Feeding activity of threatened black cockatoos in mine-site rehabilitation in the jarrah forest of south-western Australia

Land clearing threatens three black cockatoo species (forest red-tailed black cockatoo, (Calyptorhynchus banksii naso), Carnaby’s cockatoo (Calyptorhynchus latirostris), and Baudin’s cockatoo (Calyptorhynchus baudinii) endemic to south-western Australia, so revegetation is important to their recovery. Over three years we studied cockatoo activity in 7–14-year-old mine-site rehabilitation in the region’s jarrah (Eucalyptus marginata)–marri (Corymbia calophylla) forest to give the most detailed description to date of the use of rehabilitation by the birds. Pits varied floristically and structurally (despite similar rehabilitation prescriptions), but interior and exterior plots (100 m2) were similar within pits. Using feeding traces (e.g. chewed husks), and behavioural observations we confirmed feeding within eight years of revegetation. Plots containing feeding trace were similar to plots without, so factors determining black cockatoo feeding may not be apparent at small scales. Returning food resources reflected vegetation succession, with regenerating marri and fast-maturing proteaceous species providing most food. Carnaby’s cockatoo ate Banksia and Hakea seeds and Baudin’s cockatoo and the forest red-tailed black cockatoo consumed marri seeds. Banksia squarrosa, Hakea undulata, H. prostrata and marri were common foods in all years. Revegetation efforts elsewhere should consider these species, within the constraints of rehabilitation protocols addressing multiple aims.