Effects of a hydropower project on a high-value Asian elephant population.

Autor: Budd K; Division of Biological Sciences University of Missouri Columbia Missouri USA., Suddychan D; Nam Theun 2 Power Company Limited (NTPC) Vientiane Lao PDR., Tyson M; Biological Consultant Poolewe UK., Coudrat CNZ; Association Anoulak Nakai District Lao PDR., McWilliam A; International Union for Conservation of Nature (IUCN) Bangkok Thailand., Hallam CD; School of Bioscience University of Melbourne Melbourne Victoria Australia., Johnson A; Foundations of Success Bethesda Maryland USA.; Nelson Institute for Environmental Studies University of Wisconsin - Madison Madison Wisconsin USA., Eggert LS; Division of Biological Sciences University of Missouri Columbia Missouri USA.
Jazyk: angličtina
Zdroj: Ecology and evolution [Ecol Evol] 2023 Jul 25; Vol. 13 (7), pp. e10353. Date of Electronic Publication: 2023 Jul 25 (Print Publication: 2023).
DOI: 10.1002/ece3.10353
Abstrakt: 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 to 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.
Competing Interests: The authors declare that they have no conflicts of interest with respect to this work.
(© 2023 The Authors. Ecology and Evolution published by John Wiley & Sons Ltd.)
Databáze: MEDLINE
Externí odkaz: