Putting little blindfolds on turtles has gotten to be a widespread scientific pursuit. Find out all the different ways, and reasons, why you might want to blindfold a creature that's too slow to run away from you.

A turtle has just been hatched. It's newborn, in danger, and its eyes are perhaps a half inch off the ground. How does it find its way to the ocean? There's been speculation that hatchling turtles listen to the sound of the waves, or tune in to the Earth's magnetic field. But nobody knew for sure — until scientists started putting little blindfolds on them, and everything became clear (clear for the scientists, not the turtles). Without their vision to guide them, the turtles just circled. The turtles just looked around.

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Figuring out what visual clues the hatchlings were responding to required yet more blindfolds. When the turtles got unilateral blindfolds — eye patches — they circled, for quite some time, towards the seeing eye. The newborn turtles managed to find the sea because they went towards the light.

While turtle behavior is interesting, I find it more interesting that there is an entire genre of science that's all about turtle blindfolding. One scientist noted that, in a lab, turtles with eye patches did circle towards the only eye that could perceive light for some time, but then turned and circled into the darkness for a while. Freshwater turtles display the same behavior — circling aimlessly when blindfolded, but towards the light when wearing an eye patch. Researchers speculate that freshwater turtles would want to turn away from tall vegetation and towards light, open areas like streams and ponds.

And this fits into a larger science of turtle bafflement. If you're wondering how far a turtle can be taken from its pond and find its way back, any turtle can find its way home from 100 meters, but none can from 1.6 kilometers. So I guess if you've started a blood feud with a turtle, just get about a mile away, and he'll never find you.

Image: Brocken Inaglory

[Sources: The Behavior of Fish and Other Aquatic Animals, Turtles of the United States And Canada, Sea-Finding Behavior of Loggerhead Hatchlings, The Biology of Sea Turtles.]