What Kind Of Snake Has Blue Eyes?

　　A snake about to shed its skin?  One you can be less afraid of?

　　Here is a picture of a garter snake with blue eyes.  The eyes are only blue in the photo because the loose skin over its eyes (and rest of body) is about to be shed.  So most snakes at some point in their lives will have blue eyes. The eyes revert to yellow, brown or other usual colour once the skin is shed.

　　Snakes about to shed their skins are normally slower moving and less responsive to their external environment, too much energy devoted to growing the new skin, I suppose.  They also can't see as well as usual -- but their sense of smell is fine.  And smell is how they locate their prey, usual.

　　Garter snakes are very common in North America, and virtually harmless.

　　Some very white or nearly albino snakes also end up with blue eyes.  See example here.  Some varieties of corn snake (another harmless North American variety) are being bred to be pure white.  Some of these specimens have red eyes (true albinos), others have blue eyes.

What you were witnessing was a snake that was shedding its skin

Tree boa

One that is going to shed it's skin soon

There is a genetic mutation called "Leucism", which results in an all-white(or mostly-white)snake with blue eyes.  This is a recessive gene that causes the white pigment to "take over" and "push out" the other color pigments that would normally be present.  It is NOT the same thing as albinism, which is simply a lack of pigment melanin, which produces black or black-brown coloration.