Cinnamon Teal, Anas cyanoptera, are a western species. The drake is reddish brown overall. Both hen and drake have a pale blue shoulder patch on the front edge of the wing. The Cinnamon Teal hen can easily be mistaken with the Blue-winged Teal hen. Cinnamon Teal hens are warmer brown, slightly larger and heavier-billed than Blue-winged Teal hens.
In the Pacific Flyway, cinnamon teal are far more common than blue-wings. The hens look alike and the habits of both species are similar.
The pale blue forewing patch is the best field mark, as drakes are usually in eclipse until January or longer.
Drakes have a whistling peep; hens utter a low quack.