Wildlife Spotting

We had put a bunch of sea shells in our garden after a recent heavy rain we found a lot (maybe 20 on this one conch shell) of these snails all over the shells. I guess were looking for higher ground so not to drown. The shells were all slimy and there were little brown piles beside the snails that looked like it could be snail poop. They ranged in size from 5 mm to 20 mm