Douc Langurs (Pygathrix spp.) Fact Sheet: Behavior & Ecology

• Diurnal
• Arboreal; never seen on the ground in the wild.
• In the wild, colobids spend at least 50% of the day feeding. In managed care they are offered food several times a day.
• There is considerable play within a family group. Animals of the same age tend to play together
• Social grooming in the wild occurs most frequently in the afternoon, before napping. Episodes last a few seconds to 1 hour
• Sleep in elevated positions; pairs sleep together and females sleep with their offspring

• Group size is variable depending on habitat and human disturbance. Sightings range from 3-50. Solitary animals have also been observed
• Groups are overwhelmingly multi-male and multi-female with a sex ratio of 2.5 females to each male.
• Both male and female dispersal occurs. Females probably leave as a result of female- female aggression. Juvenile males disperse and join all-male or non-reproductive groups of both sexes.
• Female association attributed to kinship and spatial distribution of preferred food resources. (Unripe Fruit/seeds)
• Colobine aggression increases with group size
• Alloparental care as with most Asian colobine species (gives mother time to forage, ensures social integration of new infants and improved parenting skills)
• Allogrooming somewhat more frequent than solitary auto grooming. Seen frequently among females. Males invited grooming but infrequently reciprocated.

Displays / Visual signals

• Male observed to "threaten" intruders by brachiating back and forth. May leap toward an intruder. Then quickly retreat
• Rapid jumping from branch to branch combined with hand slapping
• Panic diarrhea common
• Threatening behavior toward others by males after the birth of a new born: flattening ears against the head, stretching the neck forward and making threatening growls

Vocalizations

• Make few vocalizations. Most are very soft.
• Threat elicits a loud call or bark
• Low pitched growl given as a threat to others
• Loss of a long-time mate elicited several days of mournful howling in one male

Territory

• Group ranges overlap considerably
• Ability to exploit mature foliage which is available year round may explain why colobines appear to be less aggressive than non-colobines

Play

• Considerable play in a family group. During first few months, infants engage in hopping, running, jumping and climbing.
• Usually directed at social partner or animal of same age
• To initiate play an animal throws back its head and opens its mouth

• Dominance hierarchies among managed care groups
• Female-female allogrooming
• Intragroup relationships in wild poorly documented presumably because of poor visibility of arboreal species
• Ethogram: available in Abbot et al. (1997-2000), Douc langur project, p. 10: Table 4

• Quadrupedal movement though established arboreal pathways
• Little brachiation or bipedal locomotion
• Horizontal jumps begin like a dive, arms held above the head and legs thrust forward. Able to Land on rear feet 5-6 m away 
• Traveling
  • Travel through the rainforest in single file.
  • Movement less organized in dense areas 

Image credit: © San Diego Zoo Wildlife Alliance. All rights reserved.

Lippold (1977)
Lippold (1998)
Whitehead & Jolly (2000)