Comparing Two Manipulable Objects as Enrichment for Captive Chimpanzefs
This study compared the effectiveness of kraft wrapping paper and rubber toys as enrichment for 22 chimpanzees group-housed in conventional indoor/outdoor runs. Objects were tested separately during 67 hours of data collection using a group scan sampling technique. Paper was used a
mean 27 per cent of the available time, while the Kong Toys™ were used a mean 10 per cent of the available time. The degree of object manipulation and object contact was higher with the paper, but the level of social play and solitary play with the object was not differentially
affected by the two objects. The objects had differing effects on the subjects' levels of grooming, but affiliation, agonism, inactivity and sexual behaviour did not vary according to the object being used. A gender-by-age interaction was found, with immature males exhibiting the highest levels
of solitary play with objects. Object use steadily declined over the first hour of exposure, showing evidence of habituation. Object use when the Kong Toy™ was present declined over the course of the study, but use of the paper remained consistent. Texture, destructibility,
portability, complexity and adaptability may be important in determining the object's value as effective enrichment. The destructible wrapping paper was a more worthwhile enrichment object than the indestructible Kong Toy™ for the captive chimpanzees in this study.