Selection of the Young Coconut Mesocarp by the Sulawesi Babirusa (Babyrousa celebensis)

Abstract. The feeding behaviours of the Sulawesi babirusa (Babyrousa celebensis) in terms of its preference to eat the mesocarp, or husk, of immature coconuts (Cocos nucifera) and the feeding marks on leftover coconuts were observed. Additionally, to explore the physicochemical factors behind this preference, a comparative study was conducted on the basal and apical parts of the coconut mesocarp. The breaking load, macronutrient content, and volatile compounds were examined. The findings were as follows: 1) Babirusas always sniffed the cut surface of the coconut before eating. They then scooped out the basal part of the mesocarp where the fibres are more visibly scarce with their mandibular incisors and ate more than 7.6 times the surface area at this end than at the apical end. 2) The preferred basal part of the immature mesocarp had a lower breaking load. 3) The gas chromatography-mass spectrophotometry (GC-MS) chromatogram of the basal sample showed larger peak areas for 2-methylbutanal and 3-methylbutanal. In conclusion, the babirusa preferred the basal part of the immature coconut mesocarp, and the preferred basal part had distinctive features in terms of hardness and volatile profile, which is probably characterised by the presence of 2-methylbutanal and 3-methylbutanal.