Study of environmental and social influence on playing behaviours in gorillas.
Date:2008/03/05 - 2008/03/31
I conducted behavioral study, especially playing behaviors in captive western lowland gorillas kept by the Howletts and Port Lympne Wild Animal Park in UK.
The Howletts and Port Lympne Wild Animal Park is keeping four family gorilla groups in Howletts section and one family and two bachelor groups in Port Lympne section.
I observed the family group in Port Lympne (Djala group) including two babies, five juvenile, seven adult females and one silverback male.
The Djala group uses the inside room and outside enclosures (a garden area and a huge mesh cage).
Playing materials and spaces differed between the babies and the juveniles.
Babies tended to move on mesh walls and ceiling for a long duration.
Duration of social play was longer in the juveniles than the babies.
Individual difference of frequency of social play was observed in the babies (1 year-5 months old and 1 year-7 months old).
Increasing the number of observation subjects and observation duration is necessary to analyze age and sex differences of playing behaviors.