Ruddy duck males and females are different in appearance, and males change appearance depending on the time of year. During the summer male ruddy ducks have rich chestnut necks and bodies. The crown, nape, and tail, which are held erect or horizontal to the water, are dark brown. Males have pure white faces. Females have a dark line across the face. Females and young ruddy ducks have barred bodies that lack any chestnut color. During the winter, male ruddy ducks resemble females except for their white face. Ruddy ducks have large, flat pale blue bills. Males tend to be larger than females in weight and wingspan.
In the summer male ruddy ducks look similar to females. In the winter male ruddy ducks have their breeding plumage, with rich, chestnut colored feathers. During this time their bill becomes bright blue as well.
Ruddy ducks are native to North and South America. These stiff-tailed ducks nest in western and central Canada as far east as the Great Lakes region and south to central Texas and southern Mexico. In the winter they are found throughout most of southern North America and central America, from California through the Great Lakes region to the Atlantic coast. Ruddy ducks were introduced to England in 1960 in Gloucestershire.
Ruddy ducks inhabit permanent freshwater marshes, lakes, and ponds during their breeding season. These pools contain a considerable amount of vegetation in which these ducks hide their nests. During the winter ruddy ducks prefer shallow marshes and coastal bays.
Ruddy ducks breed seasonally. They migrate to breeding grounds in late winter. When they get to their breeding areas males begin to perform courtship displays. A male swims around a female with his tail tilted forward and neck outstretched. He then slaps his chestnut-colored chest with his bright blue bill while making a courtship call. The male also uses his tail to stand and scoot across the surface of the water. When the female is satisfied with this performance, she stretches her neck with her bill open.
Ruddy ducks breed in spring and summer months, from May to August. When they arrive on the breeding grounds, females construct nests of aquatic plants just above the water level. They often build a dome over the nest to hide it from predators. About 4 weeks after arriving at the breeding grounds, females are ready to nest. Sometimes, though, females are ready to lay eggs before they have finished their own nests and they may simply lay eggs in unprotected areas that hatch after 23 to 26 days. Young ruddy ducks are well developed when they hatch. They stay in the nest 1 day after hatching and then are led away from the nest and into the water. At this point young ruddy ducks can dive to find food and can defend themselves. Parents abandon their young 20 to 30 days after hatching, but it takes another 20 to 35 days after that for the young ruddy ducks to learn how to fly.
Female ruddy ducks construct and cover nests for their young, invest energy in making the eggs, and do all of the incubation of eggs. They also aggressively protect their young for several weeks after they hatch. Male ruddy ducks don't care for their young. They may remain near the female during incubation and after the young hatch, but they don't make any effort to protect or feed them.
Althugh most ruddy ducks die when they are young, if they survive to adulthood they can live up to 13 years in the wild in their native range.
Ruddy ducks are clumsy on land, their legs are set far back on the body, making it difficult for them to walk. The same placement of their legs makes them exceptionally fast and agile in the water. They can dive or sink into the water with little effort. While diving, the feet paddle simultaneously and wings remain closed. To take flight these ducks must beat their wings rapidly and run along the surface of the water. Ruddy ducks fly just above the water, even during migration when they travel in medium to large sized flocks at night to their summer breeding grounds.
These ducks are usually found alone, in pairs, or in small groups of eight to twelve. They generally don't flock with other kinds of ducks or geese.
Ruddy ducks do not actively defend a territory, nor do they restrict themselves to a given home range for any part of the year.
Ruddy ducks usually don't make many calls or other sounds. During courtship, males perform an elaborate display accompanied by a call in order to attract a mate. Their calls sound like: chuck-chuck-chuck-chuck-chur-r-r; and ip-ip-ip-ip-u-cluck; and tick, tick, tick, tickety, quo-ack; as well as chica, chica, chica, chica, quak.
Ruddy ducks are omnivorous. Their diet consists mainly of aquatic invertebrates and plants. Their wide bill is used to grab food when they dive and then sort out parts they want to eat. They mostly eat plant seeds, leaves of aquatic plants, crustaceans, and midge larvae and pupae.
Ruddy ducks have the ability to sink below the surface of the water to escape predators. During breeding season they make nests using vegetation, which camouflages nests and makes them more difficult for nest predators to find. Females and nestlings have drab feathers that help them blend in with their surroundings as well.
Eggs and nestlings are taken by predators such as racoons, mink, American crows, black-crowned night herons, ring-billed gulls, and California gulls. Adults are preyed on by red-tailed hawks, great horned owls, red foxes, mink, and possibly Swainson's hawks. Ruddy ducks are also legally hunted in North America and Europe.
In the ecosystems in which they live, ruddy ducks act as predators on soft-bodied invertebrates such as midge larvae and crustaceans. They also eat aquatic vegetation. Ruddy ducks are preyed on by many organisms, including raccoons, mink, American crows, red-tailed hawks, and great horned owls. Ruddy ducks are used as a host by parasites that reside in their intestinal tracts.
Since their introduction to Europe in the 1960s, ruddy ducks have also impacted ecosystems by threatening native white-headed ducks (Oxyura leucocephala).
Ruddy ducks do not harm people.
In the past, ruddy ducks were hunted for the quality of their meat. There continues to be regulated sport hunting in the United States and Europe. (Gooders and Boyer, 1986)
Ruddy duck populations are considered stable throughout their range, and are considered a species of "Least Concern" on the IUCN list.
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