A wide difference in altitudes (a variance of 3,600 meters from the lowest to the highest point), sheer cliffs, and deep valleys in the Yushan National Park lend to the park highly unstable weather conditions. Temperatures can vary from warm to cold at the same time at places relatively near to one another. Therefore, the diversity of plants found here is truly remarkable. While accounting for merely 3% of Taiwan's total land area, the park has fully half of Taiwan's native plant species growing within its boundaries. 

Vegetation in the park's alpine tundra areas, such as that found on Yushan, Mabolasih, Siouguluan, and Guanshan, can be categorized as sub-alpine plain and scrub and grasses found near to the ridge. Below the alpine tundra is dense forest cover and associated vegetation fed by a significant volume of rainfall every year. The high altitude forests consist of five different types, namely: sub-alpine coniferous (>3,000 meters – cedars and firs), cold temperate coniferous (2,500~3,000 meters – hemlock and spruce), and warm temperate coniferous / deciduous mix (1,200~2,500 meters). Lower elevations are mostly occupied by warm temperate rainforests, within which camphor is a typical species. This elevation has interspersed coniferous and secondary- growth deciduous trees.

The Yushan National Park is populated by nearly all of Taiwan's indigenous low, mid, and high altitude wildlife. These include the Formosan salamander, a rare amphibian that lives in shaded areas of forest below 3,500 meters. It has been an inhabitant of Taiwan since at least the last Ice Age. Also, between the months of March and May, visitors have the chance to see processions of butterflies fluttering through mountain valleys.

Fauna 1
Yushan National Park is located at the essential area of the Yushan and Central Mountain Ranges.Due to the varied topography and climate,the plants are prolific and form original forests. This environment gives rise to the magnificent and and beautiful animal world in the area.Preliminary investigations reveal that there are 130 species of birds,28 species of mammals,17 species of reptiles,12 species of amphibians and 186 species of butterflies in Yushan National Park.Among them are some unique species found only in Taiwan,e.g. the endemic Hemiyzon taitungensis and Varicorhinus tamusuiensis (Oshima) are two unique fish species living in the Lakulakuhsi area. 

From day to night,summer to winter,the animal communities keep changing.These changes proceed seasonally,daily or even hourly.In the evening,the diurnal animal give place to the nocturnal animal and at daybreak,vice versa.Some animals stop their activities and disappear at different times.Some highland lagre mammals,such as Formosan Serow and Formosan Sambar ,are also known to migrate. 

The essential large mammals in Taiwan can all be found in Yushan.Formosan Serow is one of the common highland mammals. They live on tender leaves,grasses and fruits.They walk comfortably also steep,rocky slopes in elevations from 1000 to 3500 meters. This dangerous topography helps Formosan Serow to escape easily from its predateors.

Sometimes they smear the scent gland secretions on tree trunks to signify their territory. 

In Autumn ,Formosan Serow migrates from highlands to lowlands in order to get enough food and to avoid the severe cold.In Spring,they go back to the higher and steep mountain slopes.At this times,the snow melts,plants bud,and the highlands can provide enough food again.This seasonal migrating habit of animals thus protects the plants from becoming overconsumed. 

Formosam Black Bear,has a five toed paw with long and curved nails that can dig into the earth in its search for food. They also have lagre molars, which are good for grinding vegetables.They are therefore omnivorous.Formosan Black Bear does not hibernate. The most distinct feature is that they have white curved spots on their neck.With the exception of human beings,the bear has no natural enemies. Their living environment,however,has already been destroyed by human activities. So,Formosan Black Bear is a rare animal in Taiwan now. 

From plain to highland,Formosan Sambar can live in many environment.Optimally they prefer forest areas with an ample water supply,numerous grasses at 1500 to 2500 meters in elevation. Like sheep,Formosan Sambar is a ruminant and gregarious.They move quickly and can stop immediately and change dirctions during fast running Their hooves can also secrete different scents to warn or to communicate with other deers. 

Their coats change twice a year in order to adapt to climatic changes. The winter hair is dark and thick,while the summer hair is reddish brown and thin. 

Below 3400 meters in elevation,lives Formosan Rock Monkey. A group of monkeys shows a high degrees of social organization. Usually they remain in trees,but sometimes they may move about on the ground.Their diet consists of fruits,tender leaves,insects and arthropods. Macaca cyclopsis (Swinhoe) is the unique and endemic species of monkey in Taiwan. 

The large mammals of the area are Formosan Serow, Formosan Black Bear, Formosan Sambar,Formosan Rock Monkey,Formosan Wild Boar and Formosan Reeve's Muntjac. There are also many small mammals such as Formosan Shrew,Formosan Field Mouse and Formosan Mountain Rat in this area.They live in the broad forests and high grasslands.Chinese Mink and Chinese Tiger Cat,are their natural enemies.The variety of animal species increases the stability as well as the complexity of this highland ecosystem. 

Birds can be found everywhere,from low valleys to high summits,in Yushan National Park 

Due to the stable climate and environment,the birds here, especially those living in the middle-elevation forest,do not migrate with the seasons.These birds,after long term adjustment to the environment,have their own living territories. 

Fauna 2 
During the glacial period,Taiwan was connected with mainland China. At that time ,birds emigrated from the mainland and gradually new species evolved.There are 15 endemic species of birds found in Taiwan.Among them, the most outstanding ones are Lophura swinhoii,(Swinhoe's Pheasant) Syrmaticus makado (Mikado Pheasant) and Urocissa caerulea (Formosan Blue Magpie) etc.. Due to the different altitudes and vegetation within the area, the species and numbers of birds differ correspondingly. General rules in this regard are:(1) As elevation increases the number of species of birds decreases.(2) As ample food and suitable living environments are provided, both the number of species and birds are numerous in the broad-leaved forest.

In winter,cold currents cause strong wind,low temperature, forst and snow. That forces the high-altitude birds,such as Alpine Accenter,Formosan Laughing Thrush,Coal Tit and Formosan Firecrest,to migrate downward to an altitude of 2200 meters. Jognstone's Bush Robin ,White-eared Sibia and Green-backed Tit,living in the mixed forest ,also migrate downward.

When thess highland birds migrate,they do not have any specific place to stay.They shift to places where food and environment are suitable.When then climate becomes warm,they fly back to the highlands to mate,nest and to nurse their young. During the reproductive period,brids have strong territorial instincts. Through fighting and competing,they build their own kingdom to secure food sources and to nurse their offspring. 

Brids are the most attractive animals in the forest.During the Spring, you may hear birds singing everywhere.Their song not only attracts female birds but also singals the extent of their terrirory. 

There are many types of grasslands,secondary and climax forests in this area.Different forests have different bird communities.Usually the birds are more numberous in the transitional zone,where more food is available.The forests are the common habitat for birds.Due to their different habitual natures,each species only makes use of a specific part of the forest. 

According to the altitude,three levels of habitat can be recognized. Since birds live in different levels and have their own specific habits,they can generally live together without conflict.However,migrates are usually cast out at the outer circles of the forests and may not enter into the territorires of the residents 

Above the forest zone,Alpine Accenter lives at the barren summit.The high elevation poses no threat to Prunella collaris.This bird has the highest elevation habitat among Taiwan birds.In addition ,small creeks in this precipitous and rocky mountainous area also provide some food for Brown Dipper and Turdidae. 

The reptiles in this area include snakes and lizards.They are unable to endure the severe cold so are distributed in areas of low elevation.The ancestors of reptiles lived in the water.In order to decrease water loss all reptiles have a specialized epidermis.Trimeresurus monticola orientalis,Natrix sauteri and Japarula swinhonis swinhonis are unique species of reptiles in Taiwan. 

The amphibians in Yushan National Park include Anura and Caudate The common frog and toad belong to Anura.They are distributed in the lowlands and live by water and moist shrubs.This is their common habitat.They usually seek food and mate during the night. Rana sauteri,Rhacophorus moltrechti and Rhacophorus robustus are unique species in Taiwan. 

Hynobius,which belongs to Caudate,inhabits the moist groud layer of the natural forests or alongside small creeks at elevations of 2000 to 3400 meters.The natural enemy of the amphibian is the reptile.During the Mesozoic,the ancestor of Hynobius inhabited a much colder area.This enabled them to escape from predation by reptiles which were the dominant and strongest animal on earth during that time. During the glacial period,Hynobius gradually moved southward and finally reached Taiwan.When the glacier retreated millionsof years ago, some of them were forced to move to the high mountains. There they were able to survive and to reproduce due to the fewer numbers of predators. 

Hemizyon taitungensis and Varicorhinus tamusuiensis (Oshima) are two unique species found in this area.The latter is also a new species to the world.These two highland freshwater fishes are extremely valuable research subjects. 

The insects are omnipresent in this area.Among them, and most attractive is the butterfly. butterflies are most active in areas near Tungpu hot spring and along the old passage from Patungkuan to Tungpu.Atrophaneura horishana ,Byasa tebanus and Papiko hoppo etc.are among the 23 unique species in Taiwan.