Bloo Dog wrote:
Common honey bees are stunned by flash. Years ago I photographed some bees doing what they do among the flowers and i used a ring flash. I noticed that most of the bees I photographed suddenly dropped from sight. I looked to the ground to see them crawling around. After a minute or so they seemed to be okay.
I can't speak for all dogs, but Dalmations can be spurred to rage by studio flash. Before i abandoned portraiture for the much safer haven of wedding photography, I took a series of shots of a woman's dog.
No, wait. I took one shot of the dog and then a series of shots of the ceiling as the dog leaped from the stage and went for my collar.
After that, I shot ONE dog and it was an English Mastiff-- it was part of a bridal portrait (Please DON'T ask. Nothing weird. The dog was just there. And it drooled).To get an idea of what one of these animals looks like think of a dog with the body mass of a horse and the temperament of a clam until it decides to become affectionate. This crazy dog allowed about a half dozen shots before it decided that my camera lens might taste good. It went for the camera and LICKED the lens. There was dog spit everywhere. Then he went after me and slobbered all over my shirt.
So there are three possibilities: Stun, Attack, and Slobber.
I've always heard it expressed as "rapidly flashing", but flashing lights can trigger an epilepsy reaction in some people. I have no idea whether or not dogs suffer from epilepsy, and I have no recognized medical education, so don't go quoting me at parties. 
Jim