Conservation Genetics

, Volume 15, Issue 4, pp 803–810 | Cite as

Population size estimation of an Asian elephant population in eastern Cambodia through non-invasive mark-recapture sampling

  • Thomas N. E. Gray
  • T. N. C. Vidya
  • Sheetal Potdar
  • D. K. Bharti
  • Prum Sovanna
Research Article


The Asian elephant is a flagship species for conservation in tropical Asia, but reliable population estimates are available only from a few populations. This is because the species can be elusive and occurs at low densities in dense habitat over a large part of its range. Phnom Prich Wildlife Sanctuary in the Eastern Plains, Cambodia, which is part of one of the largest protected area complexes in South-East Asia, is one such habitat that had not been systematically censused for elephants. We, therefore, used fecal-DNA based capture-mark-recapture sampling to estimate the population size for establishing a monitoring baseline. Five sampling sessions targeted all areas in and adjacent to Phnom Prich Wildlife Sanctuary believed to be used by elephants. Fresh dung was collected as the source of DNA and genotyping was carried out based on nine microsatellite loci. The 224 samples collected yielded 78 unique genotypes. Using model averaging of closed population capture-mark-recapture models, the elephant population in Phnom Prich Wildlife Sanctuary was estimated to number 136 ± 18 (SE) individuals. Our results suggest that eastern Cambodia supports a regionally important Asian elephant population.


Genetic mark-recapture Population estimation Noninvasive sampling Cambodia Phnom Prich Wildlife Sanctuary 



This study forms part of WWF Greater Mekong Cambodia Country Program’s Eastern Plains Landscape Project. Work in PPWS was carried out with permission of the Department for Wildlife and Nature Conservation of the Cambodian Ministry of the Environment, and support from His Excellency Chay Samith. Permits for exporting elephant fecal-DNA samples from Cambodia were obtained from the Ministry of Agriculture, Forestry and Fisheries of the Royal Cambodian Government. Permits for importing samples were obtained from the National Biodiversity Authority, Ministry of Environment and Forests, Government of India, and Additional Principal Chief Conservator of Forests (Wildlife), Karnataka State Forest Department. Sary Tre, Dong Kit, Sem Pros, Yet Sreng, Ngoeum Nareoun, Gkill, Kham Mephoeung, and Mel Trock assisted with data collection, whilst Christy Williams, Andrew Maxwell, Phan Channa, Craig Bruce, Barney Long, and Seng Teak provided support. Anitha CA, Nandini Shetty, and Kanika Mendiratta assisted with some laboratory analysis. We thank two anonymous reviewers for comments that helped improve the manuscript.

Supplementary material

10592_2014_579_MOESM1_ESM.docx (22 kb)
Supplementary material 1 (DOCX 21 kb)


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Copyright information

© Springer Science+Business Media Dordrecht 2014

Authors and Affiliations

  1. 1.World Wide Fund for Nature (WWF) Cambodia Country ProgramEastern Plains Landscape ProjectSen MonoromCambodia
  2. 2.WWF Greater MekongVientianeLao PDR
  3. 3.Evolutionary and Organismal Biology UnitJawaharlal Nehru Centre for Advanced Scientific Research (JNCASR)BangaloreIndia
  4. 4.Centre for Ecological SciencesIndian Institute of ScienceBangaloreIndia
  5. 5.Forestry Administration, Ministry of Agriculture, Forestry and FisheriesRoyal Government of CambodiaPhnom PenhCambodia

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