[Dog Tracks]

My rat terrier does that all the time - outside. She leaps/lunges on hidden prey (vole under fallen tall grass, mice under the snow, etc).

The only time she did it indoors was at a friends apartment. Lunging into the baseboard of the wall. I'm sure she sensed a mouse behind the wall. She'd have torn through the drywall if I hadn't leashed her and kept her near us.