About Oxyura jamaicensis (J.F.Gmelin, 1789)
The ruddy duck (Oxyura jamaicensis) is a small, compact duck species with a stout, scoop-shaped bill, a slightly peaked head, a fairly short thick neck, and a long, stiff tail that it typically holds cocked upward. The species has a short, stout scoop-shaped bill adapted for underwater foraging. On average, females are smaller and weigh less than males. Breeding (summer) males have a blackish cap that contrasts with bright white cheeks, a rich chestnut-colored body, and a bright blue bill. Non-breeding (winter) males are dull gray-brown on the upper body, paler on the underbody, and have a dull gray bill. Females and first-year males are brownish, similar in appearance to winter males, but have a blurry stripe across the pale cheek patch. In flight, ruddy ducks show solidly dark tops on their wings. Ruddy ducks are strong swimmers due to their short stature, but taking flight is a much more labored task for them. Compared to other ducks, ruddy ducks rarely fly; when they do fly, they stay close to the water and use a very fast wingbeat. A distinctive physical feature of this duck taxon is the modified trachea, inflatable air sacs, and esophagus that are used for courtship and display behaviors.
