"Then, out of nowhere, a flock of birds flew by the window, extremely fast and incredibly close." (p.165)
There are a couple of picture pages with a flock of flying birds. Like on pages 166, 167, and two pages before the title page.
The issue of flight occurs several times in the novel, normally when Oskar is referring to September 11th and the death of his father. Flight is used to both represent danger(airplanes) and safety(birds.)