Imagine a triangle. The top angle to the north is Luzon Island in the Philippines. Thence, downward to the west, the Berau waters of East Kalimantan stretch out. At the opposite point to the east, North Sulawesi completes the triangle. Marine conservationists call the triangle “the heart of the world’s coral reefs.”

In the triangle, known as the Sulu-Sulawesi Seascape, there exist almost all sorts of the world’s coral reefs. The water i