Sika deer dimorphism, with males invariably much larger than females. They can vary from tall at the shoulder and from in head-and-body length. The tail measures about long. The largest subspecies is the Manchurian sika deer ("C. n. mantchuricus"), in which males commonly weigh about and females weigh , with large stags scaling up to . On the other end of the size spectrum, in the Japanese sika deer ("C. n. nippon"), males weigh and females weigh . All sikas are compact and dainty-legged, with short, trim, wedge-shaped heads and a boisterous disposition. When alarmed, they often display a distinctive flared rump,
Sika deer suitable for farming and other human exploitation. Their range encompasses some of the most densely populated areas in the world, where forests were cleared hundreds of years ago. Their population status varies significantly in different countries. Although the species as a whole is thriving, it is endangered and extinct in many areas. Japan has by far the largest native sika population in the world. Though the exact population is uncertain, it is likely to be in the hundred thousand range and is still increasing, mainly due to recent conservation efforts and the extinction of its main predator, the wolf ("Canis