The imprisoned dolphins and whales at Marineworld seem to see pretty well out of the water. As a kid I was pretty comfortable with my eyes open in pools and clear enough fresh and salt water, I could find coins in a pool and crabs on bottom of the ocean, I couldn’t tell what kind of coin easily but I could catch a crab if I could keep up with it. Just depends on how good a look they expect, but if they can see and recognize a boat from underneath they may want to find out what the part out of the water looks like even if it’s not as clear of an image.