The coral reeves ecological resources of sea area of Dongsha are investigated and monitored (2)

Project Duration	2007-12-31 ~ 2008-12-30
Research Title	The coral reeves ecological resources of sea area of Dongsha are investigated and monitored (2)
Contracted Organization	Coral Reef Society of the Republic of China
Principal Investigator	Cheng Ming-Hsiu
Co-Principal Investigators	Dai Chang-Feng, Chen Cheng-Ping, Wang Wei-Long, Meng Pei-Chieh
Project Personnel	Lin Hsin-Yu, Chen Deng-Song, Tu Tzu-Hsuan, Chu Shu-Hui, Kuo Tao-Jen, Cheng An-Yi, Hung Sheng-Wen, Chen Jian-Xun, Cheng You-Rong, Ho Min-Chieh, Li Liang-Chan, Chen Pin-Chen, Chuang Yu
Keywords	Dongsha, Dongsha Atoll, coral reef, ecological resources
Abstract	1. Background: Dongsha officially became Taiwan’s seventh national park in 2007. Previously affected by fishing exploitation and the 1998 El Niño–induced global coral bleaching event, as well as more recent climate change impacts associated with global warming, the local environment has faced multiple pressures. During the five-year conservation period, protecting existing ecological resources is essential as a foundation for future tourism development. This project was commissioned to conduct biological and environmental surveys of Dongsha Atoll and to establish long-term monitoring methods to support park management. 2. Methods: The survey consisted of three main components: biological surveys, seawater quality analysis, and the selection and monitoring of indicator species. Biological surveys included corals, coral reef fishes, large benthic invertebrates, macroalgae, and seagrasses. Sixteen dive survey stations were completed in Dongsha waters, and seawater samples were collected around Dongsha Island for laboratory analysis. Based on past data, Dongsha Atoll was divided into three zones—outer atoll, lagoon, and waters surrounding Dongsha Island—for indicator species selection and feasibility evaluation. 3. Major Findings: 1. Indicator species were selected and long-term monitoring methodologies were established. 2. A total of 577 fish species were recorded, including 21 newly recorded species. 3. Coral surveys documented 229 species of scleractinian corals, 47 octocorals, and 5 hydrocorals, including 1 newly recorded genus and 19 newly recorded species. 4. Benthic invertebrates included 204 mollusk species, 30 echinoderm species, and 42 crustacean species, with 40 newly recorded species. 5. Seagrass and macroalgae surveys identified 41 species: 6 seagrasses, 7 green algae, 9 brown algae, 18 red algae, and 1 cyanobacterium species. 6. Water quality results indicate that Dongsha waters have not yet been affected by anthropogenic pollution. 7. Compared with previous surveys, coral recovery observed in 2006 after the mass bleaching event was not uniform in 2008. The western inner lagoon remains affected by environmental change, whereas the outer atoll and eastern areas are less susceptible to high-temperature impacts and maintain healthier coral reef conditions. 4. Recommendations: As a newly established national park, it is essential to implement and maintain long-term ecological monitoring systems to provide accurate management information and effectively support conservation policies.