DOI: 10.5061/dryad.dv41ns247
title: Asian elephant microsatellite genotypes: Nakai Plateau and Sepon mines region, Lao PDR

description: Habitat loss and fragmentation are leading contributors to the endangered
 status of species. In 2006, the Nakai Plateau contained the largest known
 Asian elephant (Elephas maximus) population in the Lao People’s Democratic
 Republic (Lao PDR), and the population was among those with the highest
 genetic diversity reported for Asian elephants. In 2008, completion of the
 Nam Theun 2 hydroelectric dam inundated much of the Plateau, resulting in
 the loss of 40% of elephant habitat. We studied elephant presence,
 movements, and the incidence of human–elephant conflict (HEC) on the Nakai
 Plateau and surrounding areas from 2004-2020, before and for 12 years
 after dam completion. To examine contemporary population dynamics in the
 Nakai elephants, we used genetic sampling to compare minimum population
 numbers, demography, and levels of genetic diversity from the wet and dry
 seasons in 2018/2019, 10 years after dam completion, with those reported
 in a pre-dam-completion genetic survey. After dam completion, we found a
 major increase in HEC locally and the creation of new, serious, and
 persistent HEC problems as far as 100 km away. While we were unable to
 compare estimated population sizes before and after dam completion, our
 data revealed a decrease in genetic diversity, a male-biased sex ratio,
 and evidence of dispersal from the Plateau by breeding-age females. Our
 results raise concerns about the long-term viability of this important
 population as well as that of other species in this region. Given that
 hydropower projects are of economic importance throughout Laos and
 elsewhere in southeast Asia, this study has important implications for
 understanding and mitigating their impact.
description: From 2004 to 2020, teams from The Wildlife Conservation Society,
 The District Agriculture and Forestry Offices (DAFO) of affected districts
 in Lao PDR and the Nam Theun 2 Power Company (NTPC) conducted studies of
 the dynamics of elephant populations and the incidence of HEC on the Nakai
 Plateau and surrounding areas. They recorded the GPS location of each HEC
 incident, any available details about the elephants involved such as sex,
 age and group size, and the types of damage incurred.
 We analyzed the number and distribution of incidences of HEC in
 the periods before (2004-early 2009) and after dam completion.
 To characterize the elephant population on the Nakai Plateau 10
 years after dam completion, we collected fresh dung samples on the Nakai
 Plateau from 01 March 2018 – 01 May 2018 (dry season), and from 01 October
 2019 – 01 November 2019 (wet season). We genotyped
 those samples at 18 microsatellite loci and one sexing marker.
 We regenotyped 10 samples from our Nakai 2006 study (DOI:
 10.1007/s10592-010-0148-y) and 9 samples from our Sepon 2011 study (Eggert
 and Ruiz-Lopez 2012) at the 9 loci that all studies had in
 common. We compared levels of genetic diversity, sex
 ratio and age structure across the three studies.
 Literature cited: Eggert LS, Ruiz-Lopez M.
 2012. Analysis of fecal DNA samples to estimate the sex ratio and size of
 the Sepon Asian elephant population in the Lao PDR using capture-recapture
 methods. Report to the Wildlife Conservation Society.
description: None, these genotypes are provided in a Microsoft Excel file
 using GenePop 6 digit (2 alleles, 3 digits each) format.