Black-bellied Whistling Duck (Seen in The Woodlands, TX)
Black-bellied Whistling Ducks - Their high-pitched whistle gives them their name. Here we have the entire choir whistling a tune! These handsome ducks, a tropical species (Mexico and Central America) have been moving farther north in Texas. They form long-term bonds.
  (Juveniles above and below) Black-bellied Whistling Ducks mostly like to nest in trees. Just one day after they hatch, the ducklings jump out of the nest, and head for water with their mom!

Blue-winged Teal

Blue-winged male Teal in breeding plumage (note the blue-gray head and the wide white crescent in front of the eye), male Blue-winged Teal (breeding season), male & female
Blue-winged Teal, female The male looks much like the female when they arrive in our South Texas area in the fall. The difference is that the female has soft quacking sounds, and the male has a large peeping/twittering repertoire.
Green-winged Teal

"It's not easy to tell a female Green-winged Teal from a female Blue-winged Teal, especially when you can't see the colors on their open wings. The Blue-winged Teal female has a white patch at the base of her bill, the female Green-winged Teal has white that is barely noticeable at the base of the bill. Also check out the beige mark right under, and at the side of, the tail on the female Green-winged Teal, a little noticed, but great clue to tell them apart." (Stoke's Birding Blog)

Green-winged Teal, male  
Cinnamon Teal
The male Cinnamon Teal is easy to identify during breeding season - his head, neck and underparts are a bright cinnamon-red. The female, however, looks very much like the female blue-winged teal. How can you tell them apart? Wait until breeding season, and then notice with whom they are swimming!!
Canvas-backed Duck
Mallard Duck (Seen in The Woodlands, TX)
Mallard, male Mallard, female
Mallard eggs - the female lays on the eggs after they have all been laid, thus assuring that they all hatch at the same time!
Lesser Scaup
Lesser Scaup, male Lesser Scaup, female
Muscovy (domestic) (Seen in The Woodlands, TX)
Wood Duck (Seen in The Woodlands, TX)
Wood Duck - I think God rested after he created this gorgeous bird! What a sight!! These ducks were nearly wiped out at the turn of the century, when their feathers were used for everything from ladies' hats to artificial trout flies.  They were placed under federal protection in 1918,
Wood Ducks, male and female. 
Notice her distinctive eye.
Wood Duck family.  The wood duck builds her nest in tree cavities. Soon after they hatch, the tiny ducklings stand in the entry, then drop to earth unharmed!
American Wigeon

"A common and increasingly abundant duck, the American Wigeon breeds in northwestern North America and is found throughout the rest of the continent in migration and in winter. Its small bill and the male's white forehead, as well as certain aspects of nesting and feeding behavior, distinguish this species from other dabbling ducks." (Cornell)

Northern Shoveler
It's easy to identify the Northern Shoveler
with that gigantic bill! 
It usually eats small plants and animals by straining water through the comb-like edges of its bill.
Gadwall, female  
Ring-necked Duck
How strange that this should be called
"ring-necked" when it's the ringed BILL
that you see! (It actually has a barely visible cinnamon neck band.) 
Ring-necked Duck, female