The great egret
The great egret (Ardea alba) is also known as the common egret, large egret or (in the Old World) the great white heron.
Apart from its larger size, the great egret can be distinguished from other white egrets by its yellow bill and black legs and feet. But its never that easy for ID, as always these birds change, and the bill may become darker and the lower legs lighter in the breeding season. These pictures are of a typical Great Egret in Mai Po.