I have a roadrunner couple that has a territory around my house and down my lane.. I live in the country. One of the roadrunners will bring a small rock up to the house window.. leave it on the ledge and when it feels like it taps on my window the rock. I caught it one day doing it. I came house today and I find three small rocks lined up on my step.. I have a glass door.. I assume that the roadrunner is tapping on the glass because it sees it's reflection.. what do you think.. is this behavior used in the wild?