Ice sheets formed repeatedly on the earth during the Pleistocene, the sixth of the seven epochs constituting the Cenozoic Era (the last 65,000,000 years of geologic history), and were the initiators of the animal immigration process. (The Pleistocene began 2,500,000 to 3,000,000 years ago and ended 10,000 years before our present time.)
The oceans fell as the vast ice sheets formed, and the then only 100-meter-deep trough between the Chinese main land and Taiwan Island emerged as a more-or-less dry valley between them.
Simultaneously at that time, the southeastern mainland and Taiwan were gradually covered by conifer forests, both the mountains and plains, amid average annual temperatures of only 8-11°C.
Fossils and modern evidences indicate that meanwhile, various temperate zone animals from the Chinese mainland's southwestern and even northern districts immigrated via the new land link to Taiwan. When the glaciers later withdrew and ocean waves played once more over the strait, the travels of animal life between Taiwan and the mainland ceased—that was around 16,000 years ago.
Warmer temperatures finally divested the island's plains of their conifer forests, compelling the associated wildlife to move to the hills. Fortunately, Taiwan offered vast and lofty highland areas, preserving sufficient conifer forests for the survival of the affected animals. So these mainland guests from the ages finally settled down in island mountains.
The special ecology of Taiwan's forest—mixed broad leaf trees and conifers, so distinctively different from those of the mainland—has affected the evolution over tens of thousands of years of Taiwan's fauna. The new generations evolved into new forms, animals distinctly different from their original continental cousins. Their biological appellation is "endemic species."
According to Professor Lin Chun-i of Tunghai University, of Taiwan's 61 present terrestrial mammals, 14 are endemic species, each specifically different from any on the Chinese mainland—or anywhere else in the world; 28 others belong to endemic sub-species, sharing some specific characteristics with their sub-specific brothers. We take a close look at some of the unique island animals below:
Among the 14 endemic mammalian species, 13 are in the categories of quadrupeds or bats. The sole exception is the Formosan macaque (macaca cyclopis Swinhoe), the only non-human primate found on the island. It is identified as having evolved from macaca mulatta, which immigrated from the Chinese mainland about 45,000 years ago.
The Formosan macaque, in comparison with the closely-related Japanese macaque, has a longer tail, lighter-colored hair on the head and buttocks, and darker extremities for its four limbs. Compared with the Rhesus (or East Indian) macaque, its head is more rounded and face more flat; its forehead is bare and the long whiskers are dark and scar-flike. While the tail of the East Indian Macaque is tapering and just about 3/4 foot long, that of the Formosan macaque is thick and over one foot long, capable of balancing and suspending. Additionally, its face and the callus on the hips are pink; a thin line of brown hair can be seen on the bridge of its nose; and the gray lower abdomen has distinct foxy spots. As a whole, its wooly hair is brownish gray, the tail dark brown, and its hands and feet nearly black. These are the characteristics that identify the Formosan macaque as an endemic species.
Unlike most of the island's native mammals, macaques are diurnal in activity; they are thus among the more readily observed. Found throughout the island where natural vegetation is present, generally speaking, they choose virgin broad leaf forests under 2,000 meters in elevation as their favorite habitats. At present, the mountain regions of eastern and southern Taiwan shelter most of their population.
Formosan macaques usually rest in trees, but sometimes, especially in rainy seasons, they sleep in caves or under overhanging rocks. They move up to the hills in springs and summers, and down in colder days, following seasonal changes in food sources—mostly vegetation.
And though they also eat insects, leaves, stems, fruits, and berries predominate in their diets. They feed according to fixed schedules, usually twice a day, once in the early morning and again at dusk. Occasionally, fruit farmers find them as uninvited and unwelcome visitors.
Female macaques bear young from the age of six, their fertility signaled when faces and buttocks turn bright red. During twenty-plus years of life, they give birth to at least 4-5 babies, usually one at a time. Pregnancy is about 150-160 days. Like human beings, the female macaques take care of their babies, which mature enough to start living independently at 4-6 months.
Sexual maturity of the male is later than the female, and one male may have many mates. Macaques live in large groups of approximately 20-30 headed by a dominant male. The social ranking is very explicit, and the dominant male has absolute command.
Macaque social behavior includes "dolling-up," cooperating in picking parasites from each other's fur, playing and fighting and other mischief, and communication via barks and body language-one such signal being a high-pitched alarm call given repeatedly by a male, followed by vehement shaking of the tree branches.
It is interesting to note that in swimming, the macaque adopts the human-like "crawl" stroke.
As a haven for this endemic species, the Provincial Forestry Bureau in 1972 set up a macaque preserve at Pakua Mountain in Changhua County, central Taiwan. Two groups totaling 60-70 individuals have now developed there.
Among medium to large mammals unique to Taiwan is the Formosan serow (capricornis crispus swinhoei Gray), a unique Asian mammal form. Long, thick hair accommodates the serow to low temperature in the high mountains. Short, stout limbs with jutties on the hoofs enable it to clamber nimbly among the steep, rocky cliffs.
Judging by chromosome numbers, the serow falls into two area species, one in Taiwan and Japan with 50 chromosomes, the other on the Chinese main land, Indo-China peninsula, and Sumatra, with 54 chromosomes. Differences in appearance divide the Japanese and Formosan serows into two subspecies, the Japanese larger, with longer hair, and color changes from winter to summer (absent in the Formosan serow).
The Formosan serow is basically brown; the hair on its knees and on the back of its neck is dark; that on its cheeks, throat, and frontal neck yellowish. Back-arched horns with delicate lines encircling the surfaces grow from its brow-top.
Except in Penghu, Changhua, and Yunlin Counties, Formosan serows are found wherever there are steep and rocky island slopes at elevations from 200 to 3,870 meters. High-altitude virgin conifer forests and disturbed slopes having good stands of miscanthus grass and native shrubs are their major browsing grounds.
Although they sometimes group in numbers of six or so, serows usually operate singly. They have a keen territorial sense, spreading a scent from a gland under the eyes on twigs or rocks to demarcate territories in which no intruders are permitted.
Serows give birth to one or occasion ally two young in summer, after a six-month pregnancy.
The Formosan sika deer (cervus nippon taiouanus Blyth) is believed to have become extinct in the wild state in 1969. But it exists in great numbers on domesticated deer farms. A project is in the initial stage to reintroduce sika deer into the wilds, centered on an experimental range-farm located at Nanjenshan in Kenting National Park at the southern tip of Taiwan.
The Formosan sika deer is about one and a half meters long and a meter high from shoulder to toe.
In summer, except for the white region covering the front of the neck, the abdomen, the buttocks, and the inner side of the limbs, it is a light chestnut color. A black line stretches along its backbone, dotted longitudinally on either side with around 20 white speckles. Similar speckles spot its trunk.
In winter, the hair turns light brown, the black line on the back becomes dark brown, and the white speckles become very indistinct.
The male sika deer sheds its antlers and grows new ones annually. From the second year on, one fork per year is added to each antler, to a usual maximum of 4-5. The antler spread reaches 40-50cm.
As is often the case, the male with the largest pair of antlers dominates the herd.
The sika frequents lowland flats along river courses and the lower foothill areas of mountains below 200 meters. Miscanthus grasslands offer succulent shoots for browsing and are its typical habitat.
The sika usually mates in autumn and after eight months of pregnancy, gives birth to one fawn between April and June the following year. Its family system, like the macaque, is polygamous.
The Formosan sambar (cervus unicolor swinhoei Sclater) is not as beautiful as the speckled sika, but surpasses it in physical build. Large sambar males weigh approximately 160 kg. and females, 140 kg. The male sambar has a pair of antlers as spectacular as those of the sika.
The brown hair of the sambar is dark in winter and yellowish in summer. A close look reveals a V-shaped stripe the color of palm fibers under each eye.
Sambar deer populations reach their greatest densities in high mountains set with ponds and marsh, especially at a confluence of broad leaf and conifer forests.
Breeding appears to be in summer with a single fawn born the following spring. In the wild, maturity is reached in the second year of life.
The sambar feeds on tender shoots and young leaves. When disturbed, it gives a shrill cry before fleeing.
Like the sika deer, sambars are now bred on a number of farms.
Formosan Reeve's muntjac (muntiacus reevesi micrurus Sclater) is a "barking deer," its series of short and loud barks a signal for danger. Hardwood forests with thick understories of miscanthus or bamboo are its major habitats.
The horns of the muntjac have no forks, but are small and straight. Its brown hair is thick and short; the tail is tiny; its limbs are very dark colored; a couple of dimples appear below the eyes. This is the smallest deer on Taiwan, with a shoulder-height of 30-40 cm. and a body length of about 50 cm.
Since the muntjac is very shy, visitors to the Taipei Zoo consider themselves fortunate if they glimpe one outside the shelter.
Muntjacs usually live in solitude, or occasionally in pairs. A single fawn is most common, but twins occur regularly.
The Formosan black bear (selanarctos, thibetanus formosanus Swinhoe), nicknamed the "doggy bear" by Chinese children, is the largest carnivore on the island although a mature bear measures only one and a half meters from tip to tail.
The hallmark of this bear is a white crescent on its chest amid glistening black hair.
As it is noctural in habit, the black bear ordinarily conceals itself in high mountain caves in daytime and goes out as hunger urges, feeding on anything edible-fish, insects, small beasts, and fruits and vegetables.
Although it howls and suggests attack when disturbed, the black bear usually attacks man only when trapped.
The Chinese leopard cat (felis bengalensis chinensis Gray), commonly called the "stone tiger" (a Taiwanese term that indicates a tiger that cannot grow) is also known as the "mountain cat," though it inhabits mountain areas only below 1,500 meters.
Except for its numerous spots and stripes and a larger physical build, the leopard cat looks like a domestic cat, but its temperament is by no means docile.
It is a hunter of squirrels, birds, snakes, frogs, and even such larger animals as the muntjac, deer, and the serow. When hunting, it often jumps on the back of its quarry, tearing open the anus and deboweling the animal. On occasion, domestic fowls also suffer its ravages.
The Formosan clouded leopard (neo-felis nebulosa brachyurus Swinhoe) is a large feline that may be extinct. Intervening between the tiger and leopard in form, it has not been reliably reported since a 1972 sighting, although some individuals are still believed to exist in the vastnesses of the Central Mountain Range.
The clouded leopard strongly resembles the common spotted leopard, but is smaller and is differently marked. Black stripes stretch from its head to the shoulders and back, and from the cheeks to the throat. The two sides of its trunk are dotted by black-rimmed, clouded speckles complicated by a few round spots.
Clouded leopards are nocturnal, solitary, and secretive. They usually lie on the low boughs of a tree in ambush and suddenly dash on their prey-macaques, muntjacs, serows, boars, and sambars. They kill by biting through the back of the neck, eating only part of a carcass and leaving the remainder.
The small Chinese civet (viverricula indica pallida Gray), as others of the family, excretes an offensive odor from an anal gland. Paradoxically, the base of the odor can be used by man to make perfume.
Because its fur has long been used in calligraphy brushes, the civet is commonly called the "pen cat" by the Chinese people. It is brownish gray with black stripes, its tail ringed with black circlets.
This nocturnal carnivore occurs in mountain regions under 1,000 meters and is found mainly in central Taiwan.
The Formosan gem-faced civet (paguma larvata taivana Swinhoe) is a lovely animal and the most docile of the three viverrines in Taiwan. It is kept in some households as a pet.
Its fur is brown except for white areas on the bridge of the nose and on the cheeks from which it derives its common name, the "white-nosed cat."
It is also known as the "black-footed musk" and the "fruit racoon" for its appearance, odor, and eating habits. Although it is omnivorous, fruit is its favorite, and it is a dexterous tree climber.
This lowland animal occurs below 2,500 meters and is found on nearby Orchid and Green Islands as well as Taiwan.
The crab-eating mongoose (herpestes urva Hodgson) honors its name via a voracious appetite for crabs. This viverrine lives along streams in low elevations and feeds on small stream-side animals as well as crabs, grasping its game and holding it to the ground. Occasionally, it preys on domestic fowl.
The fur of the crab-eating mongoose resembles a coir (reed) raincoat, and thus it is also called the "coir raincoat musk." In the face of an enemy, this raincoat changes shape-it bristles.
The Chinese Ottet (lutra lutra chinensis Gray) is a squirrel-like mustelid that lives along streams at altitudes under 1,500 meters and feeds on fishes, frogs, crabs, and water fowl. It is a very competent swimmer and fisher.
The Formosan yellow-throated marten (martes flavigula chrysospila Swinhoe) is a slender mustelid about 60 cm. in body length and with a 40 cm. tail. Its head, limbs, and tail are dark brown; from the throat to the upper part of the chest is bright yellow, and yellowish brown dominates the other parts.
An agile hunter, the marten is also known for its habit of raiding animals caught in traps or snares.
The golden weasel or Formosan weasel (mustela sibirica davidiana Miline-Edwards) is the local symbol for an old Chinese saying, "The weasel offers New Year's greetings to chickens," which clearly demonstrates untrustworthiness.
Relying on its tremendous agility and secretive habits, over the centuries, the weasel stole frequently into the residential quadrangles of ancient China to hunt mice, chickens, and other small animals without being perceived. Superstitious people regarded it as a kind of "fairy fox."
This mustelid has a slim figure and short limbs, and its yellowish-brown fur often turns white in the winter. It moves fluidly as a snake.
The golden weasel reaches its highest densities in the grasslands or open conifer forests at elevations from 1,000 to 3,000 meters.
The Formosan ferret-badger (melogale moschata subaurantiaca Swinhoe), along with other members of the mustelidae and viverridae—share to varying extents the ability to distribute a strong odor from an anal gland. Its body measures 30 cm. and the tail, 10 cm.
The ferret-badger is nocturnal and basically a hunter. But from time to time, it also dines on insects or fruit.
The ferret-badger's coarse body fur is grayish brown, with a white stripe along the back. The rear half of the tail is grayish white, and its face and abdomen are mostly yellowish white. It inhabits the lowland areas around Puli in central Taiwan.
The Chinese Pengolin (manis pentadactyla pentadactyla Linnaeus), having a long narrow snout and a long sticky tongue with which to lick up ants, is a toothless, scaly mammal that resembles other anteaters. But in biological classification, the other anteaters belong to the order edentate, while the pangolin is a member of the order pholidota and the family manidae.
In Chinese, the pangolin is called chuan shan chia (scaly mountain denizen). Its stout limbs and sharp claws enable it to excavate, and the thick, hard scales protect it from preying beasts. When an enemy is encountered, it curls its body to form an armored ball.
This nocturnal animal spends the day in burrows, especially along domesticated field borders. As an insectivorous animal, it does not cause crop damage and is quite compatible with agricultural activity.
The Formosan flying fox or Formosan fruit fox (pteropus dasymallus formosus P.L. Sclater) is the largest bat on Taiwan, with a body 20 cm. long. It has a big head, big eyes, and a protrudent muzzle, somewhat resembling a lemur (fox monkey).
Its habits are different from those of most other bats in at least two aspects. First, it feeds on fruit instead of insects. Second, it distinguishes things by sight rather than by sonar.
This species of bat inhabits tropical forests, not caves. A single pup is born between May and July.
Other endemic subspecies of mammals on the island include hares, flying squirrels, squirrels, bats, and rats.
Human intrusion, including the exploitation of mountain areas and heavy hunting over the centuries, has resulted in sharp declines in wildlife populations on the island, as elsewhere in the world. Recently, many people have recognized that "there is only one earth," and "the earth does not belong to man, but man belongs to the earth." And environmentalists and conservationists have organized on the island to preserve nature and protect wildlife, to assure that all of the unique species of Taiwan will be among the survivors.