Well when Wife and I hit the road full time some years ago we brought along our cats. Alex and Amber. now Alex is the original "Scardy cat" but Amber was more ...er... adventurous (If you heard a strange noise he'd run to hide, she to investigate)... Alas. Amber has crossed the bridge, but Alex is still around and purring.
Barking dogs.. Very very rarely will I hear dogs barking when I'm inside.. and Alex does not go outside.. I mean if I leave the door open he may go as far as the top step and look at me like "Why did you leave the door open" but that's as far.. Oh he has, by accident, gotten out (Fell out a window he did) but when we opened the door.. there he was. ON THE STEP wanting IN.
There have been a few campers who had a dog named "Sir Barks Alot" but park management has a tendency to tell them "Good by and don't return with Barker".