Ring necked Ducks

Tufted Ducks in California would be a great sighting! They're rare vagrants here. A single Tuftie drake in Washington caused a twitch among Northwestern birders recently (bird is still continuing actually).
Ring-necked Duck is the name of your birds (I also see a Bufflehead [Bucephala albeola] in there). Their name comes from a chestnut ring around the neck of the drake (visible in photo 2). I too think Ring-billed Duck would be a more appropriate name, as the chestnut collar isn't always visible.

Hmm, maybe the use different names some places... But the Tufted Duck have that tuft on the head.
Maybe Liam know?

According to this link it is also known as "Tufted Duck", or' Ring-bill Duck" in Kentucky.
http://web4.audubon.org/bird/BoA/F39_G5d...

It says Ring-necked duck on Wikipedia and eol.org... But Ring billed duck would be a better name on that duck

Stian,is this by any chance also known as Ring billed duck?

You also have some American coots there...