Canada- south of Edmonton, Grebes? (1 Viewer)

[KhostAdenplusmore]

I was at a large reed lined marsh, south of Edmonton on July 10th, and watched the largest group of Pied-billed Grebes that I have encountered. There were multiple family groups and I had counted over 40 Pied-billed Grebes (plus a couple of Eared Grebes). But this one group seemed different, with some very white heads and perhaps bills that seemed to be yellow. The last photo is of a group of what I consider to be standard looking Pied-billed Grebe adult and juveniles.
Are the white headed birds perhaps some type of leucistic Pied-billed Grebes, or is it something else?
Thanks for your thoughts, z.

 

[aeshna5]

Not grebes but juvenile American Coot.

 

[AveryBartels]

Agreed with aeshna5, fledgling American Coots.