Artificial nesting hollows for the conservation of Carnaby’s cockatoo Calyptorhynchus latirostris: definitely not a case of erect and forget

Loss of nest hollows in eucalypt woodlands is a major cause of decline for a range of Australian native birds including Carnaby’s cockatoo Calyptorhynchus latirostris. Loss of breeding habitat, plus decay of natural hollows, results in fewer nest sites for this species. Provision of artificial nesting hollows for Carnaby’s cockatoo is a recent part of approved environmental offsets under Western Australian and Australian government environment approvals processes. In this study we examined the continuing utility of natural and artificial nest hollows over time and show that both nest types require repairs on average every 3-4 years. Repairs extend the working life of natural nest hollows and ensure that any artificial nest hollows established for conservation management purposes should continue to fulfil their purpose. We provide data on the costs associated with the supply and deployment of artificial nest hollows, and indicative annual cost per nest hollow for repairs to natural and artificial nest hollows. Our results demonstrate the importance of regular maintenance to ensure hollows remain available for breeding cockatoos. Artificial nest hollows provide a short-term solution to a larger problem of loss of native woodlands, but will only serve that purpose if current and future artificial nest hollows are monitored and repaired on a regular basis, and that adequate funds are provided to ensure that those nest hollows remain serviceable. Provision and maintenance of large numbers of artificial hollows in association with restoration/replanting of woodlands in breeding areas is the only long-term solution to loss of breeding habitat.