Golden Snub-nosed Monkey - Behavior

Behavior

The golden snub-nosed monkey is found in groups ranging in size from 5-10 individuals to bands of about 600. The social organization of this species can be quite complex. The one-male-units (OMUs) are the basic social unit within groups of golden snub-nosed monkeys with many of the OMUs forming a bigger group. These multi-tier societies consist of several OMUs that include one adult male plus a number of adult females and their offspring. Some observers have even come to conclude that these large foraging groups are multi-male and multi-female societies.

The male may stay solitary, often remaining away from the rest of the group members as they rest. Adult females tend to socialize more with one another than with other males or juveniles. Group members remain close to one another, interactions between different OMUs often result in confrontations. Females of the golden snub-nosed monkey are usually observed to form several close associations with other females. However in conflicts against other units in the surrounding site, both males and females support each other, while also protecting their young (usually observed at a distance by putting the young in the center of the pack).

Protecting the young is a group effort. Mothers often have helpers assisting them with the care of their young. When faced with danger from a predator such as the Northern Goshawk (Accipiter gentilis), the young are placed at the center of the group while the stronger adult males go to the scene of the alarm. The rest of the day, the members of the group remain closer to one another with the young protected at the center.

There is little information available on the sleeping cluster patterns of the Sichuan snub-nosed monkeys. However, in a detailed observation of the free-ranging band in the Qinling Mountains in central China, results have suggested that winter night activity of Rhinopithecus Roxellana is a compromise between antipredator and thermoregulatory strategies and an adaptation to ecological conditions of their temperate habitat. Keeping warm is critical for survival in freezing temperatures, but their thick coats can provide this warmth as well as sleeping in these clusters. Monkeys often sleep in the lower stratum of the tree canopy, avoiding the upper canopy where it is cold and windy. They form larger sleeping clusters at night than in the daytime. The most common types of night-sleeping clusters were adult females and their young, followed by adult females with other adult females. Adult males are usually observed sleeping by themselves or on the lookout for predators or dangers.

There are several hypotheses to explain the formation of sleeping clusters, the most important one being a thermoregulatory process. The thermoregulatory hypothesis suggests that a primary function of sleeping in clusters is the conservation of heat during cold temperatures. Along with thermoregulation, safety from predators is an important principle underlying the formation of sleeping clusters in primates. This antipredation hypothesis suggest that increased cohesion and large sleeping congregations might facilitate predator detection and enhance group defense.