This study is an assessment of the use of mealworm dispensers as environmental enrichment devices for Rodrigues fruit bats (pteropus rodricensis). Captive animals frequently receive easily consumed food at set times and locations, which often minimizes the time they spend searching for and processing food. The mealworm dispensers used in this study provide an unpredictable food source, which allows the link between foraging and feeding to be reinstated. Mealworm dispensers were placed into the Rodrigues fruit bat enclosure at the Jersey Wildlife Preservation Trust and the behaviour of the bats recorded over 14 days. For 7 days the dispensers were empty but, for the remaining 7, 20 mealworms were placed in each dispenser. The number of bats feeding declined with increasing time from initial food presentation in all cases, but the presence of mealworms in the dispensers decreased the rate of decline. In addition, the number of bats active within 20cm of the food in the dishes and on the heater tops increased significantly when mealworms were present. Although the presence of mealworms had no effect on the number of flights made by the group of bats as a whole, both the number of bats on the enclosure floor and the amount of aggression observed in the enclosure decreased when mealworms were present.
Installation of mealworm dispensers meant that the bats found food items as a consequence of their natural exploratory and foraging behaviour, and as such they provided important ingredients for approximating a natural habitat and improving welfare.