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Social structure and demography of a remnant Asian elephant Elephas maximus population and the implications for survival

  • Lauren J. Hale (a1), Kun Shi (a2), Tania C. Gilbert (a1), Kelvin S.-H. Peh (a1) and Philip Riordan (a3)...

Abstract

The Asian elephant Elephas maximus is at risk of extinction as a result of anthropogenic pressures, and remaining populations are often small and fragmented remnants, occupying a fraction of the species' former range. Once widely distributed across China, only a maximum of 245 elephants are estimated to survive across seven small populations. We assessed the Asian elephant population in Nangunhe National Nature Reserve in Lincang Prefecture, China, using camera traps during May–July 2017, to estimate the population size and structure of this genetically important population. Although detection probability was low (0.31), we estimated a total population size of c. 20 individuals, and an effective density of 0.39 elephants per km2. Social structure indicated a strong sex ratio bias towards females, with only one adult male detected within the population. Most of the elephants associated as one herd but three adult females remained separate from the herd throughout the trapping period. These results highlight the fragility of remnant elephant populations such as Nangunhe and we suggest options such as a managed metapopulation approach for their continued survival in China and more widely.

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Corresponding author

(Corresponding author) E-mail philipr@marwell.org.uk

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*

Also at: Marwell Wildlife, Winchester, UK

Also at: Wildlife Without Borders, Chelmsford, UK

Also at: Conservation Science Group, Department of Zoology, University of Cambridge, Cambridge, UK

§

Also at: School of Biological Sciences, University of Southampton, Southampton, UK

Supplementary material for this article is available at doi.org/10.1017/S0030605319000504

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References

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Social structure and demography of a remnant Asian elephant Elephas maximus population and the implications for survival

  • Lauren J. Hale (a1), Kun Shi (a2), Tania C. Gilbert (a1), Kelvin S.-H. Peh (a1) and Philip Riordan (a3)...

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