Abstract:

Background & Aims: Ex-situ conservation is an important part of the Convention on Biological Diversity, one of the objectives of the “Aichi Biodiversity Targets” and a strategic task and priority action of the China Biodiversity Conservation Strategy and Action Plan (2011‒2030). Milu (Père David’s deer) (Elaphurus davidianus) is listed as Class I National Key Protected Species of China. Before the wild population of Milu deer became extinct in China, captive populations were established overseas, which formed the basis for a reintroduction to China in 1985. Since reintroduction, the native population has become established and has expanded. The starting point for the reintroduction process was Beijing Milu Park, where 38 deer were reintroduced in 1985. After successful expansion of the population, the Beijing Milu Park began to send deer to other parts of the country. This article reviews the history and achievements of the reintroduction of Milu deer to China, examines the status of population development, and identifies challenges for the conservation of this species.
Results: Over the last 35 years, a total of 546 deer have been sent to other locations and, as at January 2021, Beijing Milu Park retains 183 deer in total. Dafeng Nature Reserve in Jiangsu Province is the second pillar of Milu deer’s reintroduction. After 39 deer were reintroduced to Dafeng in 1986, the population expanded to 78 in 1990, and to 5, 016 by the end of 2019, a 129-fold increase in the population since reintroduction. In 1995, Dafeng also began to send Milu deer to other sites across the country and, by the end of 2020, 164 had been sent to other locations. The distribution of Milu deer has expanded from just two sites in 1985‒1986 to 81 in 2020, covering all previous habitats before its extinction. Among these sites, six support wild populations, amounting to 2,855 individuals.
Perspectives & Suggestions: The restoration of the Milu deer population in China is a successful example of ex-situ conservation. However, the conservation of Milu deer faces challenges. There is no master plan for Milu deer conservation at the national level, so a coordinated monitoring platform and guidelines are lacking. Additionally, the Milu deer population lacks genetic diversity and is therefore vulnerable to multiple risks. The distribution of the wild population is limited and the number is small, thus hindering population stability. There is also a growing tension between population development and habitat carrying capacity, which hinders the sustainable growth of the population. In addition, the lack of an international cooperation mechanism hampers international collaboration and communication on Milu deer’s research. For all these reasons and others, the conservation of Milu deer is not secure. This article suggests strengthening ecological monitoring of the Milu deer population and developing a shared database and germplasm databank in order to improve genetic diversity. There is a need to expand the wild population in order to improve population stability, so as to secure the long-term conservation of this once extinct species.

Key words: China, Milu deer, ex-situ conservation, population development