We have a few small creaks near by. This is a possibility I had not thought of. He wouldn't have been there naturally though, as he is not native to California. It would have been a very large bird, like a hawk, to carry him.
We found a RE Slider on our driveway in Petaluma, CA in August... went around the neighborhood asking if anyone lost him, but could not locate the owner. We have given him a home, 40 gallon tank, 2 filters, floating dock, food including fresh live fish and red leaf lettuce. He has a crack on the...