I saw at least one lifer species of Mallard lookalikes this trip - Mottled Ducks. They're a rich, mahogany brown over the back with pale, grey-beige heads, but Mallard colours can vary so the clincher detail is that black spot at the gape. Males and females very similar but for bill colour. Females have black or mottled bills, males have bright yellow - so this is a female. When you see large numbers of apparently all female "Mallards" in the southern US, it's a good idea to look closely for black gape spots. I may also have seen Mexican Ducks, which are another all "female"-coloured Mallard lookalike with mahogany-toned plumage, but I don't have any shots that turned out to be Mexicans. All the possible shots turned out to be either Mallards or Mottleds.
After a foot of snow, it's now pouring rain outside. Yuck, what a mess! And not even good light for snapping birds in the garden. I'm gonna spend the day sewing. Will also catch up on BF browsing when I take sewing breaks.