Great Gray Owl can consume several voles per day, to do that they have a great ability to hear and locate the voles in thick grass and in the winter under the cover of snow. The facial disc helps the owl direct sounds to its ears. They have asymmetrical ear openings, the left ear opening is higher than the right ear opening. Which enables the owl more accurately decide where the prey is before attempting to ponce on it. If that was not amazing enough, it has been reported that one Great Gray Owl broke through the snow crust that could hold a 170 pound human. All that work for a tasty vole.