Environmental enrichment is an effective method of enhancing the wellbeing of zoo animals. A common approach to enriching a captive animal's environment is to introduce feeding methods which encourage exploratory or manipulative behaviour and which stimulate natural foraging behaviours, thus keeping the animal occupied. Such feeding enrichment may take a variety of forms. In a study at the Jersey Wildlife Preservation Trust two groups of ruffed lemurs Varecia variegata were fed under two different conditions. Both groups shared their enclosures with ring-tailed lemurs Lemur catta, and interspecific and intraspecific aggression was known to occur over food. Food was scattered on/near the ground of the enclosure (baseline), or was suspended in hanging baskets (experimental). This regime was altered on a daily basis over 22 days. Behavioural observations of activity in between feeds and of aggression at feeding times were made. On experimental days, aggression between ruffed and ring-tailed lemurs was significantly lower than baseline. The ruffed lemurs were also more active and spent more time in the trees than on baseline days. Explanations for these effects are suggested.
