While visiting Shelter Island last weekend, I found the above Eastern Box Turtle shell next to the driveway at the place I was renting.
There are two mysteries:
How did it die and end up like this?
How did it get on an island surrounded by salt water?
My guess is that someone brought it to the island as a pet. It died, and they thought that they would gut it and keep the shell.
I discovered that shell smells pretty bad. They probably did, too, and left it.