Hmm-mm. There may be a reason why "natural pools" are mostly a European thing: they killed off most of their wildlife centuries ago, so their natural pools may not acquire the sort of competing population green pools here, do.

Actually, I've been thinking about that a bit. My PERSONAL collection of critters found in pools include: black snake, ring-neck snake, garter snake, Eastern water snake, Canada geese, mallard ducks, rats, mice, shrews, bullfrogs, leopard frogs, toe biters, tiger salamanders, chipmunks, and black widow spiders.

The things I recall forum members reporting, during the various incarnations of the PoolForum include deer, black bear, skunks, in addition to the things above.

However, if you put one of those pools in this area of the south-east, you'd be able to add: great blue heron, little green heron, water bugs galore, every kind of frog known to man, and . . . and snapping turtles.

Even I try to avoid swimming with those things!