Little Blue Heron

A small, dark heron arrayed in moody blues and purples, the Little Blue Heron is a common but inconspicuous resident of marshes and estuaries in the Southeast. They stalk shallow waters for small fish and amphibians, adopting a quiet, methodical approach that can make these gorgeous herons surprisingly easy to overlook at first glance. Little Blue Herons build stick nests in trees alongside other colonial waterbirds. In the U.S., their populations have been in a gradual decline since the mid-twentieth century.

http://www.allaboutbirds.org/guide/Little_blue_heron/id