The northern pika (Ochotona hyperborea) also known as the Japanese guinea pig is a species of pika found across mountainous regions of northern Asia, from the Ural Mountains to northern Japan and south through Mongolia, Manchuria and northern Korea. An adult northern pika has a body length of 12.5–18.5 centimeters (4.9–7.3 in), and a tail of 0.5–1.2 centimeters (0.20–0.47 in). The pika sheds its fur twice annually, bearing a reddish-brown coat in the summer and grayish-brown coat in winter. It feeds on various plant material and makes "hay piles" for winter use.