Some spacing relations among the central males of a transplanted troop of Japanese macaques (Arashiyama west)

In February, 1972, a troop of 150 Japanese macaques was tranplanted from Kyoto, Japan, to Laredo, Texas, USA, after 20 years of study in Japan. As part of the general adaptation of the troop to its new environment, spacing behavior was observed in the central adult males [by independent rank, (1)Dai, (2)W, (3)Bus 62, and (4)Kojiwa 59]. Spot checks of locations, vertical space use, mobility patterns, and paths to and from a box of apples suggested that the major influences on spacing were rank, personality and history, social interactions, and several environmental factors (availability of vertical space, water, and shade, extreme heat, daily provisioning, etc).Dai exceeded the other males in use of vertical space, rate and distance of travel, and proximity to the apple box.W confined his high use of vertical space use primarily to one structure. His distance and rate of travel were low, and he maintained the greatest distance from the apple box.Bus 62 ranked second in use of vertical space, distance and rate of travel, and proximity to the apple box.Kojiwa 59 frequently changed sites in his use of vertical space. His distance and rate of travel were low, and he maintained long distances from the apple box.     

Population dynamics of Arashiyama west Japanese macaques

Demographic data have been collected on the Arashiyama Japanese macaque population from 1954 until the present, through the fissioning of the original group into two parts in 1966, and through the translocation of one of the two groups to Texas in 1972. Population dynamics are reported for the Arashiyama West group in Texas during 1972 to 1979 and then compared to data from Japan. After a short period of adjustment for the translocated group, during which time natality rates were relatively low and mortality rates were relatively high, many aspects of population structure, birth rates, and survivorship showed trends similar to those observed in Japan. This suggests that both long-term homeostatic processes and shorter-term responses to environmental fluctuations are significant to the study of nonhuman primate demography.     

Food adaptations of a transplanted Japanese macaque troop (Arashiyama West)

In 1972 Arashiyama West troop of Japanese macaques was transplanted to southcentral United States and kept in semi-free ranging conditions. The new environment provided an opportunity to assess aspects of the species' adaptive potential. About 1,500 feeding observations were made monthly over 6.5 months. Unlimited provisioned food was available, but monkeys utilized native plants immediately and use increased until it included 50+ % of the diet by weight. Shrubs provided 75% of foods in first month and 32% thereafter. Sorghum comprised 25% in May–July. Soil, arthropods, fungi, bulbs, and roots each comprised less 5%. Between 21 and 37 foods were utilized monthly. Monthly food uses corresponded to availability. Many food plants required unique handling by monkeys. Four general adaptive responses to potential foods are described. Evolution has clearly shaped the Japanese macaque into a highly omnivorous and behaviorally flexible animal.     

Mirror responses in a Japanese macaque troop (Arashiyama West)

Behavior toward two mirrors in the field was observed in the Arashiyama West troop ofMacaca fuscata. Counts of visits to the mirrors, plus scan and focal animal sampling were used. Some animals were marked with fluorescent paint to test informally for self-recognition. A relatively high mean frequency of visits to the reflecting side of both mirrors by all age classes, ranks, and sexes was recorded. There was no age difference in frequency of mirror visits per sample but adults spent more time per visit than subadults who in turn spent more time than juveniles. There was no indication of self-recognition by paint-marked animals. Mirrors appeared to be used to monitor the reflected scene and to look at the self-image. Social behavior in the mirror zone that was not directed toward the mirror was common to all age classes. Species-typical behavior directed toward the mirror was seen in younger animals but very seldom in adults. No threat displays by any animal were observed. We suggest that for adults the mirror image was not seen simply as another monkey.     

Behavioral patterns of estrous females of the Arashiyama West troop of Japanese macaques (Macaca fuscata)

This report contains detailed data on the sexual behavior of the 60 sexually mature females of the Arashiyama West troop of Japanese macaques. The study group was a natural troop transported intact in 1972 to a ranch in South Texas. Since transplantation, the monkeys have been free to roam and feed within a 42.2 ha enclosure. Analysis of data collected on the 140 monkeys that composed the troop during the 1973–74 and 1974–75 breeding seasons revealed: (1) Female-male mounting is an important aspect of Japanese macaque sexual behavior; (2) All females had preferred partners and most avoided both heterosexual and homosexual interactions with close kin; (3) Pubescent and adult females exhibit different patterns of sexual behavior; (4) Pubescent and adult females were affected somewhat differently by the transportation from Japan to their current home in South Texas. These behavioral patterns and their implications are discussed. The study was partially supported by PHS Biomedical Science Grant 50-262-1112.     

Changes in dominance rank and division of a wild Japanese monkey troop in Arashiyama

This article forms the second report on the Arashiyama troop of Japanese monkeys and concerns a troop division which took place in June, 1966, and various problems of rank and consanguinity which accelerated the division. (1) The hypothesis advanced in the first report has been verified; (2) at the time of troop division, several consanguineal groups formed one unit; (3) among 16 consanguineal groups, those from 1st to 7th in rank joined the A troop, while those from 8th to 16th joined the B troop; (4) dominance relation between the two division troops was B troop>A troop, reflecting the former ranking between the leader males of the two troops; (5) shifting of monkeys from one troop to the other after division occurred frequently, but males began to make their own movements when they attained 4 or 5 years of age and rarely moved together with their mothers or other consanguineous-relatives; (6) monkeys which were continuously in the same troop after division almost always obtained higher ranks than did monkeys who frequently shifted from one troop to the other; (7) after division, some males joined neither of the two division troops but formed a group, a so-called all-male group or male party, and moved about independently.     

Alliance formation in a free-ranging troop of Japanese macaques

Alliance formations in a troop of free-ranging Japanese macaques, which had been provisioned 16 months before the present study was begun, were observed at the feeding ground for about 300 hr from April 1973 to March 1974. The patterns of alliance formations and their roles were described. The leader male had a quite unique role in his alliance formations; he allied much frequently with the aggressees and attacked the aggressors. Besides, the leader male allied more frequently with babies, yearlings, 2-year-old animals, and adult females, while he frequently attacked the 3- and 4-year-old animals and adult males. The animals who belonged to the same matrilineal group always allied with one another. Except the leader male, the troop members rather preferred to ally, except in those cases where the former diads involved their matrilineal group members, with the first aggressors. Networks of such alliance formations in relation with the social organization of Japanese macaques are discussed.     

Puberty in male Japanese macaques (Macaca fuscata): Social and sexual behavior in a confined troop

The social and sexual behaviors of four groups of males (4, 5, 9, and 10 years old) were compared throughout one complete mating season in a confined troop of Japanese macaques (Macaca fuscata). The aim of this research was to document social behavior changes that occurred during adolescence and to relate them to changes in sexual behavior that occurred at puberty. The 4-year-old males all mounted females and ejaculated but they had significantly fewer ejaculations and female partners than did the older males. The 4-year-old males also showed a pattern of delayed development in tail carriage and courtship, and they played more frequently than the older males. There were no significant differences in the frequency of aggression among the groups, but both 4-year-old and 5-year-old males were displaced by adult males and females more frequently than were the older males. We concluded that the development of adult patterns of social behavior in this genus is not climactic, but occurs slowly one to two years after physiological puberty has been reached.     

Seasonality of adult male Japanese macaques (Macaca fuscata): androgens and behavior in a confined troop

Seasonal variations in levels of serum testosterone, dihydrotestosterone (DHT), reproductive behavior, and social behavior were investigated in 12 adult males (5 to 20+ years of age) of the Oregon troop of Japanese macaques (Macaca fuscata). Blood samples were collected at 2- to 4-month intervals, and behaviors were monitored twice weekly over a 15-month period. Significant seasonal variations in levels of testosterone and DHT, and in frequencies of mount series, ejaculations, number of female partners, displays, courtship, and aggression were observed. Seasonal variations in reproductive and social behaviors did not correlate with seasonal variations in androgen levels because seasonal increases in these behaviors followed seasonal increases in the androgens with a 1- to 2-month delay. However, significant correlations between increased androgen levels and the onset of mating activity occur when mean monthly frequencies of mount series are shifted 1 to 2 months earlier to coincide with the rise in serum androgen levels. The frequency of adult male play and male-male mounting increased significantly when androgen levels were low. We suggest that photoperiod changes may function as a proximate cue in male Japanese macaques which induces a state of biological readiness for mating, and the behavioral consequences (i.e., mating) are then dependent upon the presence of receptive females.     

Responses of a transplanted troop of Japanese macaques (Macaca fuscata) to bobcat (Lynx rufus) predation

A series of encounters between a transplanted troop of Japanese monkeys (Macaca fuscata) and one or more bobcats (Lynx rufus) is described. One incident of predation was observed and four additional cases assumed. Reactions of identified individuals and groups of monkeys as well as general troop reactions are noted. The effects of breeding season behavior, troop size, differences in mother care, behavior of the bobcat, and the structure of the south Texas environment are explored. After the observed predation incident, intervention by the researchers affected the behavior of the monkeys and the bobcat, and reduced encounters.     

Retardation of bone development in the Koshima troop of Japanese macaques

Retardation of bone development was observed in the Koshima troop of free ranging Japanese macaques. In the control group, epiphyseal unions of appendicular long bones generally started to close at about 4 yrs of age and were completed at about 8 or 9 yrs of age. Limb bone unions of the Koshima troop, however, started to close at about 9 yrs of age and completely closed at about 15 yrs of age. In the epiphyseal unions of trunk and girdle bones, the Koshima troop again showed a retardation of closure compared with the control group. Until long bones reached their full length, that is, until about 15 yrs of age, their size was small in the Koshima troop compared with the control group, though the sample size of the Koshima troop was small. After 15 yrs of age, however, many osteometrical measurements of the Koshima troop were nearly the same as controls. A prolonged growing duration compensated for the slow growth and allowed them to become as large as controls. This prolongation may be an adaptation in response to small size during the developmental period. In some parts of the body, however, Koshima macaques failed to reach the adult size of controls. Males were less likely than females to reach full size. Causes of the retardation and small size in the Koshima troop are discussed, but they remain open to further studies.     

The social structure of the Oregon troop of Japanese macaques

Intensive observations were made of a troop ofM. fuscata which was kept in a large outdoor corral at the Oregon Regional Primate Research Center during the summer and fall of 1967. The intent of the observations was to determine whether the troop's normal patterns of social behavior and social structure seemed to be affected by confinement in the corral. Substantial deviations were noted between the spatial structure of the Oregon troop and the central-peripheral structure typical of free-ranging troops in Japan. There was also some indication of heightened aggressiveness within the corral but other aspects of social behavior seemed unaltered.     

Supra-annual variation in the influence of Myrica rubra fruit on the behavior of a troop of Japanese macaques in Yakushima

Observations were made on a well-habituated natural troop of Japanese macaques (Macaca fuscata yakui), living in warm-temperate, lowland forest in Yakushima. Between mid-May and the end of June the macaques feed on the fruit of the evergreen tree Myrica rubra (Myricaceae). The fruit of this species are abundant in some years and scarce in others. Data were compared for two heavy-fruiting years (1988 and 1990) and one poor-fruiting year (1991) to examine the influence of fruit availability on patterns of foraging, ranging, and the frequency of inter-troop encounters. In both heavy-fruiting years M. rubra fruit accounted for a maximum of over 70% of foraging time, compared with a maximum of <5% in the poor-fruiting year. Heavy fruiting was also associated with a marked decrease in the overall time spent foraging. In early May of all three years troop movements were largely confined to northern parts of the home range. By early June of both heavy-fruiting years ranging had shifted to the south-west, and included an area with a high concentration of M. rubra trees. This area was rarely visited at other times, and was not visited during the study period in the poor-fruiting year. The overlap in range-use between the two heavy-fruiting years was significantly greater than that between the heavy-fruiting years and the poor-fruiting year. Heavy fruiting was also associated with an increase in the frequency of inter-troop encounters. © 1995 Wiley-Liss, Inc.     

Agonistic behavior and neurochemistry in grouped Japanese quail

Aggressive behavior and whole brain neurochemistry were measured in stable and unstable pairs of male Coturnix coturnix japonica. Aggressive pecking peaked on day 5 of the daily regrouping regime and returned to a basal level on day 14. Aggressive behavior was associated with increased brain norepinephrine (NE), dopamine (DA), and acetylcholinesterase (AChE) in unstable pairs. Habituation (12-15 days) and DA response to daily regrouping and inanition were inversely related in unstable and stable pairs respectively. Normal whole brain NE increases were attenuated in unstable pairs.     

Comparative study of grooming relationships among wild Japanese macaques in Kinkazan A troop and Yakushima M troop

The influences of socionomic sex ratio (SSR; adult males/adult female) and troop size upon male-male, female-female, and male-female grooming relationships were examined and compared between two wild Japanese macaque troops (Kinkazan A and Yakushima M troops) in Japan. The Yakushima M troop was smaller and had a higher-SSR than the Kinkazan A troop. Between the troops, (1) the male-male grooming frequency and number of partners were greater in the Yakushima M troop than in the Kinkazan A troop; (2) the female-female grooming frequency and number of partners were not different; and (3) the male-female grooming frequency and number of partners were not different. Based on these features, the patterns of female-female and male-female grooming relationships appear to be independent of SSR and troop size variations. In contrast, male-male grooming relationships are influenced by both factors, especially SSR. Frequent grooming interactions among males may be useful for the continued coexistence of relatively many males especially in a higher-SSR troop.     

Sex differences in mortality of Japanese macaques: Twenty-one years of data from the Arashiyama West population

Theorists argue that mortality in male mammals should be higher than that of females, and many studies of primates followed across the life course have found this to be the case. This study examines mortality patterns in the rapidly expanding Arashiyama West (Texas) population of Japanese macaques (Macaca fuscata) and finds that males have a significantly lower median survival age (12.2 years) in comparison to females (20.5 years). Males and females are born in equal proportions, but by adulthood there are 2–5 females to every male. Males are at higher risk of falling victim to infectious diseases and human-related causes of death, and they are more likely to “disappear” from the population, which is inferred to result largely from emigration. There are no significant sex differences in the risks of dying from predation, non-infectious illnesses, neonatal defect, or social stress. Males become more susceptible to mortality than females once they reach sexual maturity, and they remain at greater risk than females until their old age. There is no evidence that one sex or the other is at greater risk of dying as infants, or as juveniles. Comparing males of different age classes, adolescent and adult males are more likely to die and to disappear than are juvenile males. These findings support the “high-risk, high-gain” hypothesis that males are mainly lost to the population because of their risk-taking behaviors after sexual maturity, rather than the “fragile male” hypothesis that males are more vulnerable to mortality during the period of growth and development. Am J Phys Anthropol 102:161–175, 1997 © 1997 Wiley-Liss, Inc.