In the absence of systematic research institutions and local or long-term resident systematists added by Buddhist culture that discourages lethal sampling of animals, scientific collections are particularly sparse in Bhutan. Consequently, less charismatic taxa such as the reptile and amphibian fauna of Bhutan, including the Eastern-Himalayas, are poorly known. Citizen science was employed to better understand the occupancy and distribution of reptile and amphibian fauna in Bhutan. Using a dedicated amphibian and reptile Facebook group, we gathered 929 species records from 235 individuals between May 2014 and December 2019. Of the participants 70% were foresters, 10% were members of the general public, 6% were school teachers, 6% were college students, 5% were non-forester civil servants, and 3% were tour guides. Citizen scientists submitted records for 99 species of snakes, 70 species of amphibians, 87 species of lizards and 5 species of testudines. Of these, 70% of the records extended the published range of the species in Bhutan, and more than 48 species were new records for Bhutan. Our study demonstrates the potential of citizen science in developing countries with poorly documented fauna.

Mammal diversity in Biological Corridor No. 03 covering the Sarpang–Tsirang District landscapes of Bhutan

Photographic evidence of the Spotted linsang Prionodon pardicolor (Mammalia: Carnivora: Prionodontidae) from the Tashigang Forest Division, Eastern Bhutan

Birds are ecological indicators of ecosystem health. Baseline information on bird diversity are, therefore, important for ecological monitoring. Such information is, however, sorely lacking for many areas outside the protected areas. Here, we explore the avian diversity and present a comprehensive checklist for the non-protected regions of Trashiyangtse District in northeastern Bhutan. We also categorise the bird species by their residency pattern, feeding guilds, abundance, and IUCN Red List status. We conducted an avifauna exploration for a period of four years from 2017 to 2020, mostly through opportunistic encounters coinciding with regular field visits. We recorded a total of 273 bird species belonging to 173 genera, 69 families and 19 orders. Passeriformes was the most dominant order with 41 families and 174 species and Muscicapidae was the most dominant family with 12 genera and 32 species. Most birds were altitudinal migrants (39%), insectivorous (45%), and occasional (44%) in terms of residency pattern, feeding guild, and abundance, respectively. Only one species (Ardea insignis) was listed as Critically Endangered and one (Haliaeetus leucoryphus) as Endangered. Our study identified the non-protected regions of Trashiyangtse District as an important bird diversity area in Bhutan.

The snow leopard ( Panthera uncia ) is one of the world's most elusive felids. In Bhutan, which is one of the 12 countries where the species still persists, reliable information on its distribution and habitat suitability is lacking, thus impeding effective conservation planning for the species. To fill this knowledge gap, we created a country-wide species distribution model using “presence-only” data from 420 snow leopard occurrences (345 from a sign survey and 77 from a camera-trapping survey) and 12 environmental covariates consisting of biophysical and anthropogenic factors. We analyzed the data in an ensemble model framework which combines the outputs from several species distribution models. To assess the adequacy of Bhutan's network of protected areas and their potential contribution toward the conservation of the species, we overlaid the output of the ensemble model on the spatial layers of protected areas and biological corridors. The ensemble model identified 7,206 km 2 of Bhutan as suitable for the snow leopard: 3,647 km 2 as highly suitable, 2,681 km 2 as moderately suitable, and 878 km 2 as marginally suitable. Forty percent of the total suitable habitat consisted of protected areas and a further 8% of biological corridors. These suitable habitats were characterized by a mean livestock density of 1.3 individuals per hectare, and a mean slope of 25°; they closely match the distribution of the snow leopard's main wild prey, the bharal ( Pseudois nayaur ). Our study shows that Bhutan's northern protected areas are a centre for snow leopard conservation both at the national and regional scale.

Most canids face population declines and range contractions worldwide. Although the dhole ( Cuon alpinus ) is widely distributed across 10 countries in South and Southeast Asia, limited studies exist on this species. Despite its globally “Endangered” status and ecological role as an apex predator, assessments on its distribution are limited to a few landscapes and countries. This explains the lack of a dhole-specific species conservation plan in most range countries, including Bhutan where no current population estimate exists. The species has also recovered from a country-wide poisoning campaign in the 1970s and 80s. In this study, we determine the dhole's distribution pattern and assess the protection and connectivity of dhole habitat in Bhutan. We anticipated dholes to be extant within their habitat well-represented in protected areas (PAs) and biological corridors (BCs). We used 721 georeferenced dhole occurrence records and eight environmental variables in MaxEnt software to model potential dhole distribution and habitat suitability. The model output was overlaid on the spatial layers of PAs and BCs to assess habitat protection and connectivity. As anticipated, we found the dhole widely distributed in all districts, PAs, and BCs in Bhutan. Dholes were recorded at the highest elevation range limit of 4,980 m above sea level, which overlapped with the “Vulnerable” snow leopard ( Panthera uncia ). Our model identified 72% (27,634 km 2 ) of the country as suitable areas for dholes, of which, 31% (11,899 km 2 ) was highly suitable and 41% (15,735 km 2 ) was moderately suitable. Contrary to our expectation, PAs and BCs encompassed only 29% (8,046 km 2 ) and 12% (3,185 km 2 ) of suitable areas for dholes, respectively. A vast majority of the areas we deemed suitable for dholes currently remain unprotected, thus making dholes more vulnerable to human persecution and local extermination. We recommend adjusting PA boundaries to fully encompass suitable dhole habitat, and also advocate improved livestock husbandry to reduce dhole related livestock predation and minimize conflict, thereby ensuring its long-term survival in Bhutan.

Bhutan has a total geographical area of 38,394 Km² located in between the Indo-Malayan and Palearctic region, out of which 51.44% (19750.75 km²) of its total geographical area has been designated as the protected area. However, none of the districts have a structured baseline checklist of mammal species documented till date. Therefore, Sarpang Forest Division under the Department of Forests and Park Services had carried out five rigorous camera trap surveys including a nationwide tiger survey that covers representable areas of the district from 2014 till 2020. The survey shows that district has 36 mammal species that belong to 18 families under seven orders. Felidae and Cervidae families has the highest species abundance (n = 17%), while, Canidae, Herpestidae, Leporidae, Manidae, Melinae, Muridae, Mustelidae, Tupaiidae, Proboscidae, Pteromyidae, Suidae and Ursidae were the lowest (n = 3%). Above all, Sarpang homed 29.90% of total mammal species of Bhutan, out of which 3% of mammal species were categorized under Critically Endangered, 14% Endangered, 14% Vulnerable, 22% Near Threatened, and 47% Least Concern as per IUCN Red List. However, only 20 mammal species are listed under CITES and nine in Schedule I of Forest and Nature Conservation Act of Bhutan, 1995. Therefore, landscape-based planning such as the Division-based Conservation & Management plan; periodic monitoring of wildlife species using camera traps, and validation of Schedule I species are suggested for long-term conservation and management of globally threatened species inside the landscape of Sarpang district in Bhutan.

Understanding human–canid conflict and coexistence must focus on documenting human–canid interactions and identifying the underlying drivers of reciprocal human attitude which enables appropriate strategies to minimize conflict and forge coexistence. The dhole ( Cuon alpinus ), Asia's most widely distributed wild canid, is highly threatened by human persecution and anthropogenic activities. Despite its “endangered” status, its ecological role as an apex predator, negative interactions with humans, and dhole-specific attitude studies are limited, thus hindering the development of a comprehensive dhole-conservation strategy. Here, we investigate the influence of socioeconomic factors of age, gender, income, residency inside/outside a protected area (PA), and other variables (cultural beliefs, livestock loss, and quantity of livestock loss) on the attitudes of local people and support for dhole conservation in the Himalayan Kingdom of Bhutan. We conducted a semi-structured questionnaire survey of 1,444 households located within the PA and non-PA from four representative regions in the country. Using R programming, we ran Pearson's chi-square test of independence to test the overall difference in the attitude and support for dhole conservation, followed by recursive partitioning through a conditional inference regression tree to identify its significant covariates with the highest explanatory power. Majority (79.1%) of respondents (χ 2 = 488.6; df = 1; p < 0.001) disliked the dhole over those who liked it. More than half (57.7%) (χ 2 = 412.7; df = 2; p < 0.001) opposed dhole conservation over those who either supported or remained neutral. Experience of livestock loss to dholes was the primary ( p < 0.001) factor influencing the negative attitude and opposition to dhole conservation, despite an acknowledgment of the ecological role of the dhole in controlling agricultural crop predators. Our study, which is the first-ever survey in Bhutan, solely focused on investigating human attitudes and perceptions toward the dhole, indicating that livestock loss to dholes transcends all positive attitudes to the species and drives a predominant dislike and opposition to its conservation. To improve the attitude and support toward the dhole and to foster dhole–human coexistence, livestock predation by dholes needs alleviation by improving the existing animal husbandry, in conjunction with promoting conservation awareness on this species.

Abstract Protected area networks (PAN) are essential for conserving wide‐ranging apex predators but their adequacy in species protection has rarely been assessed. Here, we assess the adequacy of Bhutan's PAN in conserving and providing connectivity to the endangered tiger (Panthera tigris). We determine the current extent of tiger habitat, predict new suitable habitat, identify potential corridors, and empirically estimate the range of tiger numbers that Bhutan can spatially support. We use two spatial models with different approaches to ascertain current tiger distribution and predict new suitable tiger areas: (a) an expert model based on tiger ecology and (b) an observation model from observed tiger distribution. The expert model identified more suitable tiger areas (32,887 km2) over the observation model (29,962 km2), with the PAN encompassing 46% and 45% of predicted suitable areas, respectively. Vast suitable tiger habitat remains unprotected. Based on our estimates of total suitable habitats, Bhutan can spatially support 138–151 tigers compared to the current estimate of 103, thereby precluding a doubling in tiger numbers. To ensure adequate protection of tigers in Bhutan, we recommend readjusting and/or expanding existing PAN boundaries, including the designation of new corridors, protecting habitats, and conserving prey populations.

Small mammals have multiple ecological roles and are important components of the terrestrial ecosystems. They are important ecological indicators of changes in the natural surroundings. However, little is known about the small mammals in Bhutan. We conducted this study in the Bumdeling Ramsar Site in eastern region of Bhutan, aimed at enhancing our understanding of the species composition, abundance, and seasonal diversity of small mammals. We laid linear transects, each measuring 500 m in six different habitat types: agriculture land (AG), fallow land (FL), Alnus sp. forest (AF), open grassland (OG), riparian forest (RR), and oak forest (OF). We placed 17 collapsible Sherman live traps (23x9x8cm) in each transect to capture both ground dwelling and arboreal small mammals. We conducted the trapping exercise twice in the year 2016 (28 March to 28 April during the wet season and 1 to 30 October during the dry season), amounting to a total of 1,224 trap nights. We trapped a total of 135 individuals of small mammals, yielding seven species of rodents (90 individuals; 66.7%) and four of insectivores (45 individuals; 33.3%). We found significant difference in the number of individuals trapped among the six different habitats (X2=66.43, df= 5, P<0.05) with the highest in AG (59 individuals, 43.7%) and the lowest in OG (1 individual; 0.7%) during the dry and wet season, respectively. In order to promote diversity of small mammals in the Ramsar site, we recommend reducing free-range cattle grazing and restraining domestic dogs in the vicinity of the Ramsar site. *Corresponding Author: Lam Norbu  lam.norbu@ymail.com Journal of Biodiversity and Environmental Sciences (JBES) ISSN: 2220-6663 (Print) 2222-3045 (Online) Vol. 15, No. 3, p. 36-45, 2020 http://www.innspub.net J. Bio. & Env. Sci. 2019 37 | Norbu et al. Introduction Small mammals (rodent, shrew and lagamorph ≤ 500g or 1kg) form a majority of the mammalian fauna, and they are an important component of most natural and semi-natural ecosystems (Ofori et al., 2015). They perform ecological roles in dispersal of seeds (Aplin et al., 2003; Garshong et al., 2013) and fungal spores (Gupta, 2011), nutrient cycling (Sieg, 1987; Klerk, 2014), and decomposition and mediation of energy flow through consumption and shedding of vegetation (Hoffmann et al., 2010). They also often dubbded as environmental engineers because of their role in soil aeration through digging and burrowing, and in extreme cases, altering the whole landscape (Garshong et al., 2013; Gyeltshen, 2015). They also serve as essential prey for many mammals, birds and reptiles (Garshong et al., 2013; Chane and Yirga, 2014). They are, thus, known to play an important role in determining forest structure, composition and succession of vegetation (Ofori et al., 2015). Their abundance and composition in turn, are influenced by habitat structure, productivity and other important environmental factors (Demeke and Afework, 2014; Tuyisingize et al., 2014; Assefa and Srinivasulu, 2019). Small mammals are considered to be good bioindicators of habitats because of their short lifespan, rapid population dynamics, and low level of hunting pressure in comparison to larger mammals (Karuaera, 2011, Chane and Yirga, 2014). Most small mammals are prolific breeders; hence, they represent significant amount of the animal biomass in forest and other natural ecosystem (Aplin et al., 2003). They are also the major agricultural pests, causing substiantial damage to crops and stored farm produce (Karuaera, 2011; Ofori et al., 2015). Further, they also serve as parasitic host and disease reserviors (Avenant and Cavallini, 2008; Bantihun, 2012). On a gobal scale, there are approximately 5,416 species of mammals (Bantihun and Bekele, 2015) of which 2,706 (50%) are small mammals (Wolff and Sherman, 2007; Molur and Singh, 2009; Datiko and Bekele, 2013). South Asia alone has recorded 185 species of small mammals of which 62 are endemic to the region (Molur et al., 2005). Among the South Asian countries, India has 120 species of small mammals representing 66% of Indian mammal records (Walker, 2003; Gyeltshen, 2015). Similarly, Nepal has 158 species of small mammals representing more than 60% of mammal records, and one species being endemic to Nepal (Katuwal and Koirala, 2012). In Bhutan, there is very few documentations of small mammals, and hence, little is known about them with respect to their species diversity, distribution, conservation status, and ecology. This is largely attributed to limited explorations and studies conducted so far in the country. In fact, documentation of small mammals was initiated only in 1993, following which a few studies were conducted in the recent years. Wangmo et al., (2014) listed four species of small mammal from Royal Manas National Park (RMNP) in south-central region of Bhutan. Gyeltshen (2015) conducted an exploration in Jigme Dorji Nation Park (JDNP) in western Bhutan where he recorded six species of rodents. In the same year, Dorji (2015) added seven species of high-altitude rodents and shrews in the wetlands of Phobjikha, which is the third Ramsar Site in Bhutan. All of these studies are concentrated in the western region of the country, and there is no exploration from the eastern region. Therefore, we conducted this study in the eastern region of Bhutan, aimed at enhancing our understanding of the species composition, abundance, and seasonal diversity of small mammals. Materials and methods Study area We conducted the study in the Bumdeling Ramsar Site (27°39’33.86” N, 91°25’47.73” E), which is situated inside the Bumdeling Wildlife Sanctuary (BWS; Fig.1), in north-eastern part of Bhutan. Our study site was designated as a Ramsar Site in 2012 in recognition of the conservation significance of the charismatic and ‘Vulnerable’ black-necked crane (Grus nigricollis) which winters annually in the area. On an average, about 90 individuals of this bird arrive J. Bio. & Env. Sci. 2019 38 | Norbu et al. and reside in the area every year. It covers an area of 1.42 km2. The elevation of the adjacent forest ranges from 1,900 to 2,050 m above sea level (a.s.l.). The wetland has 160 species of plants, 73 of birds, 38 of snakes, seven of lizards, seven of fishes and 12 of mammals (UNESCO, 2012). Among the large predators, the globally threatened and flagship species such as the Bengal tiger (Panthera tigris) is known to coexist with Himalayan black bear (Ursus thibetanus), dhole (Cuon alpinus), and red panda (Ailurus fulgens). Bhutan’s national butterfly (Bhutanitis ludlowi) is also recorded in the study area (UNESCO, 2012; Poel, 2013). The mean annual temperature recorded is 20.20C and the mean annual rainfall is 1,065 mm (UNESCO, 2012). People residing in the vicinity of the study site follow subsistence farming which consists of crop cultivation, livestock rearing, and sale of non-timber forest produce. They also collect firewood, house construction timber, and NWFPs (such as bamboo, barks of daphne (Daphne bholua), fiddle heads, mushrooms, and many other wild vegetables) from the nearby forests. We selected six habitat types based on the dominant species composition: agriculture land (AG), fallow land (FL), Alnus forest (AF), open grassland (OG), riparian forest (RR), and oak forest (OF). Fig. 1. Map showing study location in Bumdeling Ramsar Site (Trashiyangtse, Bhutan). Live trapping of small mammals At the outset, we conducted a preliminary survey in order to be able to appropriately select the trapping sites. Relevant site information such as topography, climatic conditions, and the associated flora and fauna were gathered. We conducted the trapping exercise twice in the year 2016 to compare seasonal diversity of small mammals: first round from 28 March to 28 April during the wet season and the second from 1 to 30 October during the dry season. This amounted to a total of 1,224 trap nights. Transect lengths varying from 400 to 500 meters have been used in small mammal surveys (Klerk, 2014; Dorji, 2016). We laid linear transects, each measuring 500 m in six different habitat types of the study area. We placed a total of 17 collapsible Sherman live traps (23x9x8cm) in each transect, spaced by an interval distance of 15 m to capture both ground dwelling and arboreal small mammals. We kept the traps for three consecutive days to capture all possible small mammals. As recommended by Cunningham and Moors (1996) and Hoffmann et al., (2010), we placed the traps in areas with high likelihood of small mammal visitation, such as proximity to rocks, caves, burrows, log side, bushes, fences, sheds, tree buttresses, coarse woody debris, visible droppings, food remains and runway. The traps were covered with litters, foliage and hays to camouflage and provide insulation (Barnett and Dutton, 1995; Pearson and Ruggiero, 2003). This also prevented the local people, cow herders, and stray dogs from being attracted by the shiny surfaces of the traps. We baited each trap with locally made flour dough mixed with ground nuts, apples, grapes, bananas, wheat biscuits, dry salty fish, bread, canned fish and fresh carrot following the baiting method of Barnett and Dutton (1995). In order to be able to relocate the traps, we marked each trap location with red cloth tagged on a stick or a branch of a nearby tree or shrub. We inspected each trap twice a day: once in early morning from 7:00 hrs to 9:00 hrs and once in the late afternoon from 17:30 hrs to 19 hrs. This was to capture both diurnal and nocturnal animals (Bantihun and Bekele, 2015). During each inspection visit, we checked the baits and replenished them wherever necessary to increase trapping success and to avoid loss of animal lives J. Bio. & Env. Sci. 2019 39 | Norbu et al. from hunger. We cautiously removed each trapped animal, placed in a polythene bag, and weighted using Pesola ® spring balance of 200g capacity. Next, we measured each animal using the standard morphol

The tiger Panthera tigris is globally ‘Endangered’ (Goodrich et al., 2015). The Himalayan Kingdom of Bhutan is an important stronghold (Tempa et al., 2019) for this ecologically and economically important apex predator (Estes et al., 2011; Thinley et al., 2018). Here, we report the reappearance of the tiger in Bumdeling Wildlife Sanctuary (BWS) in north-eastern Bhutan (Fig. 1a), after a likely absence of 12 years. Bumdeling Wildlife Sanctuary is bordered by China in the north and India in the east, and covers 1520 km across the districts of Trashiyangtse, Mongar and Lhuentse (Fig. 1a). Altitudes range from 1500 to 6450 m above sea level and the sanctuary contains 745, 42 and 334 species of plants, mammals and birds, respectively (BWS, 2013). Other large predators present in the sanctuary include the snow leopard P. uncia, common leopard P. pardus and dhole Cuon alpinus. They subsist on a diverse ungulate community comprising sambar Rusa unicolor, muntjac Muntiacus muntjac, blue sheep Pseudois nayaur, musk deer Moschus chrysogaster, serow Capricornis thar and goral Naemorhedus goral. There are approximately 800 people who are resident in BWS, predominantly living as subsistence agro-pastoralists (BWS, 2013). Evidence of tiger presence in BWS was initially based on an anecdotal sighting at Thiling village in Sherimuhung Geog in 2001 (subdistrict; Fig. 1b); a claim of 12 yaks predated by tiger between 2003 and 2004 at Rongmateng village in Khoma Geog (Fig. 1b); and sanctuary personnel documenting tiger pugmarks in 2004 at Dongla within Yangtse Geog (Fig. 1b). However, camera trapping in BWS after 2004, including a comprehensive National Tiger Survey (NTS) from 2014 to 2015, failed to capture any tiger images (Thinley et al., 2015). This absence of sightings puzzled local tiger biologists, given the historic presence of tigers in the area, adequate prey availability, minimal hunting and no tiger poaching. Dissatisfied by the poor camera trapping results, sanctuary staff intensified field surveys in 2016 and a tiger pugmark

Forest fire is an environmental disaster that poses immense threat to public safety, infrastructure, and biodiversity. Therefore, it is essential to have a rapid and robust method to produce reliable forest fire maps, especially in a data-poor country or region. In this study, the knowledge-based qualitative Analytic Hierarchy Process (AHP) and the statistical-based quantitative Frequency Ratio (FR) techniques were utilized to model forest fire-prone areas in the Himalayan Kingdom of Bhutan. Seven forest fire conditioning factors were used: land-use land cover, distance from human settlement, distance from road, distance from international border, aspect, elevation, and slope. The fire-prone maps generated by both models were validated using the Area Under Curve assessment method. The FR-based model yielded a fire-prone map with higher accuracy (87% success rate; 82% prediction rate) than the AHP-based model (71% success rate; 63% prediction rate). However, both the models showed almost similar extent of ‘very high’ prone areas in Bhutan, which corresponded to coniferous-dominated areas, lower elevations, steeper slopes, and areas close to human settlements, roads, and the southern international border. Moderate Resolution Imaging Spectroradiometer (MODIS) fire points were overlaid on the model generated maps to assess their reliability in predicting forest fires. They were found to be not reliable in Bhutan, as most of them overlapped with fire-prone classes, such as ‘moderate’, ‘low’, and ‘very low’. The fire-prone map derived from the FR model will assist Bhutan’s Department of Forests and Park Services to update its current National Forest Fire Management Strategy.

Despite the golden langur's (Trachypithecus geei) endangered and totally protected status, local awareness and attitude toward this species is poorly understood. We investigated local awareness and attitude in Bhutan by interviewing 1,143 households in the districts of Dagana, Sarpang, Trongsa, Tsirang, and Zhemgang, and analyzing data through a conditional inference tree analysis. Most respondents were not aware of the golden langur's nationally protected (53%; n = 604) and globally endangered status (64%; n = 730), but their location of residence (inside/outside a protected area; p < .001) and education level (p < .001) significantly influenced awareness. The majority of respondents (87%; n = 999) liked the golden langur but the attitude was significantly influenced primarily by whether or not they experienced crop damage by golden langurs (p < .001), and subsequently by location of residence (p < .001), local belief (p < .01), gender (p < .05), and personal encounter with a golden langur (p < .001). Socioeconomic variables like age, education level, and annual income did not influence attitude. We recommend environmental education and awareness campaigns outside protected areas, and intensifying existing programs inside protected areas to forge harmonious human-golden langur coexistence.

Threat assessment is critical to species conservation and management planning, because prior identification and assessment of key threats to conservation planning can assist in developing appropriate interventions or strategies. Comprehensive threat assessments are currently lacking for many threatened primates. In this paper, we classify and rank all direct threats to the endangered golden langur (Trachypithecus geei) in Bhutan in order to provide a practical guide to future conservation of the species. Information on threats was based on interviews with local people, discussion with field forestry staff, and social media interaction. We classified threats to golden langur habitats and populations, and ranked them using Miradi™, an analytical software for the adaptive management of conservation projects. We identified five habitat threats: (1) hydropower development, (2) road development, (3) housing development, (4) resource extraction, and (5) agricultural expansion. We also identified seven population threats: (1) electrocution, (2) road kill, (3) road injury, (4) dog kill, (5) retaliatory killing, (6) illegal pet keeping, and (7) hybridization with capped langurs. We rated the overall threat to golden langurs in Bhutan as 'medium'. Hydropower, road, and housing development constituted 'high' impact, while agricultural expansion, resource extraction, electrocution, and road kill had 'medium' impact; the remaining threats had 'low' impact. To immediately mitigate threats to golden langurs, we recommend: (a) installing speed limit signage and speed breakers with strict enforcement of speed limits; (b) installing insulated electric cables and fencing around power transformers; and (c) reducing and restraining domestic dog populations.

Reliable population estimates are lacking for many South Asian primate species, including the golden langur (Trachypithecus geei), which is endangered and restricted to Bhutan and northeast India. Although well studied in India, few studies exist on this species in Bhutan. In November 2017, we undertook a nationwide survey of golden langurs in Bhutan using double observers along trail-based transects in 17 blocks within its habitat, and modeled its distribution using MaxEnt. A total of 2439 golden langurs in 222 groups were collectively encountered by 17 teams of double observers, from which, an overall population of 2516 ± SE 363 individuals and 236 ± SE 9 groups were estimated. Group sizes varied from 2 to 35 individuals with a mean of 11 ± SD 0.38 individuals. A total of 468 adult males (19%), 924 adult females (38%), 649 juveniles (27%), and 398 infants (16%) were counted. Adult male-to-female sex ratio was 1:1.97 and adult female-to-infant ratio was 1:0.43. We determined 2848 km2 of suitable area for golden langurs in Bhutan and estimated a density of 0.88 individuals/km2. Our population estimate of golden langurs in Bhutan is much lower than the current IUCN estimate of 4000 individuals for Bhutan, necessitating a reassessment of its current conservation status due to threats from road kills, electrocution, and development activities like road construction, hydropower, and electrical transmission lines. We further recommend our refined double-observer survey method to reliably estimate primate populations in rugged terrain.

Ecologists have primarily focused their attention on how predator loss influences ecosystem structure and function in intact ecosystems, but rarely tested these ecological concepts in agricultural landscapes. We conducted a study in western Bhutan on the inter-specific dynamics between tigers, leopards, and dholes, and their subsequent impact on livestock and crop losses faced by agro-pastoralists. We found that when a tiger was present in forests surrounding villages, leopards and dholes occupied areas closer to village croplands and preyed on a higher relative abundance of wild herbivore crop raiders, thereby significantly reducing crop (beta = -2.25, p < .0001) and livestock losses (beta = -2.39, p <= .0001). In contrast, leopards and dholes occupied areas in deep forests farther from croplands when a tiger was absent in the village vicinity, leading to increased predation on a higher abundance of untended free-ranging livestock. We posit that justifications for large predator conservation based on their iconic status is not persuasive to rural farmers residing close to their habitat and suffering crop and livestock loss. There is a need to determine ecological services from apex predators to farmers which may dissuade them from retaliatory killings. We recommend conservation practitioners conserve large apex predators to maintain optimal inter-specific interactions in a large predator guild to benefit rural socio-economy.

Context Advances have been made in the development of reliable methods for estimating the abundance and density of large threatened mammalian predators, but there is little progress on developing population estimates for their principal prey. No standardised protocol for estimating prey populations exists, therefore different researchers use different methods. As such, there is little information on key prey species of the vulnerable snow leopard and this has hindered the preparation of effective snow leopard conservation plans. Aims This study aimed to establish an estimated seasonal baseline population abundance and density of blue sheep in the Lingzhi Park Range (LPR) of Bhutan’s Jigme Dorji National Park over winter (December to February) and summer (May to July). It also aimed to assess the number of snow leopard individuals that the current blue sheep population can sustain in the study area. Methods A refined double-observer survey method was used and involved walking transect lengths of 414 km in winter and 450 km in summer to estimate blue sheep abundance with the aid of 8 × 30 binoculars and 15 × 45 spotting scopes. Key results In total, 1762 (s.e. ± 199) blue sheep individuals were recorded in winter at a density of 8.51 individuals per km2 and 2097 (s.e. ± 172) individuals in summer at a density of 9.32 individuals per km2. Mean group size of blue sheep was 38.12 individuals (s.e. ± 6) in winter and 52.36 individuals (s.e. ± 4) in summer. LPR was estimated to sustain 11–17 snow leopards in winter and 15–21 in summer. Key conclusions LPR can be a hotspot for snow leopard conservation in western Bhutan and regionally in the eastern Himalayas, because the comparatively higher estimated blue sheep abundance and density supports possibly the highest density of snow leopards in Bhutan. The modified double-observer method used to assess blue sheep population estimates is inexpensive, robust and practical for the mountainous terrain of the Himalayas. Implications On the basis of this study, it is recommended that a refined double-observer method is adopted as a standard technique for estimating blue sheep populations in the snow leopard range countries of the Himalayas. Snow leopard conservation plans should, additionally, include efforts to minimise threats to blue sheep populations. This refined method is also highly applicable for future surveys of gregarious mammalian taxa, such as ungulates and primates, in difficult mountainous terrain elsewhere in the world.

As in many developing countries, agro-pastoralism is the major form of livelihood for rural communities in the Himalayan Kingdom of Bhutan. Although livestock rearing is part and parcel of rural Bhutanese agricultural system, Bhutan also has a high percentage of natural forest cover that supports a diversity of endangered wild predators. The loss of cattle to these predators is an on-going source of conflict between predators, farmers, and wildlife managers. Despite awareness of predation losses, there has been no empirical assessment of livestock herding practices in Bhutan in terms of livestock vulnerability to predation. We conducted a questionnaire and a field survey in three districts of western Bhutan to assess current livestock herding practices with regard to predation vulnerability. We interviewed farmers using a semi-structured questionnaire to determine their livestock herding practices and losses. We also traversed human trails in the nearby forests and took note of livestock encountered to gain further insights into herding dynamics. Generally, livestock were more vulnerable to predation when released into the forests without accompanying herders. Seasonally, livestock were more vulnerable during summer and early autumn, which coincided with the peak farming period during which animals are typically released into forests with minimal care. Our study underscores the importance of livestock herding with accompanying herders to minimize predation losses and highlights the challenges posed by farm labour shortage in rural areas. We recommend developing a comprehensive livestock management policy that includes elaborate provisions on reducing livestock losses through livestock herd management, stock improvement, fodder development, pasture development, and sustainable livestock insurance schemes.