We are starting to shoot more and more Mexican mallards each year, but mottleds are pretty rare wheareas are. I've shot a lot of mms in Mexico and south tx and a ton of mottled growing up in Sw LA. I'm pretty sure the bird on the right is a mottled duck. And the one on the left is a Mexican mallard. He doesn't have the heavy whitewing stripe of the ones we kill in Obregon but definitely has the blue speculum feathers.

Beautiful pics.

thanks for the side by side pics.

Here's some Mexican mallard pictures. From Obregón last year

Nice pictures