I have noticed foraging flocks in farm fields in the fall.

The most common flocks I see are of Canada geese: in school athletic fields, on golf courses, or by the river.

I have seen large groups but I don't know that they were foraging as they were not on the ground. It was more like a "meeting" in the sycamore behind my yard. I believe it was fall or early winter because the tree was bare of leaves.

The other flocks that I have seen in my yard were wild parrots and Cedar wax wings. I have also seen groups of pigeons and black birds "brewers?" or "red wing?" on the now weed covered ex dump that is out by the San Francisco bay.