The reserve is a resting place for migrating birds not seen anywhere in Nepal. The endangered gharial, marsh crocodile and dolphins are also recorded in the Koshi river. Langtang National Park abounds in numerous vegetation types. Oaks, maple, various rhodendendrons, chir pine, fir, blue pine, hemlock and spruce are found here. This region is also an important route for migrating birds.
Conservation area extends from sub-tropical forests to high alpine vegetation.
Wildlife includes the endangered red panda, musk deer, Himalayan black bear, clouded leopard and possibly the snow leopard too. Parsa Wildlife Reserve was established as an extension of Royal Chitwan National Park, but having its own natural heritage. It encompasses the east-west Churia hills of chir pine, khair, sisso and silk cotton and drops down tho the subtropical monsoon belt of sal forests and sabai grasslands. The reserve supports wild elephant, tiger, leopard, sloth bear, gaur, blue bull, wild dog, sambar, chittal, hog deer, barking deer, langur, striped hyena, palm civet and jungle cat. The park ascends from 1800 to 4048 m and abounds in coniferous forests of blue pine, black juniper, West Himalayan spruce, oak and Himalayan cypress as well as Indian horse-chestnut, walnut, and Himalayan poplar.