Residents are flocking together to survey cockatoos as part of the annual Great Cocky Count on April 3.

Every year volunteers monitor known roost sites to count white-tailed and red-tailed black cockatoos as they come into their evening roosts on a single night just before sunset.

Jarrahdale resident Jan Starr, who has taken part in the count for about four years, said it was important to get a measure of the endangered birds.

“They are very much in danger of disappearing as we clear their feeding grounds and their resting sites,” she said.

“There’s been quite a marked decline but they do vary a lot.

“Quite recently I saw a lot of them at once but I haven’t seen that many for a number of years.”

She said black cockatoos were a beautiful bird and to lose them would be a tragedy.

Over time the statistics collected across the state from the cocky count will provide a snapshot of the population, quantify changes in numbers and assist with conservation.

For more information about the Great Cocky Count or to find out about a roost site call the coordinator on 9387 2251.

You can also get in touch by emailing greatcockycount@birdlife.org.au.