Johnson South Reef Johnson South Reef Johnson South Reef (; ), also known as Chigua Reef in China, Gạc Ma Reef in Vietnam and Mabini Reef in the Philippines is a reef in the southwest portion of the Union Banks in the Spratly Islands of the South China Sea. It is controlled by the People's Republic of China (PRC), but its ownership is disputed by the PRC, the Philippines, Taiwan, and Vietnam. Johnson South Reef lies adjacent to the Vietnamese-controlled Collins Reef (also known as Johnson North Reef) which lies to the northwest. It is naturally above water only at low tide. Prior
Apo Reef facilities are available onshore to protect the island's fragile ecosystem. Apo Menor is located near the western end of Apo Reef, about east of Apo Island. It is a rocky limestone island with relatively little vegetation. Cayos del Bajo are flat coralline rock formations with no vegetation on the northern lagoon near the eastern edge of the reef. At low tide, many small rocks are dry on the reef, particularly along its north side. The main activity of the reef relates to its underwater quality. Scuba diving and snorkeling in Apo Reef area are exceptional due to the quality of