Kea, Nestor notabilis, produce dynamic relationships between objects in a second-order tool use task

Studies on advanced forms of tool use in birds have mainly been concentrated on corvids. In this study, captive kea, a neophilic New Zealand parrot species, produced different orders of spatial object relationships in a tube-lifting/object-inserting paradigm. Hence, we found that kea, which are neither natural tool users nor nest builders, could readily solve a second-order tool use task. They also learned to produce highly complicated means–means–end sequences in a short period of time.