The Rukh Balu is an unknown species of bear inhabiting the Himalayan Mountains of Nepal. The Rukh Balu is described as being similar to Tibetan Brown bears, but much smaller, only being about two feet long. They have black fur, small premolars, and are more agile and arboreal, and construct elaborate nests in trees. They're herbivorous, only eating fruit and during the monsoon season— corn. Its footprints resemble a juvenile black bear, but with a claw on the side of the paw.
The first mention of it was by Thomas Oldham, who gave it the name Selenarctos Arboreus. In 1983 and 1984 Daniel Taylor-Ide and Robert L. Fleming gathered reports from villagers in the Barun Valley that two different types of bears lived in the area: the Asiatic black bear and a smaller, more agile, arboreal species called the Rukh Balu or "tree bear." in English.