ó.M. Chaves, S. Sánchez-López, C.A. Chapman, K. Morales-Hernández, M. Pablo-Rodríguez & G. Ramos-Fernández (2017). Spider monkeys in human-modified landscapes: the importance of the matrix. Tropical Conservation Science 10: 1940082917719788.

Asensio, N., V. Arroyo‐Rodríguez, J.C. Dunn & J. Cristóbal‐Azkarate (2009). Conservation value of landscape supplementation for howler monkeys living in forest patches. Biotropica 41(6): 768–773.

Bahuguna, V.K., M.H. Swaminath, S. Tripathi, T.P. Singh, V.R.S. Rawat & R.S. Rawat (2016). Revisiting forest types of India. International Forestry Review 18(2): 135–145.

Barthakur, M. (1986). Weather and Climate of North East India. The Northeast Geographer 18(1): 20–27.

Biswas, J. (2004). Ecology and social behaviour of golden langur (Trachypithecus geei) Khajuria, 1956). PhD thesis. Department of Zoology, Gauhati University, xi+232pp.

Boonratana, R. (2013). Fragmentation and its significance on the conservation of Proboscis Monkey (Nasalis larvatus) in the Lower Kinabatangan, Sabah (North Borneo), pp. 459–475. In: Marsh, L. & C. Chapman (eds.). Primates in Fragments. Developments in Primatology: Progress and Prospects. Springer, New York, NY, 537pp.

Borah, D.K., G.S. Solanki & P.C. Bhattacharjee (2021). Feeding ecology of capped langur (Trachypithecus pileatus) in a disturbed habitat in Assam, India. Tropical Ecology 62(3): 492–498.

Burnham, K.P., D.R. Anderson & J.L. Laake (1980). Estimation of density from line transect sampling of biological populations. Wildlife Monographs (72): 3–202.

Campbell‐Smith, G., H.V. Simanjorang, N. Leader‐Williams & M. Linkie (2010). Local attitudes and perceptions toward crop‐raiding by orangutans (Pongo abelii) and other nonhuman primates in northern Sumatra, Indonesia. American Journal of Primatology 72(10): 866–876.

Cassano, C.R., J. Barlow & R. Pardini (2014). Forest loss or management intensification? Identifying causes of mammal decline in cacao agroforests. Biological Conservation 169: 14–22.

Champion, H.G. & S.K. Seth (1968). A Revised Survey of the Forest Types of India. Manager of publications, New Delhi, 404pp.

Chapman, C.A. & C.A. Peres (2001). Primate conservation in the new millennium: the role of scientists. Evolutionary Anthropology: Issues, News, and Reviews 10(1): 16–33.<16::aid-evan1010>;2-o

Chetry, D., R. Chetry, K. Ghosh & P.C. Bhattacharjee (2010). Status and conservation of golden langur in Chakrashila Wildlife Sanctuary, Assam, India. Primate Conservation 2010(25): 81–86.

Chetry, D., M. Phukan, R. Chetry, R.N. Boro, A.K. Das & P.C. Bhattacharjee (2020). Conservation Status of the Golden Langur Trachypithecus geei in Chakrashila Wildlife Sanctuary, Assam, India. Primate Conservation 2020(34): 167–173.

Choudhury, A.U. (2002). Golden langur Trachypithecus geei threatened by habitat fragmentation. Zoo’s Print Journal 17(2): 699–703.

Coleman, B.T. & R.A. Hill (2014). Living in a landscape of fear: the impact of predation, resource availability and habitat structure on primate range use. Animal Behaviour 88: 165–173.

Cowlishaw, G. (1999). Predicting the pattern of decline of African primate diversity: an extinction debt from historical deforestation. Conservation Biology 13(5): 1183–1193.

Cowlishaw, G. & R. Dunbar (2000). Primate Conservation Biology, University of Chicago Press, Chicago, 498pp.

Das, J., D. Chetry, R. Medhi & A. Choudhury (2020). Trachypithecus geei. The IUCN Red List of Threatened Species 2020: e.T22037A17960997. Downloaded on 06 March 2021. 3.RLTS.T22037A17960997.en

Davey, C.A., R.A. Pielke Sr. & K.P. Gallo (2006). Differences between near-surface equivalent temperature and temperature trends for the eastern United States: Equivalent temperature as an alternative measure of heat content. Global and Planetary Change 54(1–2): 19–32.

Doran, D. (1997). Influence of seasonality on activity patterns, feeding behavior, ranging, and grouping patterns in Tai chimpanzees. International Journal of Primatology 18(2): 183–206.

Dunning, J.B., B.J. Danielson & H.R. Pulliam (1992). Ecological processes that affect populations in complex landscapes. Oikos 65(1): 169–175.

Estrada, A., P.A. Garber, A.B. Rylands, C. Roos, E. Fernandez-Duque, A. Di Fiore, K.A.I Nekaris, V. Nijman, E.W. Heymann, J.E. Lambert & F. Rovero (2017). Impending extinction crisis of the world’s primates: Why primates matter. Science Advances 3(1): e1600946.

Fahrig, L. (2001). How much habitat is enough? Biological Conservation 100(1): 65–74.

Ferreira, A.S., Y. Le Pendu & R.A. Martinez (2018). The use of a mixed rubber landscape by tufted-ear marmosets. Primates 59(3): 293–300.

Foley, J.A., N. Ramankutty, K.A. Brauman, E.S. Cassidy, J.S. Gerber, M. Johnston, N.D. Mueller, C. O’Connell, D.K. Ray, P.C. West & C. Balzer (2011). Solutions for a cultivated planet. Nature 478(7369): 337–342.

Galán-Acedo, C., V. Arroyo-Rodríguez, A. Estrada & G. Ramos-Fernández (2019). Forest cover and matrix functionality drive the abundance and reproductive success of an endangered primate in two fragmented rainforests. Landscape Ecology 34(1): 147–158.

Ghosh, S. (2009). Report on the distribution and population status of golden langur (Trachypithecus geei) in Bodoland Territorial Council, Assam, India, 44pp.

Gibbs, H.K., A.S. Ruesch, F. Achard, M.K. Clayton, P. Holmgren, N. Ramankutty & J.A. Foley (2010). Tropical forests were the primary sources of new agricultural land in the 1980s and 1990s. Proceedings of the National Academy of Sciences 107(38): 16732–16737.

Isaac, N.J.B. & G. Cowlishaw (2004). How species respond to multiple extinction threats. Proceedings of the Royal Society of London, Series B: Biological Sciences, 271(1544): 1135–1141.

Khajuria, H. (1956). A new langur (Primates: Colobinae) from Goalpara district, Assam. Annals and Magazine of Natural History 12(9): 86–88.

Mammides, C., M. Cords & M.K. Peters (2009). Effects of habitat disturbance and food supply on population densities of three primate species in the Kakamega Forest, Kenya. African Journal of Ecology 47(1): 87–96.

Maxwell, S.L., R.A., Fuller, T.M. Brooks & J.E. Watson (2016). The ravages of guns, nets and bulldozers. Nature 536(7615): 143–145.

McKenney, B., Y. Chea, P. Tola & T. Evans (2004). Focusing on Cambodia’s high value forests: livelihoods and management. Cambodia Development Resource Institute; Wildlife Conservation Society, Phnom Penh, Cambodia, 129pp.

Medhi, R., D. Chetry, P.C. Bhattacharjee & B.N. Patiri (2004). Status of Trachypithecus geei in a rubber plantation in Western Assam, India. International Journal of Primatology 25(6): 1331–1337.

National Research Council (1981). Techniques for the study of primate population ecology. The National Academic Press, Washington DC, 255pp.

Oliveira, L.C. & J.M. Dietz (2011). Predation risk and the interspecific association of two Brazilian Atlantic forest primates in Cabruca agroforest. American Journal of Primatology 73: 852–860.

Pielke Sr., R.A., C. Davey & J. Morgan (2004). Assessing “global warming” with surface heat content. Eos, Transactions American Geophysical Union 85(21): 210–211.

Prevedello, J.A. & M.V. Vieira (2010). Does the type of matrix matter? A quantitative review of the evidence. Biodiversity and Conservation 19(5): 1205–1223.

Ram, M.S., S.M. Kittur, J. Biswas, S. Nag, J. Shil & G. Umapathy (2016). Genetic diversity and structure among isolated populations of the endangered gees golden langur in Assam, India. PLoS One 11(8): e0161866.

Rizaldi, K.I., I. Prasetio, Z.H. Lee, S. Jabbar & A. Ang (2019). Preliminary study on the distribution and conservation status of the east Sumatran banded langur Presbytis femoralis percura in Riau Province, Sumatra, Indonesia. Asian Primates Journal 8: 25–36.

Roy, D. & R. Nagarajan (2018). Biology, ecology, and conservation of golden langur, Trachypithecus geei. pp. 251–283. In: Sivaperuman, C., & K. Venkataraman (eds.). Indian hotspots: Vertebrate Faunal Diversity, Conservation and Management Volume 1. Springer, Singapore, 397pp.

Sakura, O. (1994). Factors affecting party size and composition of chimpanzees (Pan troglodytes verus) Bossou, Guinea. International Journal of Primatology 15(2): 167–183.

Shil, J., J. Biswas & H.N. Kumara (2020). Influence of habitat conditions on group size, social organization, and birth pattern of golden langur (Trachypithecus geei). Primates 61(6): 797–806.

Srivastava, A. (2006a). Conservation of threatened primates of Northeast India. Primate Conservation 2006(20): 107–113.

Srivastava, A. (2006b). Ecology and conservation of the golden langur, Trachypithecus geei, in Assam, India. Primate Conservation 2006(21): 163–170.

Srivastava, A., M. Baruah & S.M. Mohnot (2001a). The population dynamics and conservation of golden langur. Journal of the Bombay Natural History Society 98(1): 12–17.

Srivastava, A., J. Biswas, J. Das & P. Bujarbarua (2001b). Status and distribution of Golden Langurs (Trachypithecus geei) in Assam, India. American Journal of Primatology 55(1): 15–23.

Struhsaker, T.T. & J.F. Oates (1975). Comparison of the behavior and ecology of red colobus and black-and-white colobus monkeys in Uganda: a summary, pp. 103–123. In: Russel, H.T. (ed.). Socio-ecology and Psychology of Primates. Mouton Publishers, The Hague, Paris, 474pp.

Tordoff, A.W., R.J. Timmins, A. Maxwell, K. Huy, V. Lic & E.H. Khou (2005). Biological assessment of the Lower Mekong dry forests ecoregion final report. WWF, Phnom Penh, 192pp.

Umapathy, G., S. Hussain & S. Shivaji (2011). Impact of Habitat Fragmentation on the Demography of Lion-tailed Macaque (Macaca silenus) Populations in the Rainforests of Anamalai Hills, Western Ghats, India. International Journal of Primatology 32(4): 889–900.

Velankar, A.D., H.N. Kumara, A. Pal, P.S. Mishra & M. Singh (2016). Population Recovery of Nicobar Long-Tailed Macaque Macaca fascicularis umbrosus following a Tsunami in the Nicobar Islands, India. PLOS ONE 11(2): e0148205.

Wickham, J.D., T.G. Wade & K.H. Riitters (2012). Comparison of cropland and forest surface temperatures across the conterminous United States. Agricultural and Forest Meteorology 166-167: 137–143.

Wangchuk, T. (1997). A census and the biogeography of Golden Langurs (Presbytis geei) in Bhutan. Tigerpaper 22(3): 1–6.

Warren‐Thomas, E., P.M. Dolman & D.P. Edwards (2015). Increasing demand for natural rubber necessitates a robust sustainability initiative to mitigate impacts on tropical biodiversity. Conservation Letters 8(4): 230–241.

Watling, J.I., A.J. Nowakowski, M.A. Donnelly & J.L. Orrock (2011). Meta‐analysis reveals the importance of matrix composition for animals in fragmented habitat. Global Ecology and Biogeography 20(2): 209–217. Electronic version Accessed 12 March 2021.