Cockatoos are large and in-charge birds, and if you don't give them what they want, they won't hesitate to let you know about it. That can come off as anger, but sometimes, he's just being misunderstood. Read the signs, and you can give him what he needs to calm down.
Fending Off Intruders
Cockatoos are territorial birds, especially the males. When they get the impression that their space is being invaded, like when strangers come to visit or an unfamiliar hand enters their cages, they can respond aggressively. Sometimes this presents as a lunge or a bite, but out in the open, your cockatoo actually may try to drive away a perceived intruder by chasing him around. It's not that he doesn't like people, just that he feels threatened by someone he doesn't know.
Boredom and Activity
A cockatoo needs mental and physical stimulation to keep from getting bored. They have very active minds and can be prone to mood swings, so leaving one to his own devices without anything to entertain him can lead to frustration and irritability. A happy cockatoo gets plenty of attention, has toys to play with and always has something he can wrap his beak around for some good old fashioned chewing.
Getting a Response
These birds may display angry or aggressive behavior as a way of getting your attention, similar to a misbehaving child throwing a tantrum. Lunging, biting or chasing behavior is entertaining and rewarding for a bored and attention-deprived cockatoo, because he gets the attention and stimulation he's seeking. When this is the case, the bigger the reaction he gets from you and/or his target, the more rewarding he finds the behavior.
Avoiding Aggression
Because there are things that trigger and encourage angry behavior, you must address the problem in two ways. First, identify what his triggers are and address them. He may act out only when strangers come over, for example, or when you haven't played with him for a certain amount of time. Second, on the occasions when he does act aggressively, remain calm and establish a simple protocol for punishment. He may be looking for a dramatic reaction, so don't indulge him. Instead, isolate him in a "time out" for a few minutes, then try to interact with him again.
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Writer Bio
Tom Ryan is a freelance writer, editor and English tutor. He graduated from the University of Pittsburgh with a degree in English writing, and has also worked as an arts and entertainment reporter with "The Pitt News" and a public relations and advertising copywriter with the Carnegie Library of Pittsburgh.