The Japanese macaque is a monkey of medium size. They are also called the snow monkey because they often live in snowy regions. They have long, thick fur, of a brown or grey color. The dense fur contrasts with their faces, which have naked skin, as do their rump, which is red in adults. The male is larger than the female. Macaques have long whiskers and a beard, and their tail is short. As with other monkey species, the macaque has opposable thumbs, enabling it to take hold of things. It walks on its hind legs when holding something in its hands.
The Japanese macaque is the northernmost-living monkey. They are found on three of the four main Japanese islands: Honshu, Shikoku, and Kyushu. They inhabit evergreen and broad-leaved deciduous forest, from subtropical lowlands to sub-alpine regions of up to 1,500 meters high. This macaque can also survive well outside their natural range, for example, in Laredo, Texas, where a population was introduced.
Japanese macaques live in groups of 20-30, led by the dominant male. Females stay in their birth group for life, but males leave the group before sexual maturity. Females spend more of their time in trees, while males spend most of their time on the ground. The dominant male has a role in siring young, deciding where the troop should go, and protecting the troop from predators and other macaque troops. They are very sociable animals, especially the females who together groom and raise the troop's young.
The Japanese macaque eats smaller animals and plants, mainly fruits, berries, seeds, flowers and young leaves, picking them from the surrounding vegetation. They also eat insects, crabs and bird's eggs during the winter months.
Japanese macaques have a number of partners during a mating season, which lasts 4 to 5 months between September and April. Females usually choose a mate by his rank. Births occur between March and September, after a gestation period lasting 6 months. A single infant will be born. Baby macaques cling to their mother for two years.
The Japanese macaque face no major threats at the species level. Around 10,000 macaques are killed by farmers every year, protecting their crops and livestock.
According to IUCN Red list, the Japanese macaque is common, widespread and increasing in recent years. The total population is estimated at 114,431.
Japanese macaques consume a variety of insects and plants, and act as seed dispersers. They compete for some plants with Sika deer on Kinkazan Island, but when they climb trees to get the most energy sufficient leaves, in the process they knock down leaves, which the Sika deer eat. Japanese macaque serves as important prey species for mountain hawk-eagles, Japanese wolves, and raccoon dogs.