A flock of Dark-eyed Juncos discover that they like the suet put up for the Woodpeckers. When Juncos get aggressive, they spread their tails to show their white feathers. Bit of that going on here. I've decided that the big reason they travel in flocks is so they don't have to go far to find someone to argue with. If you turn the sound up, you can hear the chittering noises they make. You can also hear the Dragon thumping around in the kitchen, probably breathing on dinner.