I've just put the Christmas decorations up. First time our parrot has seen them. When they were on he was very noisy.
Are they distressing him or is he excited?
Each bird reacts differently to 'changes' in the house. Some may get excited and noisy, while others may suddenly become very quiet and even withdrawn.
I'd say watch the body language, make sure he still eats and plays as usual, and I'm sure he'll get used to the lights in no time at all.
Probably excited. Kiwi goes nuts over the Christmas tree when it first goes up, and could give a hoot less about it by Christmas.
Is your bird just making noise or actually displaying aggressive body language? Making noise, he's probably just excited and intrigued, possibly really likes it. If he's behaving in an aggressive manner, there may be an adjustment to the tree being in his line of sight. Even if that is the case, don't feel you need to move him or the tree. He WILL get use to it and come to realize it's not a threat.