The Kai Dog, known in Japan as the Kai Ken, is a medium-sized spitz-type hunting dog from the mountains of the old Kai province, today's Yamanashi Prefecture. Hunters used these agile dogs to track deer, wild boar and other game through steep forest, and Japan designated the breed a natural monument in the 1930s. Its harsh double coat is always brindle, in black, red or medium shades, which earned it the nickname Tora Inu, or tiger dog.
Many Kai are loyal, alert and intelligent dogs that bond closely with their family and stay reserved with strangers. They are quick, athletic and sometimes surprisingly good climbers, with a strong prey drive and an independent mind. The breed is rare outside Japan, so adopters are more likely to meet a Kai mix or a similar Japanese spitz type than a registered dog.