Although Yangmingshan is an unsuitable habitat for large mammals due to its steep terrain and frequent human activity, the park's complex forest physiognomy still provides ideal nesting and feeding places for many medium and small wild animals. Mammals such as the Formosan rock-monkey (macaque), Formosan boar, Formosan hare, red-bellied squirrel, Formosan gem-faced civet, Formosan blind mole, spinous country-rat and Taiwan bandicoot rat are often to be seen in the park's conservation zones
Yangmingshan is home to a large number of birds of around 123 different species, and its accessibility has made it one of northern Taiwan's top bird- watching haunts. Birds proliferate in the thickly wooded area of Mt. Datun be tween Erziping and Xinbeitou, where visitors may view both birds and but terflies in abundance. The species of birds most commonly seen in wooded areas of the park include the Chinese bamboo partridge, Japanese white- eye, black bulbul, red-headed tree babbler and white-eyed nun babbler. Those more easily seen in grasslands and in shrubs include the white-backed munia, yellow-bellied prinia and vinous-throated parrotbill. In spring and autumn may be seen winter migrants such as the red bellied thrush and black-faced bunting. Common water birds include the white-breasted water hen, the little egret, the Taiwan whistling thrush, the grey wagtail and the plumbeous water redstart. Other striking wild birds of Yangmingshan include the Muller's barbet and the Taiwan blue magpie. Yangmingshan is also a wonderful place for butterflies, of which the park has over 180 species, mainly in the Mt. Miantian and Mt. Datun areas. Butterflies can be seen throughout the year along County Highway 101 A (Bailaka Highway) and on the trail between Erziping and Qingtian Temple. May to August is the peak season for butterflies at Yangmingshan, where the main species include: Papilio memnon heronus, Papilio bianor [akasago, Papilio helenus fortunius, Papilio protenor amaura (Papilionidae family); Parantica sitaniphonica, Parantica melaneus swinhoei, Euploea mulciber barsine, Euploea leucostictos hobsoni(Danaidae family); and Argyreus hyperbius hyperbius, Cyrestis thyodamas rormosana, Neptis philyra splendens (Nymphalidae family).
As you stroll along forest pathways, keep your eyes open for insects such as the unicorn beetle, stag beetle, metallicboring beetl and click beetle, and Yangmingshan's unique Dicranocephalus bourgoini as well as the preying man-tises, katydids, crickets, grasshoppers and stick insects to be seen on every side. In summertime the constant chirping of insects in the forest makes a wonderful natural music. There are over ten types of cicadas in the park, including the early-appearing Mogannia hebes, Rlhana ochracea and Platypleure kaempferi, together with Tanna sozanensis, Pomponia fusca and Cryp-totympana facialis which appear in July and August. Each species makes a different sound. Autumn is the mating season for katydids and crickets, whose busy chirping seems to fill the countryside.
Yangmingshan is home to no less than 53 species of reptiles, of which the Sauter's ground snake, red back pine root snake, common scaled water snake and flower snake are the most common. Yangmingshan's main venomous snakes are the Taiwan bamboo viper and the cobra. Visitors should be vigilant for their own safety in mountain areas. The most common species of lizards are the Japalura polygonata xanthostoma together with Sphenomorphus indicus and five-striped blue-tailed skink which are often seen in the undergrowth. There are 22 species of amphibians, including the tree frog, members of the Ranidae family, toads and the "ornate narrow mouth frog". The most numerous and widespread species are the "paddy frog", the "long-legged red frog", the Taipei green tree frog and the toad Bufo bufo gargarizans.