- This is always a top possibility. This includes any sort of wildlife that could be on, in or near your home.
Some may be on the roof, others (sorry!) in the walls and some right outside in a tree or other area close the house. Squirrels, chipmunk, mice, raccoon, birds, bats.. these are all reasons that a dog will act oddly, either in a defensive positioning or trying to alert you.
High pitched noises
- Far out of your ability to hear it, dogs can pick up on such sounds as alarms and sirens from quite a distance. This includes home and car alarms and emergency vehicles.
Radio & other frequencies
- There are anecdotal reports of dogs being irritated by all sorts of things; this includes cable wires, neon lights, baby monitors, intercom systems and security systems.
- What may seem like background noise that you've learned to ignore or sounds that simply do not register to your human ears, can make a dog stand on guard, act wary or try to alert you.
This includes everything from car doors slamming, the beep of a car being locked, children playing and of course, other dogs barking or howling.