Siberian Flying Squirrel

The Siberian flying squirrel is a small arboreal rodent with very large dark eyes, soft grey fur and a broad, flattened tail. A furred membrane stretches between each wrist and ankle; spreading the limbs turns it into a gliding surface rather than true wings. The underside is pale, and the face lacks the bold stripes of a chipmunk. Its compact head and short rounded ears reduce drag while moving between trees. (Wikipedia, Siberian flying squirrel account)

This squirrel occupies mature boreal and mixed forest from northern Europe across Russia into East Asia. It rests in tree cavities, is mostly active after dusk, and glides between trunks to avoid descending to the ground. Leaves, buds, catkins, seeds and berries make up much of the diet, with food sometimes stored in cavities. Females rear young in lined nest holes. Mongolia is not described in detail by the opened biological account, so no national habitat claim or viewing site is added. (Wikipedia, Siberian flying squirrel account)