An online resource based on the award-winning nature guide – maryholland505@gmail.com

Owls & Eyelids

All birds have three eyelids – like humans, they have an upper and lower eyelid.  Owls are among the only birds that have a larger upper eyelid than lower eyelid. They are the only birds that blink like humans, by dropping their upper eyelids. But when owls sleep, they close their eyes the way other birds do—by raising the lower lids.

Beneath the two outer eyelids birds have a translucent nictitating membrane, sometimes called a “third eyelid.”  This membrane sweeps across the cornea from the inside corner of the eye to the outer edge of the eye. It moistens and cleans the cornea, especially in flight.  It is also drawn across the eye when there is a chance the eye might be scratched or damaged such as when capturing prey, flying through brush or feeding their young.

In summation, one could say that owls have three eyelids for each eye: one for blinking (upper), one for sleeping (lower), and one for keeping their eyes clean and protected (nictitating). (Photo: Snowy Owl sleeping, with lower eyelids raised.)

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9 responses

  1. Peggy Timmerman

    Amazing photo! Thanks for this cool information. Nature is incredible.

    December 7, 2020 at 8:39 am

  2. Domestic felines have a third eyelid, if and when that is seen under normal awake mode (which is not normal) if could indicate a not so obvious medical problem looming! Beautiful Owl Photo! They are so gorgeous! 🙂 ❤

    December 7, 2020 at 8:39 am

  3. Stein

    Did you capture this image in Vermont? I know that sometimes Snowy Owls drift down to Plum Island in Massachusetts, but not often. Is Vermont within the owls’ normal range?
    It’s a magnificent image! Thanks!

    December 7, 2020 at 8:58 am

    • Hi Stein! Yes, this Snowy was in Shelburne, VT this weekend. There’s also been one in Morrisville, I believe. Certain winters you can find them all over Vermont, especially in the Champlain Valley near Dead Creek. Plum Island is a favorite spot as well!

      December 7, 2020 at 9:21 am

  4. Wonderful photo Mary, and fascinating info on the eyelids!

    December 7, 2020 at 9:54 am

  5. Alice

    Wonderful dreams, beautiful Snow Owl! You are ‘an animal whisperer,’ Mary, that the owl is sleeping, while you are near-ish. They like to be in the marshes & on the beach in Duxbury, MA, where I have seen them.

    December 7, 2020 at 10:05 am

  6. My goodness, so beautiful! Do they sleep out in the open, as the owl in this photo seems to be doing?

    December 7, 2020 at 11:32 am

  7. Cheryl Johnson

    On Mon, Dec 7, 2020 at 7:56 AM Naturally Curious with Mary Holland wrote:

    > Mary Holland posted: ” All birds have three eyelids – like humans, they > have an upper and lower eyelid. Owls are among the only birds that have a > larger upper eyelid than lower eyelid. They are the only birds that blink > like humans, by dropping their upper eyelids. B” >

    December 8, 2020 at 8:54 am

  8. Susan Brown

    Mary, I found a lodge in a small pond made of cattails. I’m guessing it’s a muskrat lodge based on the info in your book. Is there a way I could send you a picture for your opinion on it?

    December 18, 2020 at 10:44 am

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