On The Wing is a movie about the "famous" swifts that gather in Portland, OR in the fall. According to the website, each autumn, thousands of Vaux's swifts gather to roost in a chimney of an elementary school in Portland. The thousands of swifts apparently attract a devoted following of thousands of watchers. The website describes it as a " cult phenomenon over the past 15 years and a shining example of people choosing to coexist with nature rather than smoking it out."
Here's a trailer: