Japanese macaque

The Japanese macaque is the northernmost primate on Earth and the only one that lives in snow.
Japanese macaque (Macaca fuscata) uses hot springs in winter to stay warm, helping it survive harsh conditions.
A young female named Imo taught the troop to wash sweet potatoes in water, and the habit was passed on to later generations.
The Japanese macaque takes a long time to learn how to drink from a cup, spilling water on itself and around, but once it learns, it becomes a source of pride for its owner.
In captivity they have lived more than 30 years.
They eat bark and buds in winter.
Macaques can swim more than half a kilometre.
The fur thickens in winter.
Young macaques play with snowballs.
The main threat is conflict with humans.

Age

Japanese macaques have a typical lifespan of 20 to 30 years, with a maximum recorded lifespan of 38 years and 6 months, and a theoretical lifespan ranging from 19 years and 3 months to 38 years and 6 months. The species reaches sexual maturity between 3 years and 1 month and 5 years and 1 month of age, and the young are born with their eyes open. They begin walking between 2 weeks and 1 month and 2 weeks old. The embryo develops inside the mother for approximately 173 days and does not feed independently. The infant drinks its mother's milk and learns from the group, remaining completely dependent on adults for a period lasting from 1 day to 2 years. An adult Japanese macaque participates in group life, searches for food, and can reproduce, during a stage that lasts from 4 to 30 years.

Phenotype

The young Japanese macaque has thick fur that helps to retain body heat, and the skin on its face and buttocks is bright red. Adult snow monkeys also possess thick fur covering their entire body except for the face and buttocks, which protects them from severe cold; the skin on the adult’s face and buttocks is bright red and lacks fur. The species has five skillful fingers on each of its hands, enabling it to climb trees, gather food, and use simple tools, and a short tail assists with balance.

Physiology

Japanese macaques have a body length ranging from 47 to 60 centimeters; their mass varies from 6.55 to 8.38 kilograms. The embryonic stage involves individuals with a body mass from 1 to 400 grams and a body length from 1 millimeter to 10 centimeters. During the infant stage, the young have a body mass from 400 grams to 4.5 kilograms and a body length from 25 to 55 centimeters. Adult Japanese macaques exhibit a body mass from 10 to 14 kilograms and a body length from 53 to 60 centimeters.

Habitat

Japanese macaques inhabit flooded meadows where water frequently covers the ground and there is abundant grass, tropical moist forests with consistently high temperatures and humidity and large trees and vines, and temperate mixed forests with summers that are warm and many oak, birch, and maple trees. The species lives on land and in forested areas, experiencing climates with cool summers of 15 to 20 degrees Celsius, very hot summers exceeding 25 to 30 degrees Celsius, and consistently high humidity with frequent rainfall; some areas have cool summers with abundant rain and snow in winter, while others experience warm summers with abundant rain and snow in winter. Japanese macaques are found at elevations up to 1.5 kilometers above sea level.

Shelter

Japanese macaques inhabit trees or mountainous regions and do not have permanent or long-term shelters. The species does not use a fixed den site, but instead finds temporary resting places and protection from the cold. These snow monkeys utilize bark as a material for shelter. The purpose of these temporary shelters is for rest and protection from cold temperatures.

Geography

Japanese macaques inhabit the Palearctic, Indomalayan, and Neotropical biogeographical realms. The species is found in the evergreen forests of Nihonkaya and mountainous deciduous forests of Nihonkaya.

Feeding

Japanese macaques are omnivorous, collecting and consuming plants, fruits, leaves, seeds, insects, and occasionally small animals. The species obtains food by hand and sometimes uses water for cleaning; their diet includes fruits, leaves, seeds, bark, insects, small vertebrates, cones, and berries. They consume a daily amount of food ranging from 150 grams to 400 grams, with young macaques relying on milk for nourishment. The species’ prey includes beetles, butterflies, flies, Hymenoptera, bedbugs, Orthoptera, dragonflies, stoneflies, Plecoptera, and decapods. Japanese macaques are preyed upon by clouded leopards. In some cultures, the species is consumed as food, but it is not considered halal or kosher.

Reproduction

Japanese macaques reproduce sexually, with the female carrying a single offspring for about six months and providing long-term care. The gestation period is five months and three weeks, and a litter consists of one to two young. The species develops on land, outside of bodies of water, and young develop in nests built on or near the ground. These nests are located directly on the surface of the ground. Only the mother displays parental care for the offspring. Live young are born on land, not hatched from eggs or larvae. Sexual maturity occurs between three years and six months and seven years. The interval between reproduction is one to two years. Mating frequently occurs during colder periods.