Establishing baseline estimates of blue sheep (Pseudois nayaur) abundance and density to sustain populations of the vulnerable snow leopard (Panthera uncia) in Western Bhutan
Leki A , Phuntsho Thinley B C F , Rajanathan Rajaratnam D and Rinjan Shrestha E
+ Author Affiliations
- Author Affiliations
A Lingzhi Park Range, Jigme Dorji National Park, Department of Forests and Park Services, Gasa, Bhutan.
B Ugyen Wangchuck Institute for Conservation and Environment Research, Department of Forests and Park Services, Bumthang, Bhutan.
C Ecosystem Management, University of New England, Armidale, NSW 2350, Australia.
D Geography and Planning, University of New England, Armidale, NSW 2350, Australia.
E World Wildlife Fund, Toronto, ON M5V 1S8, Canada.
F Corresponding author. Email: chetsho78@gmail.com
Wildlife Research 45(1) 38-46 https://doi.org/10.1071/WR16218
Submitted: 26 March 2016 Accepted: 23 October 2017 Published: 29 March 2018
Abstract
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.
Additional keywords: double-observer survey, Eastern Himalayas, Jigme Dorji National Park, mountain ungulates, snow leopard conservation.
References
Anwar, M. B., Jackson, R., Nadeem, M. S., Janecka, J. E., Hussian, S., Beg, M. A., Muhammad, G., and Qayyum, M. (2011). Food habits of the snow leopard Panthera uncia (Schreber, 1775) in Baltistan, Northern Pakistan. European Journal of Wildlife Research 57, 1077–1083.| Food habits of the snow leopard Panthera uncia (Schreber, 1775) in Baltistan, Northern Pakistan.Crossref | GoogleScholarGoogle Scholar |
Aryal, A., Gastaur, S., Menzel, S., Chhetri, T. B., and Hopkins, J. B. (2010). Estimation of blue sheep population parameters in the Dhorpatan Hunting Reserve, Nepal. International Journal of Biodiversity and Conservation 2, 051–055.
Bagchi, S., and Mishra, C. (2006). Living with large carnivores: predation on livestock by the snow leopard (Uncia uncia). Journal of Zoology 268, 217–224.
| Living with large carnivores: predation on livestock by the snow leopard (Uncia uncia).Crossref | GoogleScholarGoogle Scholar |
Bhardwaj, M., Uniyal, V. P., Sanyal, A. K., and Sanyal, A. K. (2010). Estimating relative abundance and habitat use of Himalayan blue sheep Pseudois nayaur in Gangotri National Park, Western Himalaya, India. Galemys: Boletín informativo de la Sociedad Española para la conservación y estudio de los mamíferos 22, 545–560.
Burnham, K. P., Anderson, D. R., and Laake, J. L. (1980). Estimation of density from line transect sampling of biological populations. Wildlife Monographs 72, 3–202.
Cannon, P. F., Hywel-Jones, N. L., Maczey, N., Norbu, L., Samdup, T., and Lhendup, P. (2009). Steps towards sustainable harvest of Ophiocordyceps sinensis in Bhutan. Biodiversity and Conservation 18, 2263–2281.
| Steps towards sustainable harvest of Ophiocordyceps sinensis in Bhutan.Crossref | GoogleScholarGoogle Scholar |
Cao, L., Liu, Z., Wang, X., Hu, T., Zhai, H., and Hou, J. (2004). Winter group size and composition of blue sheep (Pseudois nayaur) in the Helan Mountains, China. Acta theriologica sinica 25, 200–204.
Devkota, B. P., Silwal, T., and Kolejka, J. (2013). Prey density and diet of snow leopard (Uncia Uncia) in Shey Phoksundo National Park, Nepal. Applied Ecology and Environmental Sciences 1, 55–60.
| Prey density and diet of snow leopard (Uncia Uncia) in Shey Phoksundo National Park, Nepal.Crossref | GoogleScholarGoogle Scholar |
DoL (Department of Livestock) (2006) ‘Livestock Statistics 2006.’ (Department of Livestock, Ministry of Agriculture and Forests: Thimphu, Bhutan.)
DoL (Department of Livestock) (2013) ‘Livestock Statistics 2013.’ (Department of Livestock, Ministry of Agriculture and Forests: Thimphu, Bhutan.)
Dzięciołowski, R. (1976). Estimating ungulate numbers in a forest by track counts. Acta Theriologica 21, 217–222.
| Estimating ungulate numbers in a forest by track counts.Crossref | GoogleScholarGoogle Scholar |
Eberhardt, L. (1978). Transect methods for population studies. The Journal of Wildlife Management 42, 1–31.
| Transect methods for population studies.Crossref | GoogleScholarGoogle Scholar |
Forsyth, D. M., and Hickling, G. J. (1997). An improved technique for indexing abundance of Himalayan thar. New Zealand Journal of Ecology 21, 97–101.
Fox, J. L., Sinha, S. P., Chundawat, R. S., and Das, P. K. (1991). Status of the snow leopard Panthera uncia in northwest India. Biological Conservation 55, 283–298.
| Status of the snow leopard Panthera uncia in northwest India.Crossref | GoogleScholarGoogle Scholar |
Harris, R. B. (2014). Pseudois nayaur. The IUCN Red List of Threatened Species 2014: e.T61513537A64313015.
Jackson, R. M. (1996) ‘Home Range, Movements and Habitat Use of Snow Leopard (Uncia uncia) in Nepal.’ (University of London: London.)
Jackson, R., and Hunter, D. O. (1996). ‘Snow Leopard Survey and Conservation Handbook.’ (International Snow Leopard Trust, Seattle, and U.S. Geological Survey, Biological Resources Division: Seattle, WA.)
Jackson, R. M., Roe, J. D., Wangchuk, R., and Hunter, D. O. (2006). Estimating snow leopard population abundance using photography and capture–recapture techniques. Wildlife Society Bulletin 34, 772–781.
| Estimating snow leopard population abundance using photography and capture–recapture techniques.Crossref | GoogleScholarGoogle Scholar |
Jiang, T., Wang, X., Ding, Y., Liu, Z., and Wang, Z. (2013). Behavioral responses of blue sheep (Pseudois nayaur) to nonlethal human recreational disturbance. Chinese Science Bulletin 58, 2237–2247.
| Behavioral responses of blue sheep (Pseudois nayaur) to nonlethal human recreational disturbance.Crossref | GoogleScholarGoogle Scholar |
Karanth, K. U., and Nichols, J. D. (1998). Estimation of tiger densities in India using photographic captures and recaptures. Ecology 79, 2852–2862.
| Estimation of tiger densities in India using photographic captures and recaptures.Crossref | GoogleScholarGoogle Scholar |
Karanth, K. U., and Stith, B. M. (1999). Prey depletion as a critical determinant of tiger population viability. In ‘Riding the Tiger: Tiger Conservation in Human Dominated Landscapes’. (Eds J. Seidensticker, S. Christie and P. Jackson.) pp. 100–113. (Cambridge University Press: Cambridge.)
Karanth, K. U., Chundawat, R. S., Nichol, J. D., and Kumar, N. S. (2004a). Estimation of tiger densities in the tropical dry forests of Panna, Central India, using photographic capture–recapture sampling. Animal Conservation 7, 285–290.
| Estimation of tiger densities in the tropical dry forests of Panna, Central India, using photographic capture–recapture sampling.Crossref | GoogleScholarGoogle Scholar |
Karanth, K. U., Nichols, J. D., Kumar, N. S., Link, W. A., and Hines, J. E. (2004b). Tigers and their prey: predicting carnivore densities from prey abundance. Proceedings of the National Academy of Sciences of the United States of America 101, 4854–4858.
| Tigers and their prey: predicting carnivore densities from prey abundance.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD2cXjsFCju70%3D&md5=d3bac2c35ec37a0aec44eb8b5ec329d5CAS |
Khan, M. M. H. (2012). Population and prey of the Bengal tiger Panthera tigris tigris (Linnaeus, 1758) (Carnivora: Felidae) in the Sundarbans, Bangladesh. Journal of Threatened Taxa 4, 2370–2380.
| Population and prey of the Bengal tiger Panthera tigris tigris (Linnaeus, 1758) (Carnivora: Felidae) in the Sundarbans, Bangladesh.Crossref | GoogleScholarGoogle Scholar |
Khatiwada, J. R., Chalise, M. K., and Kyes, R. C. (2007). Survey of snow leopard (Uncia uncia) and blue sheep (Pseudois nayaur) populations in the Kangchenjunga Conservation Area (KCA), Nepal. Snow Leopard Trust, Seattle, WA.
Laing, S., Buckland, S., Burn, R., Lambie, D., and Amphlett, A. (2003). Dung and nest surveys: estimating decay rates. Journal of Applied Ecology 40, 1102–1111.
| Dung and nest surveys: estimating decay rates.Crossref | GoogleScholarGoogle Scholar |
Lham, D., Thinley, P., Wangchuk, S., Wangchuk, N., Lham, K., Namgay, T., and Tharchen, L. Tenzin, and Phuntsho (2016). ‘National Snow Leopard Survey 2014–2016 (Phase II): Camera Trap Suvey for Population Estimation.’ p. 64. (Department of Forests and Parks Services, Ministry of Agriculture and Forests: Thimphu, Bhutan.)
Liu, Z., Wang, X., Li, Z., Cui, D., and Li, X. (2007). Feeding habitats of blue sheep (Pseudois nayaur) during winter and spring in Helan Mountains, China. Frontiers of Biology in China 2, 100–107.
| Feeding habitats of blue sheep (Pseudois nayaur) during winter and spring in Helan Mountains, China.Crossref | GoogleScholarGoogle Scholar |
Magnusson, W. E., Caughley, G. J., and Grigg, G. C. (1978). A double-survey estimate of population size from incomplete counts. The Journal of Wildlife Management 42, 174–176.
| A double-survey estimate of population size from incomplete counts.Crossref | GoogleScholarGoogle Scholar |
Mandujano, S., and Jones, C. A. (2005). Track count calibration to estimate density of white-tailed deer (Odocoileus virginianus) in Mexican dry tropical forest. The Southwestern Naturalist 50, 223–229.
| Track count calibration to estimate density of white-tailed deer (Odocoileus virginianus) in Mexican dry tropical forest.Crossref | GoogleScholarGoogle Scholar |
Marques, F. F., Buckland, S. T., Goffin, D., Dixon, C. E., Borchers, D. L., Mayle, B. A., and Peace, A. J. (2001). Estimating deer abundance from line transect surveys of dung: sika deer in southern Scotland. Journal of Applied Ecology 38, 349–363.
| Estimating deer abundance from line transect surveys of dung: sika deer in southern Scotland.Crossref | GoogleScholarGoogle Scholar |
McCarthy, T. M., and Chapron, G. (2003). ‘Snow Leopard Survival Strategy.’ (International Snow Leopard Trust and Snow Leopard Network: Seattle, WA.)
McCarthy, T., Mallon, D., Jackson, R., Zahler, P., and McCarthy, K. (2017). Panthera uncia. The IUCN Red List of Threatened Species 2017: e.T22732A50664030.
Mishra, C., Van Wieren, S. E., Ketner, P., Heitkönig, I., and Prins, H. H. (2004). Competition between domestic livestock and wild bharal Pseudois nayaur in the Indian Trans‐Himalaya. Journal of Applied Ecology 41, 344–354.
| Competition between domestic livestock and wild bharal Pseudois nayaur in the Indian Trans‐Himalaya.Crossref | GoogleScholarGoogle Scholar |
Nichols, J. D. (1992). Capture–recapture models. Bioscience 42, 94–102.
| Capture–recapture models.Crossref | GoogleScholarGoogle Scholar |
OCC (Office of the Census Commissioner) (2005). Population and Housing Census of Bhutan 2005. National Statistics Bureau, Thimphu, Bhutan.
Oli, M. K. (1994). Snow leopards and blue sheep in Nepal: densities and predator: prey ratio. Journal of Mammalogy 75, 998–1004.
| Snow leopards and blue sheep in Nepal: densities and predator: prey ratio.Crossref | GoogleScholarGoogle Scholar |
Oli, M., Taylor, I., and Rogers, D. M. (1993a). Diet of the snow leopard (Panthera uncia) in the Annapurna Conservation Area, Nepal. Journal of Zoology 231, 365–370.
| Diet of the snow leopard (Panthera uncia) in the Annapurna Conservation Area, Nepal.Crossref | GoogleScholarGoogle Scholar |
Oli, M. K., Taylor, I. R., and Rogers, M. E. (1993b). Diet of snow leopard (Panthera uncia) in the Annapurna Conservation Area, Nepal. Journal of Zoology 231, 365–370.
| Diet of snow leopard (Panthera uncia) in the Annapurna Conservation Area, Nepal.Crossref | GoogleScholarGoogle Scholar |
Royle, J. A., Chandler, R. B., Sollmann, R., and Gardner, B. (2013) ‘Spatial capture–recapture.’ (Academic Press: Waltham, MA.)
Schaller, G. B. (1973). On the behaviour of blue sheep (Pseudois nayaur). Journal of the Bombay Natural History Society 69, 523–537.
Schaller, G. B. (1977) ‘Mountain Monarchs: Wild Sheep and Goats of the Himalaya.’ (University of Chicago: Chicago, IL.)
Schaller, G. B., Junrang, R., and Mingjiang, Q. (1988). Status of the snow leopard Panthera uncia in Qinghai and Gansu provinces, China. Biological Conservation 45, 179–194.
| Status of the snow leopard Panthera uncia in Qinghai and Gansu provinces, China.Crossref | GoogleScholarGoogle Scholar |
Shehzad, W., McCarthy, T. M., Pompanon, F., Purevjav, L., Coissac, E., Riaz, T., and Taberlet, P. (2012). Prey preference of snow leopard (Panthera uncia) in south Gobi, Mongolia. PLoS One 7, e32104.
| Prey preference of snow leopard (Panthera uncia) in south Gobi, Mongolia.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BC38Xjs12lt7s%3D&md5=53b78126c843a8ab295e402f6950d394CAS |
Shrestha, R. (2007). ‘Coexistence of Wild and Domestic Ungulates in the Nepalese Trans-Himalaya: Resource Competition or Habitat Partitioning?’ (Norwegian University of Life Sciences: Aas, Norway.)
Shrestha, R., and Tenzin (2015). Population status and distribution of snow leopard (Panthera uncia) in Wangchuck Centennial National Park, Bhutan: a technical report. Wangchuck Centennial National Park, Thimphu, Bhutan.
Shrestha, R., and Wegge, P. (2008). Wild sheep and livestock in Nepal trans-Himalaya: coexistence or competition? Environmental Conservation 35, 125–136.
| Wild sheep and livestock in Nepal trans-Himalaya: coexistence or competition?Crossref | GoogleScholarGoogle Scholar |
Shrestha, R., Wangda, T., and Tashi, N. (2012). A report on population status and habitat utilization of naur (Pseudois nayaur) in Wangchuck Centennial Park, Bhutan. W. C. Park, Thimphu, Bhutan.
Simcharoen, S., Pattanavibool, A., Karanth, K. U., Nichols, J. D., and Kumar, N. S. (2007). How many tigers Panthera tigris are there in Huai Kha Khaeng Wildlife Sanctuary, Thailand? An estimate using photographic capture–recapture sampling. Oryx 41, 447–453.
| How many tigers Panthera tigris are there in Huai Kha Khaeng Wildlife Sanctuary, Thailand? An estimate using photographic capture–recapture sampling.Crossref | GoogleScholarGoogle Scholar |
Snow Leopard Working Secretariat (2013). ‘Global Snow Leopard Ecosystem Protection Program: a New International Effort to Save the Snow Leopard and Conserve High-Mountain Ecosystems.’ (Global Tiger Initiative Secretariat: Bishkek, Kyrgyz Republic.)
Suryawanshi, K. R., Bhatnagar, Y. V., and Mishra, C. (2012). Standardizing the double-observer survey method for estimating mountain ungulate prey of the endangered snow leopard. Oecologia 169, 581–590.
| Standardizing the double-observer survey method for estimating mountain ungulate prey of the endangered snow leopard.Crossref | GoogleScholarGoogle Scholar |
Thinley, P. (2013). First photographic evidence of a Pallas’s cat in Jigme Dorji National Park, Bhutan. CatNews 58, 27–28.
Thinley, P., Dagay, Leki, Dorji, P., Namgyel, C., Yoenten, S., Phuntsho, and Dorji, T. (2014). Estimating snow leopard (Panthera uncia) abundance and distribution in Jigme Dorji National Park using camera traps: a technical report. Jigme Dorji National Park, Thimphu, Bhutan.
Thinley, P., Dorji, S., Tempa, T., Wangchuk, N., Tandin, Namgyel, U., Tshewang, S., and Lham, D. (2015a). ‘Counting the Tigers in Bhutan: Report on the National Tiger Survey of Bhutan 2014–2015.’ (Department of Forests and Parks Services, Ministry of Agriculture and Forests: Thimphu, Bhutan.)
Thinley, P., Morreale, S. J., Curtis, P. D., Lassoie, J. P., Dorji, T., Leki, , Phuntsho, S., and Dorji, N. (2015b). Diversity, occupancy, and spatio-temporal occurrences of mammalian predators in Bhutan’s Jigme Dorji National Park. Bhutan Journal of Natural Resources and Development 2, 19–27.
Thinley, P., Tharchen, L., and Dorji, R. (2015c). Conservation management plan of Jigme Dorji National Park for the period January 2015–December 2019: biodiveristy conservation in pursuit of Gross National Happiness. Department of Forests and Park Services, Kuensel Corporation Ltd., Thimphu, Bhutan.
Wang, S. W., and Macdonald, D. W. (2009). The use of camera traps for estimating tiger and leopard populations in the high altitude mountains of Bhutan. Biological Conservation 142, 606–613.
| The use of camera traps for estimating tiger and leopard populations in the high altitude mountains of Bhutan.Crossref | GoogleScholarGoogle Scholar |
Wegge, P. (1979). Aspects of the population ecology of blue sheep in Nepal. Journal of Asian Ecology 1, 10–20.
Wegge, P., Shrestha, R., and Flagstad, O. (2012). Snow leopard Panthera uncia predation on livestock and wild prey in a mountain valley in northern Nepal: implications for conservation management. Wildlife Biology 18, 131–141.
| Snow leopard Panthera uncia predation on livestock and wild prey in a mountain valley in northern Nepal: implications for conservation management.Crossref | GoogleScholarGoogle Scholar |
Wikramanayake, E., Moktan, V., Aziz, T., Khaling, S., Khan, A. A., and Tshering, D. (2006). The WWF Snow Leopard Action Strategy for the Himalayan Region. (The World Wildlife Fund: Thimphu, Bhutan.)
Wilson, P. (1981). Ecology and habitat utilisation of blue sheep (Pseudois nayaur) in Nepal. Biological Conservation 21, 55–74.
| Ecology and habitat utilisation of blue sheep (Pseudois nayaur) in Nepal.Crossref | GoogleScholarGoogle Scholar |
Xu, A., Jiang, Z., Li, C., Guo, J., Da, S., Cui, Q., Yu, S., and Wu, G. (2008). Status and conservation of the snow leopard Panthera uncia in the Gouli Region, Kunlun Mountains, China. Oryx 42, 460–463.
| Status and conservation of the snow leopard Panthera uncia in the Gouli Region, Kunlun Mountains, China.Crossref | GoogleScholarGoogle Scholar |
Zhang, M., Wang, X., Ding, Y., Zhang, Z., Wang, Z., Li, Z., Hu, T., and Ma, B. (2012). Population dynamics of blue sheep Pseudois nayaur in Ningxia Helan Mountain National Nature Reserve, China. Folia Zoologica 61, 121–128.
| Population dynamics of blue sheep Pseudois nayaur in Ningxia Helan Mountain National Nature Reserve, China.Crossref | GoogleScholarGoogle Scholar |
