Eagles have eyelids that close during sleep. For blinking, they also have an inner eyelid called a nictitating membrane. Every three or four seconds, the nictitating membrane slides across the eye from front to back, wiping dirt and dust from the cornea. Because the membrane is translucent, the eagle can see even while it is over the eye. Eagles have an upper and lower eyelid, similar to ours, the nictitating membrane closes horizontally across the eye. Source: The American Eagle Foundation | Du

American Bald Eagle Flying, Hunting, Eating [Nature/Wildlife Documentary]