The middle elevations of Beidawushan are famous for the cloud forest. It is the largest primary forest in southern Taiwan.
Why is it called a cloud forest? I think these photos can give you a hint:
Taiwan is one of the wettest places in the world, and due to the moisture come from the strait of Taiwan over the plains of Pingdong, the cloud forest is one of the moistest places in Taiwan.
The cloud forest is famous for the currently rare Taiwan yew (tsuga mairei). It is closely related to the Sumatran/Chinese yew (tsuga sumatrana) and is sometimes regarded as being the same species, but apparently skilled botantists can tell tsuga mairei and tsuga sumatrana apart. Most Taiwan yew trees were logged and, since they grow slowly and are difficult to reforest, have not recovered. Now they are a source of the anti-cancer chemical paclitaxel. This website has tons of information about Taiwan yew.
The forest is also home to the endangered Taiwan Plum Yew (cephalotaxus wilsoniana).
During my Beidawushan hike, I saw a mammal dart through the yew forest. While I’m not sure what it was, it was mostly likely a wild boar.
While hiking through the forest, I saw plenty of Formosan rock macaques, which are the only species of primate (other than humans) native to Taiwan. They are closely related to Japanese macaques.
Formosan Serows also live in the cloud forest. Though I did not see any serows on my Beidawushan hike, I have seen a serow in a different section of the Dawu mountains.
It was believed that there were no bears living on the slopes of Beidawushan until a Formosan black bear was spotted in 2013. The question is, did the bear wander down from its refuge near the Batongguan Trail (the part of Taiwan which is supposed to have the largest population of black bears), or had a local bear population been surviving in the forests of Beidawushan all along? In any case, it’s estimated that there are only about a thousand wild bears in all of Taiwan. They are very difficult to find, and the only person I’ve met who has seen one is a Bunun mountain porter. I have, however, seen bear scratches on trees.
The most mysterious animal of the cloud forest, of course, is the Formosan clouded leopard, the only cat endemic to Taiwan. It has been officially declared extinct. Officially extinct animals have been found before, such as the discovery of a breeding pair of the ‘extinct’ Chinese crested tern found in the year 2000, but so much effort has been put into finding the clouded leopard that there is almost no hope.
About 500 leopard cats, the only other feline native to Taiwan, are believed to still live in the Taiwanese wilderness.