Where do I find cool feathers?

Hi! New to Adelaide (and oz in general). I know it seems like a silly question, but I'm looking for colourful feathers to garnish my boyfriend's hat, and after a few weeks of looking around parks that have interesting birds, all I can find on the ground is from magpies. It's not nothing, but the bouquet is getting quite dull.

Do you guys just pick up the cool feathers with extreme efficiency? Should I account for the wind blowing them further away?