While in St. Augustine, FL, I photographed many great egrets in various stages of preening and in various stages of breeding plumage. Not only do the great egrets grow long elegant back feathers in breeding season, their nares and eyelids turn a brilliant green. While this great egret preens a cascade of long feathers, its eyelid partially closes, shielding the eye from the sun. I’m not sure about the anatomy of egret eyelids. It appears that the eyelid closes from the bottom of the eye instead of the top of the eye. I suppose that’s because they plunge their heads under water after prey and it protects the eye better with that structure.