The deer would break the ice just about every night, at the warmer edges of the pond (in front of the chairs in the pics). And then the deer, and various other animals, would converge on those areas for water, during those many frozen winter days this winter. You can see the tracks in these pics. (no human tracks in the pics – as I could not traverse the yard this winter, due to injury)
And in the middle picture, the rotting ice is readily noticeable in the back center of the pond. 40 degrees today.
Something sad to think about – our outdoor cats also worked at breaking the ice in their water bowls, with their little soft paws. And break the ice they did – till it got too damn cold, and the water froze up, all in disarray, from the kitty paws that kept working the ice till the very end – all froze up hard and lumpy. (But we put out several bowls of hot water for them each day.)