Black cockatoo survey in Western Australia
Friday, May 21, 2010 at 7:20 
Carnaby's black cockatoos roost in tall trees, often pines, high in the landscape and close to water sources as well as taller food trees such as banksias. Image by Delia Anthony
Black cockatoo count reveals vital information
Wildlife managers are learning more about the numbers and distribution of the endangered Carnaby's black cockatoo following the results of a survey of nocturnal roost sites across Perth.
The Great Cocky Count 2010, funded by the State Government's Natural Resource Management program, was coordinated by Western Australia's Department of Environment and Conservation (DEC) and Birds Australia and will provide valuable information for the conservation of the species.
Carnaby's black cockatoo is endemic to Western Australia and is under threat from habitat loss. Each year birds migrate to the Swan Coastal Plain over summer, when they become a highly visible and iconic part of the Perth environment.
The Great Cocky Count
The Great Cocky Count 2010 saw 189 sites visited by 350 volunteers on the evening of April 7 to count cockatoos. Of these sites, 130 were confirmed as active nocturnal roosts, with about 6500 Carnaby's black cockatoos counted in the greater Perth area.
This is consistent with the estimate of between 10,000 and 15,000 birds across the Swan Coastal Plain from Lancelin in the north to Dunsborough in the south, but is below previous estimates of 8000 to 10,000 birds for the greater Perth area.
DEC regional ecologist Geoff Barrett said a survey in 2006 gave a minimum number of black cockatoos at 4500, but this estimate was based on counts at a smaller number of roosts and therefore could not be compared to the 2010 survey.
"The 2006 survey demonstrated the value of nocturnal roost counts and since then we have significantly increased the number of known nocturnal roost sites and refined our methodology. As a result we can now make much more accurate estimates about the numbers of birds in the Perth area," he said.
Dr Barrett said DEC will use the roost information as well as feeding and breeding observations to map habitat used by the Carnaby's black cockatoos, with the aim of protecting key sites for the species.
"Surveys planned for future years will enable DEC to monitor changes in numbers of birds and breeding success from season to season," Dr Barrett said. "There is still a lot to learn about Carnaby's black cockatoos, and these Great Cocky Count surveys are providing valuable information about the behaviour, distribution and general health of the population."
Four further coordinated counts are scheduled this year before most birds return to the Wheatbelt to breed. These are expected to reveal more important information about use of nocturnal roost sites during the non-breeding season.
Dr Barrett said community involvement in the survey was vital in enabling all roost sites to be visited at the same time, providing an accurate estimate of the overall number of birds around Perth.
"DEC and Birds Australia extend their sincere thanks to every one of the 350 volunteers who ventured out just before sunset on April 7 to count the birds as they returned to their roosts for the night," he said.
"The survey really depended on getting a good turnout of volunteers to monitor all known nesting sites, and thanks to the people of Perth who are committed to conserving the Carnaby's black cockatoo, we achieved that."