Ocean Environment
¡@The east coast of Taiwan is formed of stone while the west coast is mud and sand; so most of the island's coral is concentrated around the northern and southern tips, with lesser amounts found scattered along the east coast and around the smaller offshore islands.
¡@Since the Tropic of Cancer cuts the island in half, Taiwan is divided into both subtropical and tropical areas with different seasonal temperature changes and varying water temperatures. In the north, the average water temperature undergoes seasonal changes from 19.8 degrees to 25 degrees Celsius (at Patoutzu); in the south, the average varies from 23 degrees to 28 degrees Celsius (at Maopitou). The result is two very different types of underwater scenery: subtropical in the north, tropical in the south. Coral and fish varieties also exhibit appreciable differences according to geographic location. Some species of fish, for example, are seen frequently in the north but never in the south. By the same token, hundreds of varieties of reef fish that favor warm-water habitats are seen only in the south, but never around the coral reefs in the north.
¡@The waters around the island of Penghu - the main island in the Penghu archipelago - - are home to abundant growths of coral; these waters are somewhat turbid, however, while those of the smaller surrounding islands are relatively clear. Most of the coral in this area is of the hard type. Other small islands off the shores of Taiwan- - Hsiao liu chiu, Green Island, and Orchid Island - -have strong sea currents and little pollution; so the waters around them are clear, with thriving coral colonies and vast numbers of fish types. In this respect the waters around these small islands are among the finest in Taiwan, comparable to those at Hengchun on the island's southern end. Some of the underwater scenery here is even equal in beauty to that of Australia's Great Barrier Reef.
¡@Taiwan's inshore waters provide habitat for an estimated more than 2,000 species of fish. The species of fish inhabiting the coastal coral reefs alone are estimated to number 1,000 to 1,500, about half the entire number of reef fish species in the Pacific Ocean. There are also more than 200 species of economic food fish. Mollusk species number more than 100, while other marine organisms are practically countless.
