Hard to tell. Pearling (the marking on the wings) usually suggest female but its my understanding that male pearl pieds don't always lose all of their pearling once they mature. It's wings are hanging real low though, is it okay?
2 umbrella Cockatoos One male named Cooper and female named Baby 1 Little Corella male named Frankie and have 5 Cockatiels three named Male named Pepper, Fiesco for the female and female named Wylie.
At almost a year old my male still has much of his wing pearls, so it could be either! A DNA test (IQ Bird testing does them for $13) will determine gender for sure.