This is the first such work on this region of high biodiversity in Eastern Himalaya-Mishmi Hills in northeastern India. Besides two flying squirrels of the genus Petaurista, which are new to science, a number of other significant mammal and bird records have been made. Blue-and-white Flycatcher and Gongshan Muntjac have been reported for the first time in India. The Leaf Muntjac as well as several species of galliformes were found to be widespread in and around the reserve. Small numbers of Tiger and Snow Leopard still occur in the area. At least 100 species of mammals and 312 species of birds have been listed. The area still has some fine natural habitats and perhaps several unrecorded small mammalian species, especially rodents. Poachers from Tibet (China) are a major threat in addition to normal conservation issues of habitat loss, hunting and developmental activities. Musk Deer (all species) and Black Bear are high on poachers'' agenda. Extension of the reserve up to India-China border as well as towards west (Mechuka area) and east (Chaglagam area) are strongly recommended.