This study was conducted as part of the glossy black-cockatoo recovery program and was supported by an Australian Postgraduate Research Award. The small number of movements made by glossy black-cockatoos when foraging on Kangaroo Island reflects the abundance of food trees and may be a strategy to reduce the risk of predation. This shows that breeding birds increased their energy intake without greatly increasing movement between trees. When breeding, the cockatoos spent significantly more time per day foraging, cropped cones in significantly more bouts per tree and harvested significantly more cones per tree than non-breeding birds. This shows that the cockatoos made few movements between drooping sheoaks and within the canopy of the sheoaks when foraging. The cockatoos spent 0.4% of their time flying, foraged in a mean of only five trees per day and harvested cones in no more than five bouts per tree. Non-breeding birds spent only 26% of their time feeding and breeding birds spent only 36% of their time feeding. Glossy black-cockatoos spent a relatively small proportion of their time foraging, suggesting that the food supply was abundant in the habitats used for feeding. The foraging behaviour of non-breeding and breeding cockatoos was also compared to record the strategy they used to collect the additional energy needed to raise young. The time budget of the glossy black-cockatoos and their foraging behaviour was recorded to provide an indication of whether their food supply was likely to be limiting. The endangered Kangaroo Island glossy black-cockatoo ( Calyptorhynchus lathami halmaturinus) relies entirely on the seeds of the drooping sheoak ( Allocasuarina verticillata) for food.
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