Herons have a second transparent eyelid used to clean or wipe the eye without losing vision - essential in a spray environment such as when catching a fish. In the right-hand image here, you see that eyelid 'closed'.
Avian Grey is sister site to American Grey | light and features bird photography that seems to form an increasing part of my current portfolio. My thanks go to Henry the Heron who became very much my passport to the Avian World.
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