Hi, I have two questions that I didn't notice in here so far...
1.) Might the area in the picture have been under mottled light, such as from a tree full of leaves? I could almost see the drop moving in and out of the light and producing that sort of image, but the gradual seperation between the dots would mean it would have to be a very precise pattern of mottled light. So, I guess there went that theory.
2.) My second thought, is are you absolutely positive it's a drop of water? You'd be the one to know, but did there happen to be anyone near you when the picture was taken, maybe throwing rocks out at the ice to break it? My thought is possibly a rock or something thrown in a curve up and outward and spinning so that it caused flickering light-flare in the lens as it went.
It would be quite a coincidence, but I believe it's certainly possible. Of course, if you were alone, it's not.