The Ezo red fox (Vulpes vulpes schrencki) is a subspecies of red fox widely distributed in Hokkaido, Sakhalin, the Kuril Islands and the surrounding islands of Japan. The Ezo red fox's formal name, , was given to the subspecies by Kyukichi Kishida when he studied them in Sakhalin in 1924. Naming Ezo is a Japanese word meaning "foreigner" and referred to the historical lands of the Ainu people to the north of Honshu, which the Japanese named Ezo-chi. In the Ainu languages it is known as , , or . Description The Ezo red fox is somewhat larger than the Japanese red fox found in Honshu, Shikoku and Kyushu, and the outer part of the ear and the limbs are black. There are many similarities with continental red foxes. The Ezo red fox has 42 teeth: 6 incisors, 2 canine teeth, 8 premolar, 4 upper molar and 6 lower molars. Ezo foxes normally have eight nipples: a pair on the chest; two pairs in the abdomen; and one pair in the groin. Individual cases of seven to ten nipples are known. There are five digits on each forelimb and four on the back-leg, a total of 18. Ecology Ezo red foxes range widely from grassland to alpine belts in Hokkaido. They mainly eat rats, mountain hares, birds, and insects. They also eat fruit and nuts in autumn. In tourist spots and some urban areas, individuals feed on the street. They have also been observed feeding on the placenta of cattle in pastures or at disposal facilities. They dig holes or tunnels to make their lairs. The females give birth to kits in the early spring, grown and independent by late autumn. Males act independently and do not contribute to the raising of offspring. Diseases and parasites Ezo red foxes are especially prone to infestation by Echinococcus and helminths. These were introduced to Hokkaido via cultured silver foxes from the Aleutian Islands in the modern era. Echinococcosis is a tapeworm-type infection in Ezo red foxes. An infection cycle is maintained between Hokkaido's Ezo red fox and the field mouse. Since 1999 activities have been undertaken to reduce the infection rate by causing anthelmintics to be ingested by wild Ezo red foxes. Echinococcus worm eggs excreted with the faeces of foxes can be ingested by humans and cause echinococcosis. This can be treated if it is found at an early stage, but