The many respondents are correct. The male is chasing the female. It is quite a lot of fun to watch. I am hoping to locate the nest. It is possibly along the ridge where the large white pines are behind the houses on the east side of Rivermount in the new north end. This is also directly across from the gardens at the Ethan Allen Homestead above Route 127. - The downside? No birds at the feeders for quite some time now.