Why are Egrets White?

[Rich Swanner]

I wonder what the white does for them? I see them from far away, don't predators and their prey?

[John Hawkins]

I'm by no means a expert, but I think I read once that by being white they look like clouds from below the water to the fish. So the fish don't swim away and the fishing is easier for the egrets.
John

[John Chardine]

John may be right. A lot of predators are white below for this reason, and many are dark above for the same reason of camouflage to prey above them against a dark background (penguins for example). Being white above is useful in warm climates -where egrets tend to come from- because the heat of the sun is reflected away rather than absorbed.

Another point, although not probably relevant here is that pigmented feathers are harder wearing than white feathers. You see this in the white tips of flight feathers which tend to wear much more than darker areas.