Horned grebe - breeding adults. Photo: David Larson/Flickr (CC BY-NC-ND 2.0

Horned grebe - non-breeding adult. Photo: Warren-Martin Hern/Audubon Photography Awards

Eared grebe - breeding adults and downy young. Photo: Wendy Crowe/Audubon Photography Awards

Eared grebe - non-breeding adult. Photo: Richard Mittleman/Alamy

Pied-billed grebe - non-breeding adult. Photo: Ira Rappaport/Audubon Photography Awards

Pied-billed grebe - breeding adult. Photo: Ferd Brundick/Flickr (CC-BY-NC-ND-2.0)