Food preparation behaviour of babirusa (Babyrousa celebensis)

Food preparation behaviour of sand-contaminated food articles by two zoo-based Sulawesi babirusa (Babyrousa celebensis) was observed and recorded as video imaging data at Bali Zoo, Indonesia during an observation period of six days in July 2012. In earlier preliminary studies of four animals, comprising two mother-infant pairs, three animals held pieces of cut sweet potatoes in the mouth, carried them to a neighbouring water trough, dropped or dipped them in the water, and then began eating. This behaviour was repeated at almost every feeding time. To characterise and elucidate this food preparation behaviour further, and within the management constraints of a zoo environment, experiments with various test feeds were designed; the dipping of food articles into water was video-recorded on 37 occasions. This behaviour by the babirusa was related to (1) deliberate sandcontamination of the surface of the food; (2) deliberate provision of large-sized pieces of food, and (3) the supply of large amounts of food at one time. The distance of the water source from the food seemed to play a role in the expression of the ‘food washing’ behaviour, with short (1.5 m) distances preferred over longer (6 m) distances. The frequency of this type of babirusa food preparation behaviour was higher during the second half of a feeding period