Habitat suitability of Proboscis monkey (Nasalis larvatus) in Berau Delta, East Kalimantan, Indonesia




The proboscis monkey (Nasalis larvatus) is an endemic species to Borneos’ island and is largely confined to mangrove, riverine, and swamp forest. Most of their habitat is outside the conservation due to degraded and habitat converted. Habitat loss is a significant threat to a decreased in the monkey's population. Berau Delta is an unprotected habitat of proboscis monkey, lacking in attention and experiencing a lot of disturbances. This study was conducted on April – August 2019; with aims of the study is to determine Species Distribution Modeling (SDM) for identifying proboscis monkey habitat suitability in Delta Berau, East Kalimantan. The MaxEnt algorithm was used to produce a habitat suitability map based on this species’ occurrence records and environmental predictors. We built the models using 208 points of proboscis monkey presence and 12 environment variables within the study area. Model performance was assessed by examining the area under the curve. The variables most influencing the habitat suitability model were the riverine habitat (60.9%), distance from the pond (16.0%), and distance from the coastline (5.2%). The proboscis monkey suitable habitat is only 9.32% (8,726.58 ha) from 93,631.41 ha total area. The appropriate habitat areas are Sapinang Island, Bungkung Island, Sambuayan Island, Saodang Kecil Island, Besing Island, Lati River, Bebanir Lama, Batu-Batu, and Semanting Bay. We provide some suggestions for the proboscis monkey conservation, which are local protection of uninhabited islands, participatory ecotourism management, and company involvement in protection and management efforts.


Ajayi SR, Ogunjobi JA. 2016. Composition of large mammals day-time visitation to salt lick sites inside Kainji Lake National Park, Nigeria. Ife J Sci 17(2):335–340.
Akinwande MO, Dikko HG, Samson A. 2015. Variance Inflation Factor: As a condition for the inclusion of suppressor variable (s) in regression analysis. Open J Stat 5:754–767.
Atmoko T. 2015. The habitat and distribution of proboscis monkey in Mahakam Delta, East Kalimantan. In: Alikodra HS, Bismark M, Sondjoto MA (eds.). The Struggle Against Extinction. Bogor: IPB Press. pp. 119–140. [Indonesian]
Atmoko T. 2016. State of the art and conservation effort of proboscis monkey (Nasalis larvatus) in Kalimantan. In: Proceeding of Balitek KSDA Research Results Seminary. Balitek KSDA, Balikpapan. [Indonesian]
Atmoko T, Ma’ruf A, Rinaldi SE, Sitepu BS. 2012. The distribution of proboscis monkey (Nasalis larvatus Wurmb.) in Balikpapan Bay, East Kalimantan. In: Proceedings of Balitek KSDA Research Results Seminary. Balitek KSDA, Balikpapan. [Indonesian]
Bismark M. 2009. Conservation Biology of Proboscis monkey (Nasalis larvatus). Bogor: Puslitbang Hutan dan Konservasi Alam. [Indonesian]
Blake JG, Mosquera D, Guerra J, Loiselle BA, Romo D, Swing K. 2011. Mineral licks as diversity hotspots in lowland forest of Eastern Ecuador. Diversity 3(2):217–234.
Boonratana R. 2000. Ranging behavior of proboscis monkeys (Nasalis larvatus) in the Lower Kinabatangan, Northern Borneo. Int J Primatol 21(3):497-518.
Boonratana R. 2013. Fragmentation and its significance on the conservation of proboscis monkey (Nasalis larvatus) in the Lower Kinabatangan, Sabah (North Borneo). In: L.K. Marsh & C.A. Chapman (eds.). Primates in Fragments: Complexity and Resilience, Developments in Primatology: Progress and Prospects. New York: Springer. pp. 459–475.
Boonratana R, Cheyne SM, Traeholt C, Nijman V, Supriatna J. 2020. Nasalis larvatus. IUCN Red List Threat. Species 2020. [access 2020 Agu 10]. Tersedia pada: https://dx.doi.org/10.2305/IUCN.UK.2020-2.RLTS.T14352A17945165.en.
Booth TH. 2018. Why understanding the pioneering and continuing contributions of BIOCLIM to species distribution modelling is important. Austral Ecol 43(8):852–860.
Budke JC, Jarenkow JA, Oliveira-Filho AT de. 2008. Tree community features of two stands of riverine forest under different flooding regimes in Southern Brazil. Flora 203:162–174.
Chetan N, Praveen KK, Vasudeva GK. 2014. Delineating ecological boundaries of hanuman langur species complex in Peninsular India using MaxEnt modeling approach. PLoS One 9(2):1–11.
Counotte G, Holzhauer M, Carp-van Dijken S, Muskens J, Van der Merwe D. 2019. Levels of trace elements and potential toxic elements in bovine livers: A trend analysis from 2007 to 2018. PLoS One 14(4):1–11.
Dewi EK, Trisakti B. 2016. Comparing atmospheric correction methods for landsat OLI data. Int J Remote Sens Earth Sci 13(2):105–120.
Dong X. 2019. Suitable habitat prediction of sichuan snub-nosed monkeys (Rhinopithecus roxellana) and its implications for conservation in Baihe Nature Reserve, Sichuan, China. Environ Sci Pollut Res 26:32374–32384.
Filho RF, Palmeirim JM. 2019. Potential distribution of and priority conservation areas for the endangered caatinga howler monkey Alouatta ululata in North-Eastern Brazil. Oryx. doi:10.1017/S0030605318001084.
Fitzgerald M, Coulson R, Lawing AM, Matsuzawa T, Koops K. 2018. Modeling habitat suitability for chimpanzees (Pan troglodytes verus) in the Greater Nimba Landscape, Guinea, West Africa. Primates 59(4):361–375.
Franklin J, Jennifer JM. 2009. Mapping Species Distributions spacial inference and prediction. Cambridge, UK: Cambridge University Press.
Guisan A, Thomas C. Edwards J, Hastie T. 2002. Generalized linear and generalized additive models in studies of species distributions: Setting the scene. Ecol Modell 157:89-100.
Hasnawi, Indra A, Asaad J, Mustafa A. 2015. Characteristics of existing pond land in Derawan Island District, Berau Regency, East Kalimantan Province. J. Ris. Akuakultur. 10(4):593–608. [Indonesian]
Katovai E, Katovai DD, Edwards W, Laurance WF. 2015. Forest structure, plant diversity and local endemism in a highly varied New Guinea landscape. Trop Conserv Sci 8(2):284–300.
Loi DT, Chou T, Fang Y. 2017. Integration of GIS and remote sensing for evaluating Forest Canopy Density Index in Thai Nguyen Province, Vietnam. Int J Environ Sci Dev 8(8):539–542.
Loi N Van. 2008. Use of GIS Modelling in Assessment of Forestry Land’s Potential in Thu Thien Hue Province of Central Vietnam. Dissertation. Georg-August-Universität zu Göttingen.
Maingi JK, Marsh SE. 2006. Composition, structure, and regeneration patterns in a gallery forest along the Tana River near Bura, Kenya. For Ecol Manage 236:211–228.
Manansang J, Traylor-Holzer K, Reed D, Leus K. 2005. Indonesian Proboscis Monkey PHVA Indonesian. IUCN/SSC Conserv. Breed. Spec. Gr.(December):76.
Matsuda I, Abram NK, Stark DJ, Sha JCM, Ancrenaz M, Goossens B, Lackman I, Tuuga A, Kubo T. 2018. Population dynamics of the proboscis monkey Nasalis larvatus in the Lower Kinabatangan, Sabah, Borneo, Malaysia. Oryx. doi:10.1017/S0030605318000467.
Meijaard E, Nijman V. 2000. Distribution and conservation of the proboscis monkey (Nasalis larvatus) in Kalimantan, Indonesia Biol Conserv 92(1):15-24.
Merow C, Smith MJ, Silander JA. 2013. A practical guide to MaxEnt for modeling species’ distributions?: what it does, and why inputs and settings matter. Ecography 36:1058–1069.
Peterson AT, Soberon J, Pearson RG, Anderson RP, Martinez-Meyer E, Nakamura M, Araujo MB. 2011. Ecological Niches and Geographic Distributions. Princeton and Oxford: Princeton University Press.
Phillips Q, Phillips K. 2016. Field Guide to The Mammals of Borneo and Their Ecology. England: John Beaufoy Publishing Ltd.
Phillips S., Anderson R., Schapire R. 2006. Maximum entropy modeling of species geographic distributions. Ecol Model 190:231–259.
Prasetyo LB. 2017. Landscape Ecology Approach for Biodiversity Conservation. Bogor: Faculty of Forestry, IPB University. [Indonesian]
Rahman DA, Rinaldi D, Kuswanda W, Siregar R, Ch FN, Hakim F, Arief H, Putro HR. 2019. Determining the landscape priority and their threats for the critically endangered Pongo tapanuliensis population in Indonesia. Biodiversitas 20(12):3584–3592.
Rikimaru A, Roy PS, Miyatake S. 2002. Tropical forest cover density mapping. Trop Ecol 43(1):39–47.
Sarquis JA, Cristaldi MA, Arzamendia V, Bellini G, Giraudo AR. 2018. Species distribution models and empirical test: Comparing predictions with well-understood geographical distribution of Bothrops alternatus in Argentina. Ecol Evol 8(21):10497–10509.
Soendjoto MA, Nazaruddin. 2012. Distribution of the proboscis monkey (Nasalis larvatus) in Balangan District, South Kalimantan, Indonesia. Tigerpaper 39(2):1–7.
Suttle NF. 2010. Mineral Nutrition of Livestock, 4th Edition. 4th Editio. Wallingford, UK: CABI Publishing.
Suwarto, Prasetyo LB, Kartono AP. 2016. Suitability habitat of proboscis monkey (Nasalis larvatus Wurmb, 1781) in mangrove forest Kutai National Park, East Kalimantan. Bonorowo Wetl 6(1):12–25. [Indonesian]
Thinley P, Norbu T, Rajaratnam R, Vernes K, Wangchuk K, Choki K, Tenzin J, Tenzin S, Kinley, Dorji S, Wangchuk T, Cheda K, Gempa. 2019. Population abundance and distribution of the endangered golden langur (Trachypithecus geei) in Bhutan. Primates 60(5):437–448.
Thorne JH, Seo C, Basabose A, Gray M, Belfiore NM, Hijmans RJ. 2013. Alternative biological assumptions strongly influence models of climate change effects on mountain gorillas. Ecosphere 4(9):1–17.
Tuan Anh N, Duc Minh L, Viet Hung P, Thi Duyen V. 2019. Modeling the red-shanked douc (Pygathrix nemaeus) distribution in Vietnam using Maxent. VNU J Sci Earth Environ Sci 35(3):61–71.
Uniyal S, Ashwin K, Mishra A, Sahoo JK, Paladan V. 2018. Importance of micro minerals in reproductive performance of farm animals. Int J Curr Microbiol Appl Sci 7(7):3584–3589.
Wardatutthoyyibah, Pudyatmoko S, Subrata SA, Imron MA. 2019. The sufficiency of existed protected areas in conserving the habitat of proboscis monkey (Nasalis larvatus). Biodiversitas 20(1):1–10.
Widyastuti S, Perwitasari-Farajallah D, Prasetyo LB, Iskandar E, Setiawan A. 2020. Maxent modelling of habitat suitability for the endangered javan gibbon (Hylobates moloch) in less-protected Dieng Mountains, Central Java. IOP Conf Ser Earth Environ Sci 457.doi:10.1088/1755-1315/457/1/012014.
Yan H, Feng L, Zhao Y, Feng L, Wu D. 2020. Prediction of the spatial distribution of Alternanthera philoxeroides in China based on ArcGIS and MaxEnt. Glob. Ecol. Conserv. 21.doi:10.1016/j.gecco.2019.e00856.
Yoshihara Y, Mizuno H, Ogura S, Sasaki T, Sato S. 2013. Increasing the number of plant species in a pasture improves the mineral balance of grazing beef cattle. Anim Feed Sci Technol 179(1–4):138–143.

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