Did You Know... We, as Canadian Bird Photographers strive for sharp photos...especially the eye. The accepted standard of a good photograph of a bird includes a tac-sharp, clear, shiny eye. But sometimes that isnt always possible. Woodpeckers have what is known as a third eyelid or nictitating membrane to protect the eye from flying debris such as woodchips. A millisecond before its beak hits the tree trunk, the woodpecker unconsciously tautens its nictitating membrane. Birds can actively control this and it goes from side to side vs up and down like the normal eyelid. This helps to prevent the bird from developing eye injuries which would otherwise be induced by its continual hammering. If you look closely, you will see a partially closed nictitating membrane on this Hairy Woodpeckers eye.
Posted on: Fri, 26 Dec 2014 23:18:28 +0000
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