Feeding enrichment in an opportunistic carnivore: the red fox

In captive carnivores, species-specific behaviour is often restricted by inadequate feeding regimens. Feeding live prey is not feasible in most places and food delivery is often highly predictable in space and time which is considerably different from the situation in the wild. As a result, captive carnivores are often inactive, show little behavioural diversity and are prone to behavioural problems such as stereotypic pacing. Using artificial feeding devices to substitute for natural food resources is a way to address these problems. In a group of four red fox (Vulpes vulpes), we compared a conventional feeding method to four different methods through the use of feeding enrichment that were based on natural foraging strategies of opportunistic carnivores. Feeding enrichments consisted of electronic feeders delivering food unpredictable in time which were successively combined with one of three additional treatments: a self-service food box (allowing control over access to food), manually scattering food (unpredictable in space), and an electronic dispenser delivering food unpredictably both in space and time. The aim of administering feeding enrichment in this study was to stimulate appetitive (food searching) behaviour and to increase time spent feeding. Compared to conventional feeding, diversity of behaviour and overall activity were significantly enhanced in the presence of electronic feeders in all four foxes (EF > CON1=CON2, EF+SF > CON1=CON2, EF+MS > CON1 CON2, EF+ED > CON1=CON2). Behavioural diversity was highest when the foxes had control over access to food (EF+SF), while the manual scattering of food (EF+MS) and the electronic dispenser (EF+ED) enhanced food searching behaviour. These results indicate that in opportunistic carnivores natural foraging and feeding behaviour can be stimulated by simple feeding enrichment strategies, and that foraging behaviour is stimulated most when food delivery is unpredictable both in space a nd time