Journal of Threatened Taxa | | 26 October 2019 | 11(13): 14757–14763



Mammal diversity in a montane forest in central Bhutan


Tashi Dhendup 1, Kinga Thinley 2  & Ugyen Tenzin 3


1,2,3 Ugyen Wangchuck Institute for Conservation and Environmental Research, Lamai Goempa, Bumthang 32001, Bhutan.

1 Wildlife Biology Program, Department of Ecosystem and Conservation Sciences, College of Forestry and Conservation, University of Montana, Missoula, MT, 59812, USA.

1 (corresponding author),2,3




doi:   |  ZooBank:


Editor: Anwaruddin Choudhury, Rhino Foundation for Nature in North-East India, Guwahati, India.         Date of publication: 26 October 2019 (online & print)


Manuscript details: #5058 | Received 18 June 2019 | Final received 17 October 2019 | Finally accepted 20 October 2019


Citation: Dhendup, T., K. Thinley & U. Tenzin (2019). Mammal diversity in a montane forest in central Bhutan. Journal of Threatened Taxa 11(13):14757–14763;


Copyright: © Dhendup et al 2019.  Creative Commons Attribution 4.0 International License.  JoTT allows unrestricted use, reproduction, and distribution of this article in any medium by adequate credit to the author(s) and the source of publication.


Funding: Ugyen Wangchuck Institute for Conservation and Environmental Research.


Competing interests: The authors declare no competing interests.


Acknowledgements: We are thankful to the management of the Ugyen Wangchuck Institute for Conservation and Environmental Research for funding and arranging the logistics for the study.  We also thank Dr. Tshering Tempa for his help during the initial planning stage of the current study.




Abstract In Bhutan, knowledge of wildlife species richness in protected areas is increasing, particularly for mammals; however, the knowledge outside of protected areas typically remains poor.  We conducted a camera trap survey from May 2016 to July 2017 in a montane forest outside of the protected areas network in central Bhutan and recorded 15 species of mammals (belonging to nine families and three orders), of which nearly half were listed as Endangered, Vulnerable, or Near Threatened.  Our findings demonstrate that forested landscapes outside protected areas in Bhutan support a rich assemblage of wildlife species and are, therefore, deserving of comprehensive wildlife conservation plans and dedicated funding for ecological research and threat mitigation.


Keywords: Biodiversity, camera trap, Himalaya, protected areas, threatened species.





Bhutan has close to 200 species of mammals (Wangchuk et al. 2004; NEC 2011) and is a part of the Himalaya Biodiversity Hotspot (Mittermeier et al. 2004) and the Global 200 ecoregions (Olsen & Dinerstein 2002).  Given the small geographical size of the country, the rich diversity of species can be attributed to its location at the junction of the Indo-malayan and the Palaearctic biogeographic realms.  Apart from the protected areas which comprise more than 50% of the country, other regions lack dedicated species inventories.  The lack of information deters comprehensive species conservation initiatives in the light of rapid changes to Bhutan’s rich and diverse ecosystem (Dhendup & Dorji 2018a; Penjor et al. 2018).  Camera traps have emerged as a successful and most frequently used tool for terrestrial species monitoring in Bhutan and have provided critical information on a few keystone and endangered species such as the Bengal Tiger (Wang & Macdonald 2009; Tempa et al. 2013; DoFPS 2015; Thinley et al. 2015) and Snow Leopard (DoFPS 2016; WCNP & WWF 2016).  Here we use camera traps to document the diversity and relative abundance of mammals in a montane forest in central Bhutan and also to provide baseline information to facilitate the preservation of such sites for the conservation of globally threatened species.


Materials and methods

We conducted the study in the Lamai Goempa Research Preserve in the Bumthang District of Bhutan (Figure 1).  The preserve spans an area of 1,098ha and is also used by local communities as grazing ground for cattle, extraction of timber, collection of non-wood forest products, and hiking.  The area receives an average annual rainfall of 1,404mm.  The summer temperatures can go up to 23°C, and the winter temperature can drop to -6°C (Pearl et al. 2015).  The vegetation comprises mixed conifer forest and alpine rhododendrons (Image 1 & 2).

We carried out the camera trapping survey from May 2016 to July 2017 using 25 camera stations established along footpaths, and game trails and the camera trapping array covered elevations from 2,892 to 4,120 m.  We placed one passive infra-red Reconyx HC500 Hyperfire camera (RECONYX, Inc., Wisconsin, USA) at each station and was set to operate for 24h (Image 3).  Cameras were at least 500m away from each other and were placed at the height of 45–50 cm above the ground.  No bait/lure was used.  For a series of images of the same species occurring at a camera trap location, we classified the captures as a notionally independent event only if they were taken at one-hour intervals (Sanderson & Harris 2013; Hodge & Arbogast 2016).  Memory cards from two camera stations were lost.  We calculated the relative abundance index (RAI), naïve occupancy, and the latency to initial detection for each species in the study area (Table 1).


Results and Discussion

The complete survey resulted in an effort of 4,501 trap nights and produced 34,237 photographs, of which 7,617 pictures were taken of 15 mammal species representing nine families and three orders (table 1) (Image 4–18).  The species detected were Tiger Panthera tigris, Asiatic Golden Cat  Catopuma temminckii, Marbled Cat Pardofelis marmorata, Leopard Cat Prionailurus bengalensis, Asiatic Wild Dog Cuon alpinus, Red Fox Vulpes vulpes, Himalayan Serow Capricornis thar, Barking Deer Mutiacus muntjac, Sambar Rusa unicolor, Wild Boar Sus scrofa, Yellow-throated Marten Martes flavigula, Asiatic Black Bear Ursus thibetanus, Himalayan Crestless Porcupine Hysterix brachyura, Orange-bellied Squirrel Dremomys lokriah, and Weasel Mustela sp.  Two are listed as Endangered, three Vulnerable, two Near Threatened, and the rest as Least Concern on the IUCN Red List of Threatened Species.  Although we did not record the Red Panda Ailurus fulgens, the River Otter Lutra lutra and other small mammals such as picas, rats and voles, these species are known to occur in the area and will require a species-specific survey protocol.  Wild Boars had the highest relative abundance index of 3.38 and also enjoyed the highest naïve occupancy among all the species.  Among the carnivores, the Asiatic Golden Cat and the Red Fox were the most common.  Tiger and weasel were the least common and were found in two camera stations each.  People were observed in 21 of the total 23 camera stations indicating a prominent level of human presence in the study site. 

The current study was one of the first systematic camera trapping for mammal inventory outside protected areas in Bhutan and has significant conservation implications for the country as most of the available information on fauna for management decisions come from protected areas.  The rich assemblage of mammals, including globally threatened species such as the Tiger and Wild Dog, suggests that the preserve is a primary habitat for many species and hence, requires protection and appropriate conservation interventions. The preserve is located near to two biodiversity-rich protected areas: Wangchuck Centennial National Park in the north and Phrumsengla National Park in the south.  Given the rich diversity of mammals in the area, putting up appropriate conservation strategies could provide additional biodiversity gains.  The area, however, is currently not fully gazetted as a research preserve and is under the jurisdiction of the Bumthang territorial division.  As such, the area is used for selective logging, grazing, and other resource allocations for communities living nearby.  Landscapes outside protected areas worldwide are facing an increase in human-induced land-use changes.  This may affect species both outside and within nearby protected areas.  The rich diversity of mammals in the area despite the strong human presence also demonstrates the possibility of human-wildlife coexistence (Moo et al. 2017).  Although the tiger and a few other species were detected only a few times, the region could be an important wildlife corridor and a part of their home range (Hodge & Arbogast 2016).  Therefore, we strongly feel the need to convert the area into a research preserve and be used for long term research, outreach, teaching, among others.

The National Tiger Survey of 2015 recorded more tigers outside protected areas (DoFPS 2015) and also documented the presence of six species of felids and five species of small carnivores in a forest division in western Bhutan (Dhendup & Dorji 2018a,b).  Unfortunately, these landscapes are highly vulnerable to habitat degradation and conversion and poaching.  Therefore, as home to many threatened and endangered species, lands outside protected areas also require comprehensive conservation management plans and critical funding to ensure that these landscapes continue to sustain biodiversity in the future.



Table 1. Details of mammal species recorded in Lamai Goempa Research Preserve, Bumthang, Bhutan during 2016–2017 with camera trap records, total capture events, relative abundance index (RAI), naïve occupancy and latency to initial detection.



Red List category1


Camera trap records

Total capture events

RAI/Trap success2

Naïve occupancy3

Latency to the initial detection3









Tiger Panthera tigris








Asiatic Golden Cat Catopuma temminckii








Marbled Cat Pardofelis marmorata








Leopard Cat Prionailurus bengalensis








Asiatic Wild Dog Cuon alpinus








Red Fox Vulpes vulpes








Yellow-throated Marten Martes flavigula








Asiatic Black Bear Ursus thibetanus








Weasel Mustela sp.
















Himalayan Serow Capricornis thar








Barking Deer Muntiacus muntjac








Sambar Rusa unicolor








Wild Boar Sus scrofa
















Himalayan Crestless Porcupine Hysterix brachyura








Orange-bellied Squirrel Dremomys lokriah








1 LC—Least Concern | NT—Near Threatened | VU—Vulnerable | EN—Endangered

2 Relative Abundance Index (RAI) was calculated as the number of captures divided by the total sampling effort in days multiplied by 100 (O’Brien 2011; Hedwig et al. 2018).

3 Naïve occupancy was quantified as the number of camera trap locations at which we detected each species divided by the total number of camera trap locations (Jenks et al. 2011; Rovero et al. 2014; Hedwig et al. 2018).

4 Latency to initial detection was determined as the number of trap nights between the start of the survey and the first record of a species (Gompper et al. 1999).



For figure  & images – click here




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