I have several files of this duck. iBird identified one as a LESSER Scaup (Image _65A3032-2) and one as a GREATER Scaup (Image _65A3035-2), each with over 80% confidence. Lesser Scaup are more common in the area (Southern California), but this bird does not have the little "bump" on the head that I typically associate with Lesser Scaup. Hence, I submitted to iBird to see what guidance i could get. No help, sorry to say.  These two photos were taken in Borego Springs, CA, at a pond on a resort go