Clownfish attacking Hawaiian feather duster

I have a 47 gal reef tank with only 2 fish; 1 true percula clown and one ocellaris clown. The two fish were introduced a week apart both at the same approximate size. They've been in the tank 3 months now and have bonded. They swim everywhere together and sleep together at the top of the tank near the HOB filter. I also have a large Hawaiian feather duster worm that has been in the tank for nearly the same amount of time. The worm lives at the bottom of the tank at the base of some rocks. The clowns have never paid any attention to the worm until the last few days. The true perc has begun bullying the worm biting at the crown any time it comes out and even biting at the tube when it is retracted. I think the problem is that the clown has decided it wants to claim the cave-like area formed by the rocks where the feather duster is attached. The problem is he is attached. He has attached his tube onto the base of the rocks. Is there anyway to remove/relocate the feather duster without hurting it so that the clown will leave him alone? Any other thoughts on why the fish might be doing this or what I can do to stop it?