Social Spacing                
                                           
                       
  Troops of Japanese macaques utilize home ranges as large as 8 square miles (average 3 square miles) that sometimes overlap with other troops' ranges (Minnesota Zoo 2003). Food is distributed patchily throughout the range, making it necessary for the troop to move daily and seasonally to find food for the entire group. Each troop's home range has a core area that is used most frequently and that usually contains the richest food sources (Ikeda 1982). The macaques spend their time alternately in trees and on the ground. However, they are more vulnerable on the ground, so they typically sleep in trees for safety (Yotsumoto 1976).  
  Photograph courtesy of phototravels.net  
The macaques tend to disperse and reconvene several times a day to feed, rest, travel, and sleep. The direction of the troop within its range is determined by the alpha male and probably a few females. Two types of movement have been observed: rapid, processional movement, and slow movement that alternates with feeding, grooming, and brief resting periods. The macaques usually travel in the trees when they move short distances, but they move along the ground during longer journeys. The troop chooses a different arboreal sleeping site each night (Yotsumoto 1976).
                                     
The macaques rest in three different ways as well. Intensive resting occurs when they remain in one place for several hours. During this type of resting, the macaques often form grooming parties of 3-4 individuals. Playing and fighting are most frequent
 

during intensive resting times as well. In other instances, the central part of the troop (composed of females, infants and juveniles, and the dominant and subdominant males) will rest while the peripheral males continue to feed. Thirdly, while the troop is moving, several macaques may rest on the ground for short periods and then catch up to the rest of the troop. In the winter, macaques prefer to rest in open, sunny areas to warm themselves, and in the summer they rest in ravines or in treetops to avoid the sun. The macaques rest equally in the trees and on the ground during the autumn, but as the weather gets colder, they rest and groom more often on the ground because it provides a more open, sunny space. The same trend in arboreality is seen in playing, fighting and sexual activity. The troop also sleeps in the treetops, choosing a different sleeping site each night (Yotsumoto 1976).

  
   
Photograph courtesy of phototravels.net  
Seasonal changes in the macaques' activity seem to correspond to seasonal changes in food supply and atmospheric temperature. The macaques do not travel very far in the spring, when food is plentiful, but when summer arrives they move more often in search of food. During autumn, they eat frequently and in large quantities to store fat for the winter months, but since food is so abundant during this time of year, they do not need to travel to many different feeding sites each day to find enough food. In the winter, the macaques travel much less frequently in order to conserve energy (Yotsumoto 1976).  
 
Observational studies conducted with the Shiga C troop help to explain a troop's movements within its range. Many members of this troop were captured in 1974 to reduce crop damage in the area, and the behavior of the remaining troop members reflected the decrease in numbers. The troop's home range after the 1974 capture was only 56.8% of what it had been before the capture and included the areas of the range with the richest food sources. However, the troop continued to utilize the same core area of its home range because it supplied a large amount of food for the troop (Ikeda et al., 1973 as cited in Ikeda 1982). The troop spent longer periods of time in one location after the capture, and the average distance it traveled per day decreased.   In addition, prior to the capture the troop had been observed traveling through its range in a rhythmic pattern, but this pattern was not maintained after the capture. It is believed that the reduction in use of home range area occurred because the troop no longer needed to have such a large home range in order to meet its food requirements. Because of its lower numbers, the troop was able to use the resources in one area for a longer period of time before exhausting them. In addition, by spending most of its time in areas with the richest food sources, the troop was able to minimize the amount of travel it needed to find food, and thus used a smaller home range. (Ikeda 1982)
During the study, the Shiga C troop utilized different portions of its home range during the different seasons based on availability of food, changes in vegetation, and proximity of other troops. In the winter, the troop used a home range of 1.23 square km. Because of the snow cover, the troop could not feed on grasses, and trees were its only food source. However, because food becomes scarce in the coniferous forests, the troop moved to lower altitudes in the spring. During springtime, the portion of the home range used by the troop was located in lower altitudes, extending 1.46 square km. In the summer, the troop utilized a home range of 1.69 square km in the higher altitudes of its range. During this time of year, the coniferous forests in the higher altitudes have dense bamboo scrub, providing food for the macaques that is not available in wintertime. In autumn, the troop moved again to the lower portion of its home range and used 1.21 square km. The home range of the troop was larger in snowy areas (because of food scarcity) and smaller in non-snowy areas (because of increased food availability).  The winter and summer home ranges coincided quite a bit, as did the spring and autumn home ranges (Wada 1980).
    Photograph courtesy of phototravels.net

Because food is most plentiful and of highest quality in autumn and spring, the Shiga C troop was able to occupy essentially the same home range as the Shiga B2 troop during these two seasons without significant conflict. However, the two troops diverged in the summer and winter, no longer sharing resources because of the decreased availability of food (Wada 1980).
 
   
  In the Hakusan Mountains, snow is so heavy during the winter that troops of macaques must descend to a lower portion of their range. But because so many must share the same resources (which are scarce at this time of year even for one troop), they engage in more intertroop agonistic behavior while sharing the same range (Wada 1980).  
   
    Photograph courtesy of phototravels.net
Several transplanted troops in the United States live in areas that are designed to mimic the troops' natural home ranges. At the transplant site for the Arashiyama West troop in Laredo, Texas,  the troop lives in a 42 ha./5575 square meter enclosure (the home range the troop utilized in Japan was 4000 square meters), enclosed by an electric fence. In the enclosure are four shade platforms and two sleeping and shade towers, designed to resemble the troop's natural range as closely as possible.(Clark 1978). However, a troop in Oregon is kept in a much smaller space. The Oregon troop is confined in a .8 ha enclosure and does not have the central-peripheral social organization of most Japanese macaques (see the Social Organization page) (Alexander & Bowers 1968, as cited in Clark 1978). Its members are very aggressive and not well controlled by the alpha male because the close confinement keeps the alpha male from engaging in many of his characteristic responsibilities that normally keep the troop under control. It is believed that the confinement to a small space (not the stress of transplantation itself) causes the increased agonistic behavior. Thus, it is evidently important to the functioning of a troop that it has adequate space in its home range (Clark 1978).
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