Behavioral responses of free-ranging Japanese macaques (Macaca fuscata) to sudden loud noises.

We opportunistically observed 31 cases of responses to sudden loud noises mainly caused by falling rocks and trees in a free-ranging, provisioned group of Japanese macaques, Macaca fuscata, at Katsuyama, Japan, and analyzed 27 cases for which we successfully recorded their responses. In 88% of the 24 cases in which the highest- or second-highest ranking adult male probably heard the noise, one or both of them vocalized aggressively in response. Other males tended to vocalize when they were far away from the two highest-ranking males (in 5 of 7 cases in which they vocalized).

Daytime spatial relationships in a family group of black rhinoceros Diceros bicornis at the Hiroshima City Asa Zoological Park, Japan.

Although black rhinoceros Diceros bicornis are mostly solitary in the wild, the Hiroshima City Asa Zoological Park (Asa Zoo) has kept a family group together during the daytime, with good reproductive performance over five decades. Management procedures at the zoo include temporary single housing of the mother before and after giving birth, which facilitates maintenance of a compatible family group. We recorded intra-group spatial relationships for 4 years and 4 months, during which time an adult female reared two consecutive calves.

Factors affecting captive female giraffe stress response: Male presence, small enclosure, and low temperature.

To improve animal welfare based on suitable social housing conditions, it is important to understand the factors that trigger high-stress responses. Wild giraffes live in a fission-fusion society and males and females are rarely in the same herd for a long period. The captive condition of belonging to a herd with the same individuals for months or years is uncommon in nature.

Behavioral responses of solicitors after failure to receive grooming in Macaca fuscata.

Grooming is one of the most common cooperative behaviors among several animal species. However, the tactics used to cope with uncooperative partners in grooming interactions remain unclear. Japanese macaques (Macaca fuscata) solicit grooming from partners through postural behaviors, but may not necessarily receive grooming.

Male care in a free-ranging group of Japanese macaques (Macaca fuscata).

Among the Macaca species, adult male Japanese macaques are the least likely to perform male care (i.e., affiliative interactions between adult males and immatures, including holding, carrying, and grooming); however, they perform male care for infants, albeit infrequently.

Professor Masao Kawai, a pioneer and leading scholar in primatology and writer of animal stories for children.

This Editorial is dedicated to Professor Masao Kawai (Fig. 1), who passed away on May 14th, 2021. He served as the sixth Editor-in-Chief of Primates for 15 years (1981-1995).

Triadic grooming among adult females in a free-ranging group of Japanese macaques.

This study aimed to quantitatively describe triadic grooming bouts in a free-ranging group of Japanese macaques (Macaca fuscata). Two types of triadic grooming bouts occurred less frequently and for a shorter duration than dyadic grooming bouts: straight-line type (SL), where individual A grooms B, who then grooms C; and two-to-one type (TO), where individuals X1 and X2 groom Y. TO-type grooming was recorded more often than SL-type grooming.

High but not low tolerance populations of Japanese macaques solve a novel cooperative task.

Currently, it has been revealed that high levels of tolerance facilitate the occurrence of cooperative behavior in animals. This predicts that Japanese macaques (Macaca fuscata) would fail to solve cooperative food-retrieval tasks because of their low level of social tolerance. However, Japanese macaques exhibit regional differences in their levels of tolerance.

Temporal adjustment of short calls according to a partner during vocal turn-taking in Japanese macaques.

Turn-taking is a common feature in human speech, and is also seen in the communication of other primate species. However, evidence of turn-taking in vocal exchanges within a short time frame is still scarce in nonhuman primates. This study investigated whether dynamic adjustment during turn-taking in short calls exists in Japanese macaques We observed exchanges of short calls such as grunts, girneys, and short, low coos during social interactions in a free-ranging group of Japanese macaques.

Vocalizations during post-conflict affiliations from victims toward aggressors based on uncertainty in Japanese macaques.

We investigated the use of vocalizations called "grunts," "girneys," and "coos" accompanied by post-conflict affiliative interaction between former opponents (reconciliation) in Japanese macaques (Macaca fuscata). Although reconciliation functions to repair bonds, such interactions sometimes entail risks of receiving further aggression. Vocalizations can be used at a distance from the former opponent; thus, we predict that vocalizations are used particularly by victims of a conflict, and are frequently used in situations of uncertainty when it is difficult for them to estimate whether the former opponent will resume aggression.

Japanese macaque (Macaca fuscata) mothers huddle with their young offspring instead of adult females for thermoregulation.

It is unclear whom animals select to huddle with for thermoregulation. In this study, we investigated whom Japanese macaque (Macaca fuscata) mothers huddled with-their young offspring or other adult group members-when there is need for thermoregulation. We used a focal-animal sampling method, targeting 17 females at Katsuyama, Okayama Prefecture, Japan.

Emotional states after grooming interactions in Japanese macaques (Macaca fuscata).

In animal societies, the effect of grooming interactions on anxiety reduction is unclear. This study examined the effects of giving and receiving grooming on anxiety reduction in free ranging female Japanese macaques (Macaca fuscata) by measuring rates of self-scratching as an index of anxiety. In this study, the authors used a focal-animal sampling method, targeting 17 females at Katsuyama, Okayama prefecture, Japan.

Daytime mother-calf relationships in reticulated giraffes (Giraffa cameloparadalis reticulate) at the Kyoto City Zoo.

The present study quantitatively assesses the relationships between a reticulated giraffe mother and her first- and second-born calves during the first 22 months of the older calf's and the first 12 months of the younger calf's life at the Kyoto City Zoo, Japan. The mother permitted her calves to suckle at over 70% of their suckling attempts in the first month after their births, and the calves ceased suckling spontaneously in 65 to 70% of the suckling bouts. From the second month on, she showed a clear tendency to reject the calves' suckling attempts and terminated almost all of their suckling bouts, which resulted in approximately 60 sec or less of suckling duration per bout.

Twelve-year proximity relationships in a captive group of western lowland gorillas (Gorilla gorilla gorilla) at the San Diego Wild Animal Park, California, USA.

Proximity data were collected in a captive breeding group of gorillas (Gorilla gorilla gorilla) at the San Diego Wild Animal Park (currently called the San Diego Zoo Safari Park) twice a year (spring and fall periods) for over 12 years, by using a convenient method in which individuals less than 5 m from each animal in the group were recorded by scan sampling, approximately once per hour. Immature females from infancy to young adulthood maintained relatively frequent proximity to both their mothers and the silverback male and spent little time alone (no animals within 10 m), with relatively large individual differences. On the other hand, immature males decreased the time spent near their mothers and the silverback male and increased the time spent alone with increasing age.

Social consequences of disability in a nonhuman primate.

Debates about the likelihood of conspecific care for disabled individuals in ancestral hominins rely on evidence from extant primates, yet little is known about social treatment (positive, neutral or negative) of physically disabled individuals in nonhuman primates. A group of free-ranging Japanese macaques (Macaca fuscata) at the Awajishima Monkey Center (AMC) in Japan presents a unique opportunity to investigate the relationships between physical impairment and social behavior, in the context of congenital limb malformation in adult nonhuman primates. We collected behavioral data on 23 focal animals, taking 30-minute continuous time samples on disabled and nondisabled adult female Japanese macaques during three consecutive birth seasons (May-August 2005, 2006, and 2007).

The effect of solicitations on grooming exchanges among female Japanese macaques at Katsuyama.

In group-living primates, individuals often exchange grooming with not only kin but also non-kin. We investigated the effect of soliciting behaviors on grooming exchanges in a free-ranging Japanese macaque (Macaca fuscata) group at Katsuyama. In this study, we used a focal animal sampling method, targeting 14 females.

Grooming-related feeding motivates macaques to groom and affects grooming reciprocity and episode duration in Japanese macaques (Macaca fuscata).

Allogrooming is considered as an altruistic behavior wherein primates exchange grooming as a tradable commodity for reciprocal grooming or other commodities such as support during aggression and tolerance during co-feeding. First, we report a case of the grooming relationships of the lowest-ranking adult female in a group of Japanese macaques (Macaca fuscata). The female (Lp) had lost a portion of the fur and was groomed by higher-ranking individuals without providing reciprocal grooming or other commodities.