This is a Great Egret. They are common on Chincoteague National Wildlife Refuge but it is always neat to see them. This one was looking for lunch in a small pool and I liked the contrast of the water with the bright while feathers. This one is also in breeding colors which you can tell by the bright yellow/orange bill when it is not, only the lower portion of the bill is yellow. The second photo has three of them in a marsh where one is about to consume the lunch it just caught.
The Great Egret in the foreground has just caught a fish and you can see its tail if you look carefully.