Late last year we updated our community on the successes witnessed by the Wheatbelt NRM Healthy Environments team traversing the Wheatbelt for insights on the nesting behaviour of the black cockatoo.
Our programs in November and December surveying the black cockatoo habitat for nesting hollows provided even more valuable information that we are excited to share with you.
The information regarding cockatoo breeding in the Wheatbelt is limited and we’re learning more as we go. During our most recent surveys we have found cockatoos nesting in hollows far smaller than previously observed.
Typically, the bird’s breeding habitat is considered to be stands of mature, hollow-bearing trees such as the Wheatbelt species of salmon gum, wandoo and marri on the western edge.
For these trees to form adequate nesting hollows they are thought to be mostly over 150 years old with a diameter at breast height (DBH) of over 50cm to allow the female to enter the hollow and sit on the eggs.
However, the following footage taken by our survey team shows a female Carnaby nesting in a dead stem with a DBH of less than 30cm. While conducting a “tap and flush” the team heard the female climbing over 3m up the trunk to get to the hollow entrance!
According to Wheatbelt NRM project delivery officer Alex Griffiths, this discovery could expand the range of hollows that could host and be monitored for nesting activity.
“This could be an indication that the hollow itself may not be the determining factor in whether the pair will nest in an area, and may be more heavily influenced by the access to food and water to successfully raise chicks to fledglings,” Ms Griffiths said.
“Therefore we need to consider a multitude of motivating factors that may influence breeding area selection – the more we can observe the more we hope to understand the Wheatbelt requirements for the black-cockatoo and how each of these may be weighted.”
While most black-cockatoos will be leaving the Wheatbelt as their breeding season comes to an end, we are still getting reports of sightings.
Any sightings we receive from the community are extremely valuable as each reports helps build a picture of their behaviours and presence in the region.
Your reports are improving the quality and quantity of Wheatbelt-specific black-cockatoo data, so please keep sending us your survey information.
If you think Carnaby's were nesting in your area over the past few months, please let us know as that will help feed into our monitoring for this year’s breeding season.
This project is supported through funding from the Australian Government’s National Landcare Program.