---
title: "What the sources say about the Japanese Macaque | AnimalTracks.wiki"
description: "66 claims from the Japanese Macaque profile, each beside the words of the source that backs it."
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# What the sources say about the Japanese Macaque (*Macaca fuscata*)

> 66 claims from the Japanese Macaque profile, each beside the words of the source that backs it. A "..." marks a cut in a quote and [brackets] an insertion.

Profile: [Japanese Macaque](https://animaltracks.wiki/animals/japanese-macaque/)

## Japanese macaque. Primate Info Net, Wisconsin National Primate Research Center, University of Wisconsin-Madison.

https://primate.wisc.edu/primate-info-net/pin-factsheets/pin-factsheet-japanese-macaque/

| The page says | The source says |
| :--- | :--- |
| The world's northernmost wild monkey | the species nevertheless represents the northernmost wild populations of non-human primates in the world |
| also called the snow monkey | Japanese macaque, Japanese monkey, Snow monkey |
| lives farther north than any other wild non-human primate on Earth | the species nevertheless represents the northernmost wild populations of non-human primates in the world |
| ranging across Honshu, Shikoku, and Kyushu up to the Shimokita Peninsula at Honshu's northern tip | Of the four main Japanese islands, Hokkaido, Honshu, Shikoku, and Kyushu, Japanese macaques are found on all but Hokkaido ... The absolute northernmost Japanese macaque populations are found at the northern tip of the island of Honshu on the Shimokita peninsula |
| Males average 11.3 kg and about 57 cm in body length; females run smaller, at 8.4 kg and 52 cm | The average body weight of the Japanese monkey is 11.3 kg (24.91 lb) (M) and 8.4 kg (18.52 lb) (F) ... Average body length for males is 570.1 mm (22.44 in) and for females is 522.8 mm (20.58 in) (note: 570.1 mm and 522.8 mm rounded to 57 cm and 52 cm; the factsheet's header calls this 'Height' but its text says body length) |
| recorded eating more than 213 plant species | will eat a great variety of foods including over 213 species of plant |
| plus insects, fungi, eggs, and soil | Other main foods eaten include insects and soil |
| Mountain hawk-eagles and feral dogs have been recorded preying on them | Japanese macaques are preyed upon by several species including feral dogs and Mountain Hawk Eagles |
| raccoon dogs may too, especially on infants | raccoon dogs ( Nyctereutes procyonoides ) may be a predator of the Japanese macaques, especially infants (Iwamoto 1974) |
| in 1998 alone, people killed more than 10,000 of them | The annual kill surpassed 10,000 individuals annually in 1998 (Watanabe & Muroyama 2005) |
| Several provisioned macaques have also been observed washing sand off sweet potatoes in water | Several provisioned Japanese macaques have been observed washing sand off sweet potatoes in water and passing this behavior on to others |
| a habit that spread among a number of individuals within a troop and was described as "pre-cultural." | This behavior is described as being pre-cultural, having been picked up and spread among a number of individuals within a troop (Kawai 1965) |
| Macaques in wild and feral groups have been known to build snowballs and repeatedly handle stones in stereotyped ways, and to pass these behaviors on to others | Macaques in both wild and feral groups have also been known to construct snowballs, repetitively and stereotypically manipulate stones, and to transmit these behaviors to other individuals (Eaton 1972; Huffman & Quiatt 1986) |
| One study put the average lifespan of wild females at just 6.3 years | Actual average lifespan, however, is significantly shorter; with wild females living for an average of just 6.3 years (Takahata et al. 1998) |
| macaques are killed in Japan when their crop-raiding and run-ins with people become a problem, and the annual kill passed 10,000 in 1998, around a tenth of the estimated population | Japanese macaques are also killed in Japan when their crop-raiding and interactions with humans become a problem. The annual kill surpassed 10,000 individuals annually in 1998 (Watanabe & Muroyama 2005). This is significant because this annual kill represents around a tenth of the entire estimated population |
| Far shorter than the record ages suggest. | Actual average lifespan, however, is significantly shorter |

## Macaca fuscata (Japanese macaque). Animal Diversity Web, University of Michigan.

https://animaldiversity.org/accounts/Macaca_fuscata/

| The page says | The source says |
| :--- | :--- |
| In the wild, the oldest known male reached 28 and the oldest known female 32 | In the wild, the oldest known male Japanese macaque was 28 years of age. The oldest known female was 32 years of age. |
| Japanese macaques are generalist omnivores | Japanese macaques are generalist omnivores, and their diets change seasonally |
| fungi | Japanese macaques also opportunistically eat fungi |
| eggs | Animal Foods eggs insects |
| mostly fruit in summer and autumn | During the summer, especially June and between September and November, they mostly eat fruits |
| mostly flowers and some nectar in April and May | During April and May and from December to March, Japanese macaques eat mostly flowers and some nectar |
| a macaque that spots a predator gives a hollering call to warn the group | When a predator is spotted, individuals make a hollering vocalization to warm others in the group (note: source's own typo: 'warm' for 'warn') |
| Humans are their most lethal predator | The most lethal predator of Japanese macaques is humans |
| Females stay in their birth troop while males leave as they mature | Females do not leave their natal group, whereas males leave the troop as they mature |
| daughters inherit their mother's rank | Japanese macaques are nepotistic, meaning daughters inherit the rank of their mother |
| Subtropical to subalpine forests on Honshu, Shikoku, Kyushu, and a few smaller Japanese islands | inhabit subtropical or subalpine deciduous, broadleaf, and evergreen forests. They are found on three southern main islands of Japan: Honshu, Shikoku, and Kyushu, as well as a few smaller islands |
| from cool deciduous broadleaf forest in the north to evergreen broadleaf in the south; seen as high as 3,180 m | In the northern part of their range, they inhabit cool temperate deciduous broadleaf forests ... In the southern part of their native range, Japanese macaques live in evergreen broadleaf forests ... Although they have been spotted at elevations as high as 3180 m |
| Generalist omnivore: fruit, seeds, flowers, nectar, leaves, bark, fungi, eggs, and insects, shifting with the seasons | Animal Foods eggs insects Plant Foods leaves roots and tubers wood, bark, or stems seeds, grains, and nuts fruit nectar flowers Other Foods fungus |
| Because Japanese macaques are nepotistic: daughters inherit the rank of their mother, so a low-ranking mother's daughter starts low too | Japanese macaques are nepotistic, meaning daughters inherit the rank of their mother |
| high-ranking individuals get to food first and low-ranking females usually eat less nutritious food | High ranking individuals have access to food first, and thus low ranking females usually eat less nutritious food |
| dangerLevel: Medium | Negative Impacts injures humans (note: ADW's negative-impacts list; no source reports serious injury, so Medium not High) |

## Hori et al. (1977). Thermoregulation of the Japanese macaque living in a snowy mountain area. The Japanese Journal of Physiology.

https://doi.org/10.2170/jjphysiol.27.305

| The page says | The source says |
| :--- | :--- |
| meeting -20°C mountain winters | During the winter the monkeys are exposed to temperatures as low as-20•Ž |
| with long fur | The hairs from both areas are significantly longer in HV monkeys than those in indoorliving monkeys |
| huddles | Huddling is frequently observed on the windy and snowy days |
| in one valley, a hot-spring soak that may help keep it warm | Sitting in a hot spring also seems to show thermoregulatory behavior |
| temperatures down to -20°C | During the winter the monkeys are exposed to temperatures as low as-20•Ž |
| usually piles two to three meters deep | it is usually 2-3m deep |
| studied adult males from a provisioned troop at Jigoku-Dani | Nine male adult monkeys of one troop(Shiga A-troop),consisting of 87 monkeys living in Jigoku-Dani(Hell Valley)(about 1,000m)were used in the present study.Since 1963,this troop has been given provisions throughout the year |
| held a steady rectal temperature of 38.3°C to 39.6°C at air temperatures from -1.4°C to 28.3°C, with no increase in metabolic rate in the cold | Tre were maintained within the range of 38.3-39.6•Ž at Ta of-1.4-28.3•Ž,in spite of no increase in metabolic rate in the cold |
| Their hair was significantly longer than that of monkeys living indoors | The hair on the back and abdomen in the HV monkeys was significantly longer than that of Inuyama monkeys living indoors |
| the researchers suggested thick fur may account for their responses to the cold | It is suggested that the thick fur of HV monkeys may account for, if not all, the thermoregulatory responses of the Japanese macaque in snowy mountain areas |
| An earlier study shows what the coat is worth: macaques with clipped coats needed to raise their metabolic rate by 53% at 5°C and 100% at 25°C to keep their body temperature steady | Japanese macaques whose coats were clipped all over the body needed to increase their metabolic rate by 100% at Ta of 25•Ž and 53% at Ta of 5•Ž to maintain homeothermy,as compared with unclipped monkeys(TOKURA et al.,1976) |
| On windy, snowy days the monkeys often huddle | Huddling is frequently observed on the windy and snowy days |
| when resting in snow they flex both limbs against the belly, cutting heat loss from the sparsely furred chest, abdomen, and groin | in snow they prefer to take a peculiar posture when resting,both limbs are flexed and are compressed firmly on the ventral side of the body,thereby reducing the heat loss from the chest,abdomen and groin areas where the fur is sparser than that on the back |
| some macaques sit in a hot spring measured at 38 to 41°C | Sitting in a hot spring also seems to show thermoregulatory behavior.The water temperature in the pond was 38-41•Ž |
| called it a likely thermoregulatory behavior | Sitting in a hot spring also seems to show thermoregulatory behavior |
| noting from limited observations that how many sat in it, and for how long, seemed to track the weather | According to our limited observations during the short stay there,the number of animals sitting in the spring and the staying time in spring seems to be related to the weather conditions |
| in the snow season, low-calorie bark and winter buds when food is extremely limited | In the snow season,the availability of food is extremely limited, qualitatively and quantitatively.The wild monkey depends on the barks of broad-leaf trees and winter buds of deciduous trees which have low caloric value |
| Holds its body temperature steady in the cold with no rise in metabolic rate | no significant change in metabolic rate was observed at T a between-1.4 and 28.3°C, while the rectal temperature was maintained at normal level |
| apparently thanks largely to thick fur | the type of cold acclimatization in the HV monkey does not seem to be a metabolic one,but rather an insulative one determined largely by the increase in fur thickness |
| hot-spring soaking that may help it keep warm | Sitting in a hot spring also seems to show thermoregulatory behavior |
| often huddles on windy, snowy days | Huddling is frequently observed on the windy and snowy days (note: vibe.reason) |

## Nakamichi et al. (1995). Interactions among adult males and females before and after the death of the alpha male in a free-ranging troop of Japanese macaques. Primates.

https://doi.org/10.1007/bf02382861

| The page says | The source says |
| :--- | :--- |
| In one free-ranging troop, the alpha male kept his rank for 17 years | in a free-ranging troop before and after the death of the alpha male, who died at 28 years of age after occupying his rank position for 17 years |
| relying on female support | These results indicate that the alpha male maintained his position by depending on female support and particularly that of the alpha female |
| held it even as his health failed before his death at 28 | who died at 28 years of age after occupying his rank position for 17 years. The alpha male’s physical condition had deteriorated due to his extreme age for several months before his death. However, he maintained his alpha position |
| When the second-ranking male attacked him, the alpha female rescued him | When he was attacked by the second-ranking adult male, he was rescued by the alpha female |
| after that he screamed for her support whenever that rival approached | Thereafter, whenever the second-ranking male approached him, the alpha male screamed for the alpha female’s support |

## Ventura et al. (2005). Differential effects of ambient temperature and humidity on allogrooming, self-grooming, and scratching in wild Japanese macaques. American Journal of Physical Anthropology.

https://doi.org/10.1002/ajpa.20125

| The page says | The source says |
| :--- | :--- |
| In one study of wild Yakushima macaques, scratching and, to a lesser extent, self-grooming rose with heat and humidity, while time spent grooming others was essentially unaffected | in wild Japanese macaques (Macaca fuscata yakui). The amount of time monkeys spent allogrooming was essentially unaffected by variations in ambient temperature and relative humidity. Frequency of scratching and, to a lesser extent, time spent self-grooming significantly increased when ambient temperature and/or relative humidity increased |
| which the authors linked to that grooming having a social function as well as a hygienic one | These results are interpreted in relation to the differences in ultimate function that exist between allogrooming (with both hygienic and social functions) and self-grooming and scratching (with a solely hygienic function) |

## Nakamichi & Shizawa (2003). Distribution of grooming among adult females in a large, free-ranging group of Japanese macaques. International Journal of Primatology.

https://doi.org/10.1023/a:1023744515134

| The page says | The source says |
| :--- | :--- |
| In one large, provisioned, free-ranging group, each adult female groomed on average 10 of the other 84 females | adult females in a large, provisioned, free-ranging group of Japanese macaques ( Macaca fuscata ) at an individual level. Each female groomed on average 10 of the other 84 females |
| 54% of them gave at least half their grooming to a single partner | 54% of them devoted ≥50% of their grooming to a single female grooming partner |
| Choosy. | which indicates that most females had grooming interactions with a relatively small subset of available females |
| Most grooming bouts, 65%, were between relatives, yet a quarter of the females groomed unrelated females disproportionately | Although 65% of the total grooming bouts were between related females, 25% of females disproportionately groomed unrelated females |

## Watanabe & Tokita (2020). Macaca fuscata. The IUCN Red List of Threatened Species 2020: e.T12552A195347803.

https://doi.org/10.2305/iucn.uk.2020-2.rlts.t12552a195347803.en

| The page says | The source says |
| :--- | :--- |
| Least Concern | IUCN Red List category: Least Concern (LC). (note: IUCN category verified through GBIF's copy of the Red List assessment, per docs/fact-check.md) |
| The IUCN Red List rates the species Least Concern | IUCN Red List category: Least Concern (LC). |