Bird Watching: BLUE and green headed Mallard Ducks!, 1 by Grasmussen

Grasmussen wrote:
This afternoon at Northwood Park, there were about 300 Mallards in a small area of open water, and on the surrounding ice. It was a bright sunny day. From my vantage point the ducks on the left had blue heads. The duck on the right were at a different angle to the sun, and had green heads. Near the center there was a transition zone as the ducks moved through the colors changed. I find it hard to believe anyone could think it was anything other than iridescence! At time the color can also appear Black.

A Blue headed Mallard from the left side of the pond.