The Natural Environment of Taiwan

Taiwan is a small island with a broad range of environments. Only 35,570 square kilometers in area, or roughly twice the size of the big island of Hawaii or half of Ireland, Taiwan is located one hundred and fifty kilometers off of the southeast coast of mainland China, between cool-temperate Japan to the north, sub-tropical south China to the west, and the tropical Philippines and Indo-Malayan islands to the south. This location, combined with a tall range of mountains, with more than two hundred peaks over 3,000 meters, supports a diverse flora of over 4,000 vascular plant species and a spectrum of six forest types. This range of environments in turn supports a rich fauna. Sixty-one species of mammals, more than 400 species of birds (about 40% resident), 92 species of reptiles, 30 species of amphibians, 140 species of freshwater fish, and an estimated 50,000 insect species,' including more than 400 species of butterfly, are known to occur here.

Taiwan is dominated by forested mountains. Almost three fourths of the country is slopeland (lane over 100 meters elevation and over 5% slope), and nearly half of the total area of the main island is above 1000 meters. The lowlands, especially the coasts, are important habitats for seabirds and for wildlife associated with the few remaining undisturbed patches of tropical strand or mangrove trees. Almost all flatland on the island' however, and an increasing amount of slopeland is intensively cultivated. The majority of cultivated land is below 500 meters on the western plain of the island, while the mountains are sparsely inhabited and the home of the majority of Taiwan's wildlife.

In the north of the island, the low mountains near the Taipei basin contain several of the island's endemic species or subspecies, including the emerald tree frog and Taipei green tree frog. These mountains are an especially good habitat for amphibians, since the northeast winter monsoon wind lifts moisture laden air from over the warm Japan sea current and blows it up the mountainsides, where it cools and condenses, releasing precipitation over the subtropical forest.

South of Taipei and on the western flank of the Central Mountain Ridge lies the Tahsueh Shan group of mountains, containing the second highest peak in Taiwan, Shei-Shan or “Snow Mountain,” at 3884 meters in height. This mountain group also receives heavy precipitation in the winter, with the higher peaks receiving it in the form of snow. The area above 2000 meters is home to the Formosan black bear, the largest land mammal on the island. Distinguished by a white V-shaped crescent on the chest, this omnivorous bear has long curved nails which help it dig into the ground in search of food.

The Central Mountain Ridge, or  "backbone ridge" of Taiwan runsn parallel to the island' axis (north north-east to south south-west) and contains the majority of Taiwan's high peaks. Consisting primarily of Eocene slate and limestone, this range contains the largest amount of natural forest remaining on the island.

At the laitute of the Tropic of Cancer, the Central Ridge has on its western flank the Yushan mountain group, dominated by Yushan, or "Jade Mountain," which rises to 3952 meters, the highest peak in East Asia. The slopes of the Yushan group, ranging from 300 meters upward, contain a broad represent of Taiwan's fauna. Inhabitants of the slopes include the Formosan macaque, wild boar, sambar deer, muntjac, the Chinese pangolin, Mikado pheasant, Swinhoe's pheasant, and several species of endemic babbler. There also is the alpine accentor or alpine hedge sparrow, known for its presence at the rocky summit of Yushan. In all, 28 species of mammals, 130 species of birds, 17 species of reptiles, 12 species of amphibians, and 186 species of butterflies have been recorded in the area.

One amphibian, the small Formosan salamander, lives alongside creeks from 2000 to 3400 meters. This species is considered a glacial relic whose original home is much further north than Taiwan, and only the cool temperatures of the high mountains have allowed it to survive here.

South of the Tropic of Cancer, the mountains begin to fall in altitude, and the climate changes accordingly. The lowlands east of the southern mountain of Tawu (3090 meters) may be the last refuge of the Formosan clouded leopard. Little is known about these cats. They are partly arboreal and prey upon monkeys, deer, muntjac, and serow. The last official sightings occurred in the early 1980's, and it is not certain that the Formosan clouded leopard still exists in the wild.

The region near the south tip of the island is an interesting mix of tropical rainforest and coral rock outcroppings. In undisturbed areas below 900 meters, there exist 19 of the 28 plant genera regarded as characteristic of the original tropical rainforest between the Asian continent and Australia.

Included are Ficus, Diospyros, Dysoxylum, and Syzygium. Rich in lianas and epiphytes, this forest is subject to constant high temperature and humidity, with an annual rainfall exceeding 2000 millimeters.

The protection of Taiwan's natural ecosystems is a unique and difficult challenge. Mountainous topography and the different forest types have combined with large scale human development to create ecological islands within the physical island that is Taiwan. The high mountain region, simply by its ruggedness, is the one area still maintaining much of its environmental integrity. Still pressure from economic interests threaten even the few remaining pocket of a wildlife habitat.

Taiwan's commitment to long-term preservation is, in reality, only ten years old. The strength of that commitment will be tested in the coming decade, and the result will be the fate of the island’s rare and endangered plants and animals.