Usually, it's the weather you're worried about with an outdoor graduation.
I remember a few years ago when parents and students ran for cover under the bleachers at a local graduation. The school had taken a chance on a "chance of rain" and lost that bet!
But you really don't think about wildlife... in particular, birds... causing a disruption.
Well, now they will in Malibu, California... after pelicans pounced on parents (sorry, I love alliteration!) during graduation.
Twitter response tied this to the NBA playoffs, drawing a response from the Pelicans!