Keira does a lot too. Only around dogs though. Or cats. Or other animals. Never for noises or humans. I think with her and animals it's a minor insecurity thing (with other dogs) and excitement/prey drive (cats and other animals). She's always raised her hackles easily, even as a young puppy. It's never gone away. The general public automatically assumes it's aggression, but it's definitely not. Oh, and she raises them when she's cold too.