- 13.8–16.9 in
- 22–24.4 in
- 10.6–30 oz
- Smaller than a Common Goldeneye; larger than a Bufflehead.
- Canard roux (French)
- Pato zambullidor (Spanish)
- Ruddy Ducks lay big, white, pebbly-textured eggs—the largest of all duck eggs relative to body size. Energetically expensive to produce, the eggs hatch into well-developed ducklings that require only a short period of care.
- The bright colors and odd behavior of male Ruddy Ducks drew attention from early naturalists, though they didn’t pull any punches. One 1926 account states, “Its intimate habits, its stupidity, its curious nesting customs and ludicrous courtship performance place it in a niche by itself…. Everything about this bird is interesting to the naturalist, but almost nothing about it is interesting to the sportsman.”
- Pleistocene fossils of Ruddy Ducks, at least 11,000 years old, have been unearthed in Oregon, California, Virginia, Florida, and Illinois.
- Ruddy Ducks are very aggressive toward each other and toward other species, especially during the breeding season. They are even known to chase rabbits feeding on the shore.
- Though Ruddy Ducks are native to the Americas, one population became established in England after captive ducks escaped in 1952. This population grew to about 3,500 individuals by 1992, and now appears to be expanding into the Netherlands, France, Belgium, and Spain.
- Ruddy Ducks get harassed by Horned Grebes, Pied-billed Grebes, and American Coots during the breeding season. The grebes sometimes attack Ruddy Ducks from below the water, a behavior known as “submarining.”
- The oldest Ruddy Duck on record was at least 13 years, 7 months old.
Ruddy Ducks breed in wetlands and reservoirs from southwestern Canada through the western United States and Mexico, as well as in scattered sites in the eastern United States and on the Caribbean islands. About 86 percent of the breeding population is concentrated in the prairie pothole region of south-central Canada and north-central United States. Their breeding habitat includes large marshes, stock ponds, reservoirs, and deep natural basins. Migrating Ruddy Ducks stop in a variety of habitats, most often on large, permanent wetlands, lakes, and reservoirs. They spend the winter throughout the southern half of the breeding range, also moving into wintering habitat that spans most of the United States and extends through Mexico to Central America. Their wintering habitat includes freshwater wetlands, lakes, and reservoirs as well as brackish bays, coastal marshes, and tidal estuaries.
Both adults and ducklings eat aquatic insects, crustaceans, zooplankton, and other invertebrates, along with small amounts of aquatic plants and seeds. They forage mostly by diving to the bottom of shallow ponds, straining mouthfuls of mud through thin plates on their bills and swallowing the prey items that are left behind. Occasionally they strain food from the surface of the water. Midge larvae form a large part of their diet. Other food items include water fleas, worms, amphipods, seed shrimp, snails, caddisfly larvae, dragonfly nymphs, predaceous diving beetles and their larvae, bugs, water boatmen, brine fly larvae, crane fly larvae, mosquitoes, mayflies, and plant material from arrowhead, pondweed, muskgrass, bulrushes, bayberry, spikerushes, water lilies, duckweed, and more. Plant material is more common in their diet during migration and winter than during the breeding season.
- Clutch Size
- 3–13 eggs
- Number of Broods
- 1-2 broods
- Egg Length
- 2.3–2.7 in
- Egg Width
- 1.7–1.9 in
- Incubation Period
- 20–26 days
- Nestling Period
- 1 days
- Egg Description
- White to yellowish white, with a pebbly texture.
- Condition at Hatching
- Active, well-developed, and covered with down (dark above and lighter below).
The nest is usually made of dead, dry plant materials, though some are built entirely with green vegetation. It starts as a platform and becomes more bowl-like throughout the construction process, with an inner cup measuring 4–12 inches across and 0.5–5 inches deep. Ruddy Ducks usually weave a canopy of vegetation over their nests.
Usually placed 2–10 inches over the water in cattails, bulrushes, or grasses, the nest is supported and well-concealed by vegetation. The female chooses the site.
Ruddy Ducks spend the vast majority of their time on the water. They are fast fliers but have little maneuverability in the air, and they tend to swim and dive rather than fly to escape predators—which include Red-tailed Hawks, Great Horned Owls, mink, raccoons, and red foxes. Ruddy Ducks are very aggressive toward each other and toward other species, especially during the breeding season. Unlike most ducks, they form pairs only after arriving on the breeding grounds each year. Males perform unusual courtship displays in which they stick their tails straight up while striking their bills against their inflated necks, creating bubbles in the water as air is forced from their feathers. They punctuate the end of the display with a belch-like call. Courting males also lower their tails and run across the water, making popping sounds with their feet. Most males pair up with one female each for the duration of the breeding season, but some take multiple mates. Their eggs are proportionally the largest of all waterfowl. The ducklings hatch well-developed and active, receiving minimal care from the mother and none from the father. Ducklings are preyed upon by Black-crowned Night-Herons, Ring-billed Gulls, California Gulls, mink, and raccoons.
Ruddy Duck populations are stable across North America according to the North American Breeding Bird Survey. They can be found throughout the year in the U.S. and Mexico, and during the breeding season in Canada. Though they were hunted during the 1890s (and numbers probably declined during that time), they are not popular with hunters today. The U.S. Fish and Wildlife Service records about 50,000 Ruddy Ducks shot by hunters each year. Like all waterfowl, Ruddy Ducks are susceptible to poor water quality, pollution, and oil spills. The population in Chesapeake Bay dropped significantly between 1955 and 1979, probably because of habitat degradation from exotic species invasion and pollution. Ruddy Ducks depend heavily on wetlands in the prairie pothole region of North America, where grazing, burning, and wetland drainage have degraded portions of their habitat. Their future success will depend in large part on the protection and restoration of that region.
Short-distance migrant. Ruddy Ducks migrate in small groups of 5–15 individuals, usually at night. They follow several migratory corridors fanning to the southwest, south, and southeast from their northern breeding grounds. In California, breeding birds may move to coastal areas. Some populations in the Caribbean islands, Mexico, Guatemala, and El Salvador stay in one place year-round.
Find This Bird
Look for Ruddy Ducks from fall through spring on open water, both inland and in protected coastal areas such as harbors and small bays. During the day, they often sleep with their heads tucked, and they gather in tight flocks. Because of this, these little divers often look like gray-brown or chestnut blobs with a long, rounded tail (for a duck, anyway) held up at an angle. In summer, look for them swimming and diving in wetlands of the prairie pothole region and the interior West. The male’s white cheek patch is often distinctive from great distances.