This appears to be a fairly common cross bred Mallard. We have large populations of these around us where white was somehow introduced into a flock of otherwise wild colored wild Mallards and the offspring hatch with a bib or various colors. A lot of people buy their children ducklings as presents and when the realize how much work and how messy they are they turn them loose and they interbreed with wild populations and produce a huge array of "pretty" birds. On a recent shopping trip in a larger city east of us we came across a huge flock of these type of birds. There were probably 20-30 regular wild (gray) Mallards and then the rest of the flock was the same size or just slightly larger, but they were kahki, black bibbed, blue bibbed, golden, dusky, black bibbed with some runner-pattern (almost magpie marked) etc... etc...
