The use of waste plastic piping for enrichment devices and cage furniture in primate enclosures at Edinburgh Zoo (1996)

Catlow, G., Nicoll, L.

Abstract

This simple plastic tubing circle can be used as a very flexible piece of cage furniture; it swings freely in the enclosure and can be moved from one area to another easily. ... The level of interest obviously increased when a food item was added to the pipe enrichment device, but even when there was no food in the pipes they were used as swings.