Hey, I need some help identifying this bird. When I originally saw it I thought it might be a Mallard x Mexican Duck hybrid, but after reading a lot I was unable to find a sure way to distinguish it from a Mallard x American Black Duck hybrid. Also a very experienced birder told me it could just be a mallard with off coloration because it isn't to far off from a mallard. It has a green head and neck with gray streaked cheeks. Body and tail are mostly mallard coloration with an overall darker tone and brown patchwork throughout. The duck was also light brown underneath on the belly rather than white. Below is a link to the pictures I took of the bird for reference. Any help I could get would be greatly appreciated thanks.