It is their winter colors. A few weeks before they leave they get the summer colors.

It's unusual to see 30+ in flock and that is why I stopped to watch. There were probably 50 in sight of me scattered around. I sort of suspect they arrived together recently and just haven't spread out yet.. There was this one big flock just sitting there. It's not to unusual to see several in one area, feeding I assume. But I have never seen them flocked up like that.

I have had on occasion one that wouldn't be scared of me and wouldn't dive but they always kept a safe distance too. These just showed no fear. That is why I wonder if it was the paint job? Maybe the pattern with the eye had something to do with it? Of course duck season isn't open yet and that could be make more cautious too.