I was on the arboretum bird walk this month and watched a couple of flickers performing their display that is used for courtship and territorial defense. In early spring or summer during courtship, they will face off in this display usually while a prospective mate watches. Since it is October, I imagine these two were engaged in territorial defense. The Cornell Lab’s All About Birds describes this display thus: “Two birds face each other on a branch, bills pointed upward, and bob their heads in time while drawing a loop or figure-eight pattern in the air, often giving rhythmic wicka calls at the same time.” They would also fan their tail feathers. The flicker on the right seemed slightly bigger and slowly backed the other one out to the end of the branch. The smaller flicker eventually flew around its rival to a nearby vertical limb. The other flicker followed and they continued their dance circling the limb.
Resources
Northern Flicker Life History, All About Birds, Cornell Lab of Ornithology. https://www.allaboutbirds.org/guide/Northern_Flicker/lifehistory. Accessed 25 Oct. 2023.