Anas platyrhynchos domestica
Either that or a hybrid crested duck-something else where the crest just didn't happen. But I'd assume pekin is more likely. This was, unfortunately, the closest I could get. Both ducks took off when I took a few more steps.
Some American coots there in the background.
Lat: 29.72, Long: -95.39
Spotted on Nov 3, 2012
Submitted on Nov 4, 2012