A Retrospective Analysis on the Population Viability of the Yangtze River Dolphin or Baiji (Lipotes vexillifer)

DOI: 10.18805/ijar.B-1238    | Article Id: B-1238 | Page : 775-779
Citation :- A Retrospective Analysis on the Population Viability of the Yangtze River Dolphin or Baiji (Lipotes vexillifer).Indian Journal of Animal Research.2022.(56):775-779
Wu Bin, Wang Weiping, Wang Haihua, He Gang wubinjx@163.com
Address : Fisheries Research Institute of Jiangxi Province, Scientific Observing and Experimental Station of Fishery Resources and Environment in Poyang Lake, Ministry of Agriculture, 330000 Nanchang, China.
Submitted Date : 1-01-2020
Accepted Date : 24-04-2020


Background: Lipotes vexillifer,  is a functionally extinct species of freshwater dolphin commonly called as Baiji dolphin of Yanzte River, China. The dolphin is thought to be the first one of it’s kind driven to extinction due to the impact of humans. Yangtze Freshwater Dolphin Expedition carried out in the year 2006 revealed the species as functionally extinct. The présent study deals with the population viability analysis of the baiji dolphin using Vortex software and also by consulting historical materials and relevant literature to explore the possible causes of the functional extinction of the baiji in the Yangtze River. The findings are to provide guidance for the effective management of another freshwater mammal, the Yangtze finless porpoise.
Methods: Population viability analysis of the baiji dolphin for various parameters were assessed using Vortex software and other published information and relevant literatures. The analysis were carried out to ascertain the possible causes of the functional extinction of the baiji in the Yangtze River.
Result: Simulation models were employed to identify the reasons for extinction of Yangtze River baiji population by adopting viability retrospective method. The various parameters associated with the population analysis were included to derive logical conclusion. The minimum viable population of the Yangtze River baiji was also identified by adopting various simulation models. The present study is the first attempt to apply the 10,000-time iteration method to the baiji population survivability analysis.


Lipotes vexillifer PVA Vortex model MVP Habitat


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