There was an animal in the reeds in the little stream by my house (really a canal to drain the park's water). It was the size of a medium-sized dog. I could only see its back at first, rolled into a ball like it was grooming itself. Dog?? nooo. The fur was matted, and... familiar somehow. Only when it un-curled and swam away was it plain.
It was a beaver. Flat tail and all.
The critter is discussed on page 7 of the weekly Potsdam am Sonntag 2013-11-17 00:00:00. For a long time, one could plainly see the tree he took down in the park. A good 20 cm trunk, nibbled clean through.
In the sand of the same stream, there's a rock. But, there's a kind of path in the sand leading to it, the same size as the rock, a zigzaggy path, no particular direction. And there's another rock just like it... also with a path.
Did that rock just move?
They're dark gray and pink, and they're freshwater clams. Every minute or two, they push themselves a centimeter or so with a pink foot.
I think they spend most of their lives burrowed in sand. Out and about... looking for mates, I guess!