The little or common or small Egret. you can clearly see the yellow feet and darker bill, here on a bird in the shadows of a river in MaiPo.
In the 19th and early part of the 20th century, some of the world's egret species were endangered by relentless plume hunting, since hat makers in Europe and the United States demanded large numbers of egret plumes, leading to breeding birds being killed in many places around the world. Hence the founding of the RSPB in the UK and the the great egret in flight was chosen as the symbol of the National Audubon Society, which was formed in part to prevent the killing of birds for their feathers.
Many egrets are members of the genera Egretta or Ardea which also contain other species named as herons rather than egrets. The distinction between a heron and an egret is rather vague, and depends more on appearance than biology.
The word "egret" comes from the French word "aigrette" that means both "silver heron" and "brush", referring to the long filamentous feathers that seem to cascade down an egret's back during the breeding season.