It must be getting close to breeding season for the egrets we see here. I saw some today with plumage beginning to show. Egrets belong to the heron family and develop fine plumage during the breeding season.

A "Cool Fact" from http://www.allaboutbirds.org/guide/Great_Egret/overview:

"The pristinely white Great Egret gets even more dressed up for the breeding season. A
patch of skin on its face turns neon green, and long plumes grow from its back. Called
aigrettes, those plumes were the bane of egrets in the late nineteenth century, when such
adornments were prized for ladies’ hats."