Male Brown-headed Cowbirds have been engaging in courtship display in the backyard this week. Interestingly, they seem to display to each other in order to entice females closer. This is sort of like the multiple male displays one sees at a grouse or prairie chicken lek (see my earlier post on this), and serves a dual purpose of stimulating males to perform, while giving females a chance to compare their performances and choose the “best” male to fertilize her eggs.
The sequence of alternating displays begins with first one bird and then the other puffing up, spreading wing and tail feathers and bowing to the other bird while emitting a blackbird-ish, high-pitched call note.
Bird on the right begins the sequence…
Back to neutral, bill up position…
Male on left displaying in bowed head position…
Another male pops in between the two displaying males — will this exhibition be a trio?
I’m not sure if this is a threat display by the left-most male, but it doesn’t continue with the bow, and the middle bird took off quickly. (Females are grayish, with some faint striping on the breast feathers.)
Leaving the two original males to continue their dance…
The short video clip below by Bradley Yee illustrates the sequence of displaying male Brown-headed Cowbirds very well.
Back Yard Biology 
What amazing photos. I’m so glad to have found your blog.
Thanks, Anne. There are 5 years of photos to catch up on, haha 🙂