Banging the brakes on

This great tit was heading towards one of the feeders but he suddenly screeched to a halt and then flew off again. There must have been something else already on the feeder but I couldn't see what as the wisteria is covering it at the moment.
This is just after the brakes were applied. As you can see, his face in focus, but his body and wings were still travelling. 
We didn't get to eat our dinner until about 9:30 this evening, which is late even for us. It's now just gone 10 and I'm off to bed - with a full tummy which I know you shouldn't do.