Never have I seen bubbles frozen in ice. I am not sure what phenomena has occurred to cause this. It is remarkable to see. We have a backyard pond which we built almost ten year ago. For years we had koi. They were wonderful fish that went silent in winter but always came back no worse for the wear in spring. A year ago, our pond was visited by a couple of mink which quickly helped themselves to our koi. By then, they had grown more than a foot long. It was sad to see the struggle.
I look at these frozen bubbles rising from the depths of the pond and think to myself that they are the last breath of our missing koi. What else could they be?
Nikon D610 1/90 sec f/3.0 (105mm f2.8) - 3604 42°25'18" N 71°49'36" W