International Journal of Comparative Psychology

Object use by cetaceans is associated with complex cognitive processes, social relations, play and tool use. A comparative approach of how cetacean species use objects will increase our understanding of how this behavior evolved. This study reports on observations of object use by a small group of wild, provisioned Australian humpback dolphins ( Sousa sahulensis ) in Tin Can Bay, Australia. Data were collated from attendance records, interviews and photographs revealing 23 separate occasions of object use over seven years. A variety of objects, biological and artificial were used by male dolphins during social and play interactions often directed at people. Comparable interactions have occurred in another provisioning program suggesting the behavior may be unique to these situations. The behavior observed in the current study also indicates variations of object use within the species, as objects were not associated with foraging as has been reported in the literature.