From John Irving's The Cider House Rules:

...And the trembling mice beneath the floor of the cider house stopped in their tracks between the cider house walls to listen to the lovers. The mice knew there was the owl to worry about, and the fox. But what animal was this whose sound was petrifying them? The owl does not hoot when it hunts, and the fox does not bark when it pounces. But what is this new animal? wondered the cider house mice- what new beast has charged and disturbed the air?
And is it safe?