Abstract: Nypa fruticans Wurmb. is a true mangrove species in family Arecaceae. As a key protected species in China, it is only distributed in Hainan Island. N. fruticans is a relict species with important scientific value in tropical flora, paleontology, marine geoarchaeology, and paleobotany. To understand the endangered status and protection strategy of N. fruticans, we investigated resource status, community characteristics, population structure, and distribution pattern of N. fruticans. The results showed that: (1) There were six natural populations of N. fruticans, with 9319 individuals covering a total area of 3.96 hm², which distributed in Wild Pineapple Island and Daoxue Village in Dongzhai Port of Haikou, Yuyang Park and Touyuan Village in Wenchang City, Wenchang Village in Qionghai, and Riyue Bay in Wanning. (2) There were 28 mangrove species in the community, and the dominant species were N. fruticans+Bruguiera sexangula+Parmentiera cerifera, and N. fruticans+B. sexangula. (3) The populations in Haikou, Qionghai, and Wanning were declining, while that in Wenchang was increasing. All populations exhibited clumped distributions. (4) Extreme climate change, excessive deforestation and exploitation, and limited reproduction of individuals were the three main reasons leading to the endangered N. fruticans populations. We call for scientific research and technology input to solve the problem of provenance, strengthen habitat restoration and in situ conservation, and optimize ex situ conservation and field return strategies to expand the population.

Key words: relict plant, Nypa fruticans, endangered status, conservation strategy, population structure.