Dongsha Atoll National Park has entered the coral spawning season. After continuous monitoring, the Marine National Park Headquarters (hereinafter referred to as MNPH) began recording floating coral spawn on the sea surface starting April 18. April 19 and 20 marked the peak spawning period following the spring tide, when large quantities of coral eggs and sperm were observed covering the sea surface. The 2014 coral spawning season is expected to continue through May.
MNPH indicated that although the average sea temperature in Dongsha in March remained below 25°C, stable and sustained high temperatures this spring caused water temperatures in April to exceed 25°C, accelerating the development of coral gonads. After microscopic examination confirmed the maturity of coral reproductive organs, MNPH staff observed small amounts of coral eggs floating in the water on April 18 (the 19th day of the third lunar month) following the spring tide. On the following night, branching Acropora species were observed spawning. On April 20, massive spawning events were recorded for species including Montipora, Porites, and digitate Acropora. The large quantities of coral gametes turned the sea into a “coral ocean,” and various marine organisms thrived in these nutrient-rich waters.
Because coral communities inside and outside the atoll differ in composition, and spawning conditions vary among species, it is difficult to determine the precise spawning time for each coral species. Predictions can only be made based on water temperature and microscopic examination of coral gonads. In recent years, surveys by MNPH have shown that Dongsha’s cold winter waters warm back to 25°C in March–April. Consequently, most recorded coral spawning events have occurred between April and May. However, specific spawning times may shift earlier in April or later into May depending on temperature variations. Long-term monitoring indicates that coral spawning in Dongsha typically lasts more than one month, with the next peak expected after the spring tide around the 15th day of the lunar month next month.
Located at the northern edge of the South China Sea, Dongsha Atoll resembles a precious oasis in the vast ocean, dispersing life throughout surrounding waters. The establishment of the national park preserves a sanctuary for its valuable coral reef ecosystems and aims to protect habitats so that life within the atoll may replenish the broader marine environment, sustaining the vitality of the ocean.

Figure 1. The clear waters of Dongsha Atoll allow direct views of the coral reefs beneath the surface.	Figure 2. A healthy coral reef ecosystem outside the atoll.
Figure 3. Branching Acropora spawning on the night of April 19.	Figure 4. Digitate Acropora spawning.
Figure 5. Montipora spawning.	Figure 6. Porites spawning.
Figure 7. After the spawning event, large amounts of coral eggs floated across the sea surface.	Figure 8. Coral eggs under a microscope, varying in size and color like colorful tapioca pearls.