On the morning of May 20, Zhang Yaxiong, a ranger at the Hainan Tropical Rainforest National Park Administration Jianfengling Branch Hainan Eld's Deer Conservation Station, stood beneath a tree, observing the grasslands along the edge of the Daguangba Reservoir through binoculars. There, he spotted six Hainan Eld's deer walking, grazing, and playfully leaping.

Hainan Eld’s Deer at the Hainan Datian National Nature Reserve.

The Hainan Eld’s Deer is a Class I protected wild animal species in China, and is found only on Hainan Island. This rare deer serves as a representative species within the global biodiversity conservation framework, and holds irreplaceable ecological value in maintaining the integrity and stability of Hainan Island's tropical ecosystem.

Previously, conservation of the Hainan Eld’s Deer was carried out primarily on site within the Hainan Datian National Nature Reserve and the Hainan Bangxi Provincial Nature Reserve. After decades of conservation work, the deer population gradually increased, but new challenges emerged. The two reserves have a combined total area of only around 20 square kilometers, with the core deer habitat zones are crowded closely together. Consequently, the Eld’s Deer population density exceeded the ecological carrying capacity of the reserves, leading to a scarcity of food resources and intense competition between within the population. Individual deer began to exhibit poor physical condition and compromised immunity. Fawn survival rates dropped while adult deer mortality rose, severely constraining the healthy and sustainable development of the population.

To help solve these problems, the Forestry Department of Hainan Province, along with the Hainan Tropical Rainforest National Park, launched a relocation project for the conservation of Hainan Eld’s Deer. In 2023, thirty deer were selected from the Hainan Bangxi Provincial Nature Reserve population and relocated to the Nanyao and Fengling Management Station areas, where conservation projects for the relocated deer were initiated. Thanks to dense forests filled with lush green vegetation, these areas provide ideal habitats for Hainan Eld’s Deer. Conservation staff conduct regular patrols and have also established emergency rescue protocols to assist the deer as they begin to adapt to their new home.

In July, 2025, Hainan Tropical Rainforest National Park Administration Bawangling Branch commissioned the Chinese Academy of Sciences Institute of Zoology to monitor the relocated Eld’s Deer population. The deer have been found to be in excellent physical condition, have fully adapted to the new environment, and have begun to reproduce naturally. By the end of 2025, the relocated population of Eld’s Deer had grown from the original 30 to a total of 47 deer, and the population is expected to continue to grow this year.

The successful conservation of the relocated Hainan Eld’s Deer offers a valuable reference case for the protection of rare and endangered wildlife. Moving forward, Hainan will continue to explore a variety of conservation models and refine the province’s biodiversity protection systems, giving even more rare local species the chance to thrive and multiply in the vibrant ecosystems of the island.