Nature Done Wright

On Monday, Tom Mitchell wrote:

Walking around the "lake" [last week], we saw a snail shell on the ice a couple of feet from the shore and a couple of feet from a small hole in the ice. 

This was by the bench on the southeast between the PM tower and the Warden's Watch.

What is it and how could it have gotten there?  (Thanks, Tom!)

It is a fresh-water snail shell, as far as I know. They are usually the detritus of hungry gulls or raccoons. This time of year I'd go with raccoons. That's what Sally Teschon suggested, so she is the winner.  Marianne Herrmann concurred, and suggested having the shell analyzed. (It looked pretty sane to me.)  (Thanks, Sally and Marianne!)

More info would be welcome…