The Itsy-Bitsy and the Mysterious Eyes

We were introduced to the Itsy-Bitsy in the 135 page book of the same name, where over twelve chapters we came to know them well, and now we have a follow on adventure.

Mysterious eyes are revealing themselves to the green folk of Bogmire, that tiny town which exists below a sodden marsh, and many of them are scared.

What are the eyes, who, or what, do they belong to?