Here's the story about an MIT graduate student who spent an entire summer going to the Harvard football field every day wearing a black and white striped shirt. Every day, he would walk out on the field, blow a whistle, walk up and down the field for ten or fifteen minutes throwing birdseed all over the field and and then he would leave. Of course, use of the field was reserved only for actual games and it was not used for practices.
At the end of the summer, when it came time for the first Harvard home football game, the referee walked onto the field and blew his whistle. The result was an immediate onslaught from all kinds of birds anticipating their birdseed. The game was delayed for a half hour while officials and groundskeepers tried to get the birds off the field.
The student wrote his graduate thesis on his Pavlov birds, and was awarded his advanced degree.