(May 18, 2018) Sometimes we get questions about the strange appearance of the eyes of some of the Giant garter snakes we feature in Conservancy media. Some say it looks like something out of a horror film (AKA “scary movie”).

It normally looks like a filmy-looking cover over the eyes, at least in some of the photographs we share.

Actually, this is what is called a nictitating membrane, or, as some would say, third eyelid. Usually, it is considered to be transparent, and enables the animal to continue to see while protecting or moisturizing the eye.

And Giant garter snakes aren’t the only animals in the Natomas Basin that have this nictitating eye lid. Fish, amphibians and some birds are among the creatures that have it. There are many beavers in the Natomas Basin, and they have them as well, although they are thought to be clear. Bald eagles too.

So, don’t be afraid. When you see this, it is normal. At least for our friends on the Conservancy preserves and many other places in the natural world.