Artificial barriers, such as nest boxes and metal collars, are sometimes used, with variable success, to exclude predators and/or competitors from tree nests of vulnerable bird species. This paper describes the observed response of captive stoats (Mustela erminea) to a nest box design and an aluminium sheet collar used to protect kaka (Nestor meridionalis) nest cavities. The nest box, a prototype for kaka, was manufactured from PVC pipe. Initial trials failed to exclude stoats until an overhanging roof was added. All subsequent trials successfully prevented access by stoats.
Food of the North Island kaka (Nestor meridionalis septentrionalis) on Kapiti Island was identified while quantifying the foraging activity of nine radio-tagged birds from March 1991 to January 1992. Additional food types were identified by opportunistic observation of feeding birds and qualitative examination of nestling faeces. A diverse range of food was taken, including wood-boring invertebrates, scale insects, seeds, nectar or pollen, fruits, and sap.