[hugochavez]

I've had my cockatiel for about three months now. I found him outside and at first he would not let anyone touch him without attacking. Now he perches on hands and shoulders without problems and when he is in a good mood will let you scratch his head forever with no problems. Sometimes though he is still so aggressive for no reason and will bite randomly. My girlfriend loves him but still is upset that he is bad sometimes and bites. Ive decided to really try and start training him with food treats and verbal commands now to try and make him a fully tamed bird. I was wondering though if i should get his wings clipped still, and if i do, how long will he be angry after getting them clipped?