Can you imagine, opening your sliding doors to step outside and see a wolf?
How about a mountain lion? I saw some pix from a friend in Colorado ...she has a Maine coon cat that is kept indoors. It was sitting by a door when a baby cougar came up to the door. The little cat wasn't afraid and stood its ground until the cougar walked away and rejoined her mother who was standing a few feet away.
Gotta love those little guys who stand their ground.
