DUCKS, GEESE, AND SWANS: Anatidae

PHYSICAL CHARACTERISTICS

Anatids (members of the family Anatidae) are medium to extra-large birds with stocky bodies, webbed feet, and a flat bill. Coloring varies but is primarily brown with white, black, and metallic green accents. The smallest species stands 13 inches (33 centimeters) and weighs no more than 0.5 pounds (0.2 kilograms) while the largest grows up to 6 feet (1.8 meters) in length and weighs up to 49 pounds (22.5 kilograms).

GEOGRAPHIC RANGE

Found on all continents except Antarctica.

HABITAT

Anatids need water. Some require fast-flowing streams; others prefer rainforests, tundra, or even the lava fields of volcanoes. Marshland is another common habitat for these birds.

DIET

Despite the fact that most geese, ducks, and swans require water bodies for survival, not all species eat aquatic food. Some species are vegetarian and eat primarily seeds, roots, leaves, and stems. Others eat insects, and still others thrive almost exclusively on aquatic invertebrates (water animals without backbones). Some anatids favor plankton and algae (AL-jee).

BEHAVIOR AND REPRODUCTION

Nearly half of all anatids migrate (move from region to region, seasonally), and most of those that don't tend to wander over a wide area to remain near a plentiful water supply.

Anatids are known for their flock formations, which experts believe may help them in locating food as well as protect them from predators, animals that hunt them for food. Aside from humans, primary predators include red foxes, badgers, raccoons, coyotes, skunks, weasels, minks, owls, skuas, American crows, and black-billed magpies.

Anatids use their ritualized displays to help keep family groups close, convey information about reproductive status, defend territory or mates, and establish pair bonds. They communicate via sounds as well, with whistles, quacks, and honks. They spend a great deal of time in the water, preening themselves. Anatids use their bills to waterproof their feathers with oil secreted from a gland near their eyes. Waterfowl are social and live in flocks of up to several hundred thousand birds.

Although most anatids are monogamous (muh-NAH-guh-mus; have only one mate), some have several mating partners each season. Those species that are monogamous stay paired for one season, several seasons, or even for life. Breeding season varies depending on region. Courtship displays include vocalization as well as specific swimming patterns and movements. Almost all anatids mate on the water. Nests are then built on land in areas with dense vegetation. Nests are often lined with feathers. Usually the female builds the nest while the male defends her and their territory.

MAKE WAY FOR DUCKLINGS

In May 2004, a mallard duck hatched thirteen ducklings in the courtyard of Christopher Farms Elementary School in Virginia. Prior to their hatching, school officials were not even aware of the nest.

According to an article written by journalist Mary Reid Barrow and printed in The Virginian Pilot, the mother was able to fly in and out but the babies were stuck inside the courtyard in the center of the school. Teachers and others got behind the mother, who repeatedly circled with her ducklings in front of the main doors, and edged all fourteen ducks through the school via the main hallway and out the door.

The family went straight for a nearby pond without another problem.

Eggs are laid over a twenty-four-hour period, and average clutch sizes range from four to thirteen eggs. Incubation (warming sufficiently for hatching) lasts from twenty-two to forty days and is done by the female. With a few species exceptions, males also don't help care for their young. Some anatid species lay their eggs in other females' nests. Within hours of hatching, chicks follow their mother on food outings and are often accompanied by their father, who protects his brood from predators. Chicks stay with mothers for five to ten weeks and are ready to mate around the age of one to three years.

DUCKS, GEESE, SWANS, AND PEOPLE

Anatids and humans have a long history of interaction. Humans have domesticated (tamed) a number of species and have hunted waterfowl almost since the beginning of humankind. Waterfowl hunting is a huge source of revenue in the United States, with outdoor stores selling millions of dollars worth of hunting gear. Also, waterfowl play an important role in keeping the balance of wetland ecosystems.

CONSERVATION STATUS

Six species are Extinct, died out. Four are Critically Endangered, facing an extremely high risk of extinction; nine are Endangered, facing a very high risk of extinction; and twelve species are listed as Vulnerable, facing a high risk of extinction. The greatest threats to these birds are overhunting and wetland drainage. When wetlands are drained, waterfowl can no longer breed there. Pollution from industry also threatens birds in rivers and streams.

MUTE SWAN (Cygnus olor): SPECIES ACCOUNTS

Physical characteristics: This large, white bird weighs anywhere from 14.6 to 33 pounds (6.6 to 15 kilograms) and measures 4 to 5.3 feet (1.3 to 1.6 meters) in length. Its neck is S-shaped, and the bill is orange with a black base. Wingspan measures 7 to 8 feet (2.1 to 2.4 meters). Males and females look alike except males are larger.

Geographic range: Found in central and northern Europe. The mute swan winters in northern Africa, the Near East, and to northwest India and Korea. It has been introduced into the United States.

Habitat: Mute swans require water with plenty of vegetation, such as lagoons, marshes, lakes, and canals.

Diet: Mute swans eat aquatic vegetation, including grass and seeds. They also feed on invertebrates, insects, aquatic worms, and small amphibians. Mute swans do not dive but reach under the water with their long necks and grab food.

Behavior and reproduction: Mute swans get their name for their silence. Only when they're mad will they hiss. This bird is territorial and will fight to the death to defend its home range, which can encompass up to 10 acres (4 hectares). Unlike most anatids, mute swans do not migrate in large flocks. Mute swans fly at a rate of 50 to 55 miles per hour (80.5 to 88.5 kilometers per hour).

Mute swans do not mate for life, but do usually maintain a pair bond for one breeding season. These birds build their large nests in March and April, and the nests are made of vegetation lined with feathers and down. Nests are built in the reeds surrounding water or on floating mats. Clutch size is usually five to seven eggs, sometimes as large as twelve. Incubation lasts thirty-six to thirty-eight days. Chicks (also called cygnets; SIG-nuts) are born with grayish-brown feathers that will turn white within twelve months. The tiny birds stay in the nest only for about an hour. Cygnets ride under parents' wings or on their backs. By the next mating season, parents chase away their young. Mute swans don't usually breed before the age of three years. They oldest known mute swan in the wild was nineteen years.

Mute swans and people: Mute swans have been known to knock down jet-skiiers, and they can be dangerous to small children. They will attack people who get too close to their nests. These birds were saved from extinction due to hunting in Britain when people began domesticating them. The mute swan is the most common swan and is often seen in parks. It is a symbol of love and purity.

Conservation status: Not threatened. In fact, the population of this swan is on the rise. ∎

CANADA GOOSE (Branta canadensis): SPECIES ACCOUNTS

Physical characteristics: This is a large goose with a solid black neck. The head is also black, but there is a white band running underneath the chin. The Canada goose weighs 4.5 to 14.4 pounds (2 to 6.5 kilograms) and stands 21.7 to 43.3 inches (55 to 110 centimeters) tall. Its bill is black, as are its feet. The plumage (feathers) is various shades of brown. Adults lose their feathers and become flightless for three to four weeks each summer until their feathers regrow.

Geographic range: Found in most of Canada and in the United States.

Habitat: The Canada goose feeds in grassland and open marshes. Like other waterfowl, it requires a permanent body of water in which to live.

Diet: Canada geese eat a variety of grasses by pulling them from the ground with their bills. They also feed on corn, wheat, and rice. The mostly herbivorous, eating plant material, bird also eats aquatic vegetation.

Behavior and reproduction: Canada geese migrate slowly in a V-shaped formation, and you know they're above by their loud honking. Each formation is comprised of a number of smaller family groups, and if you watch them land, you'll see the families break off into their individual units. This species can be aggressive and will attack if threatened. These geese are vocal, and pairs will "talk" with one another so quickly that it sounds as if all the sound is coming from just one bird. Babies have a particular raspy call they use to summon their parents.

Canada geese mate for life. They build their nests from grasses and other available vegetation and line them with cattail down. Nests are usually near water. Females lay four to seven eggs and incubate them for twenty-five to thirty days. Within one day of hatching, goslings are led to water by their mother. Canada geese parents often gather goslings into groups and look after them communally. Goslings fly for the first time between forty and eighty-six days, and are ready to mate between two and three years. The average lifespan in the wild is fifteen to twenty years.

A group of flying geese is called a gaggle. A group of geese on the ground is called a skein (skayn).

Canada geese and people: More than most anatids, this species is tolerant of humans. While this has endeared the bird to some, it has been a source of irritation for others. Canada geese like to live in habitats such as golf courses, and their presence is of concern to country clubs and the like. Some humans enjoy feeding these geese, while others prefer hunting them.

Conservation status: Canada geese are not threatened. ∎

MALLARD (Anas platyrhynchos): SPECIES ACCOUNTS

Physical characteristics: Mallards weigh between 1.7 and 3.5 pounds (750 to 1,580 grams) and measure 19.7 to 25.6 inches (50 to 65 centimeters) long. The head of the male is metallic green and the chest is brown. Feet are orange.

Geographic range: Without doubt the most abundant duck, there are approximately ten million mallards in North America and millions more in Eurasia, Europe, and Asia.

Habitat: Mallards live in the shallow, calm waters of wetlands, including marshes, bays, and even city ponds. They prefer to have the protection of some vegetative cover.

Diet: Mallards eat fish, amphibians, and invertebrates. They also on plant parts and eat insects and worms. They eat by dipping their heads beneath the water's surface or by upending, but rarely do they dive.

Behavior and reproduction: Mallards are territorial and become very aggressive when their space is intruded upon. A migratory bird, mallards are among the first to return to breeding grounds in the spring.

Males and females search for nesting ground together. The female lays eight to twelve eggs in her ground nest. Incubation lasts twenty-seven to twenty-eight days, during which the male leaves the female to join a new flock. Ducklings fly between the age of fifty and sixty days and are ready to breed at one year. Mallards are seasonally monogamous, have just one mate per season, and have been known to breed with other species.

Mallards are vocal. The male makes soft sounds while the female quacks so loudly that her call can be heard from miles away. Hawks prey on eggs, but adult mallards are preyed upon primarily by human hunters.

Mallards and people: Mallards are popular with humans because of their beautiful coloration and for their abundant numbers. In Canada, 50 percent of all ducks are mallards. This species is highly tolerant of human activity, which is why public parks are popular habitats. People not only hunt adult mallards for their meat, but also harvest their eggs.

Conservation status: Mallards are common, and not threatened. The Hawaiian subspecies are rare. ∎

KING EIDER (Somateria spectabilis): SPECIES ACCOUNTS

Physical characteristics: Weighs 3.3 to 4.4 pounds (1.5 to 2 kilograms) and measures 17 to 25 inches (43 to 63 centimeters) in length. Male has a blue, yellow, and white head. Bill is bright orange and yellow and develops from a "shield" from the top of the face.

Geographic range: King eiders live on the Arctic coasts. They winter off the coast of Iceland, Norway, Kuril and Aleutian Islands, and as far south as California and Long Island (New York).

Habitat: Lives in oceans and other saltwater areas. Breeds on land in Arctic freshwater wetlands.

Diet: King eiders eat mostly mussels, sand dollars, squid and small fish. They dive (sometimes as deep as 150 feet, or 50 meters) and up-end (put their heads under while their back end stays out of the water) to retrieve food. They also eat tundra vegetation.

Behavior and reproduction: Eiders migrate in a straight line. They are seasonally monogamous, and the male leaves the female midway through incubation. Females lay four to five eggs into holes in the ground that have little lining. Incubation lasts twenty-two to twenty-four days. Ducklings are ready to breed at three years.

King eiders and people: This duck is hunted for food and game, and its down is among the highest quality available, used to make pillows and comforters.

Conservation status: The king eider is common throughout its range. ∎

WOOD DUCK (Aix sponsa): SPECIES ACCOUNTS

Physical characteristics: The male is more colorful than the female, with a metallic green crest and crown surrounding his purple face. Throat is white; tail is square. The body of both sexes is various shades of brown. Measures 17 to 20 inches (43 to 51 centimeters) and weighs about 1.3 pounds (0.6 kilograms).

Geographic range: Found in eastern North America from the southern tip of Florida to northern Nova Scotia, west across Quebec and Ontario to the southern tip of Texas.

Habitat: Wood ducks live in woodland streams and pools, river valleys, swamps and marshlands, and lakes.

Diet: Wood ducks feed primarily on aquatic vegetation. They also eat water and land invertebrates as well as berries, nuts, and seeds.

Behavior and reproduction: This duck migrates to Cuba, the Bahamas, and Mexico for the winter. It is territorial and will defend its range, which is about 24 acres (9.7 hectares) per breeding pair. Wood ducks are vocal, especially during migration.

Pairs form in the fall and are seasonally monogamous. The female lays anywhere from six to fifteen eggs in nests that are actually holes in tree trunks or former woodpecker holes. Incubation lasts twenty-eight to thirty-seven days, and the male leaves just a few days before ducklings hatch. Young leave the nest within two days and are ready to mate at one year. Snapping turtles are the primary predators of eggs and ducklings.

Wood ducks and people: Humans overhunted and destroyed habitats of the wood duck almost to extinction in the early 1900s. The hunting season was declared closed in 1918, which allowed for repopulation.

Conservation status: The white-winged wood duck is considered Endangered, and the black-billed wood duck is Vulnerable due to habitat destruction. ∎

FOR MORE INFORMATION

Books:

Burk, Bruce. Waterfowl Studies: Geese and Swans. Vol. 3. Atglen, PA: Schiffer Publishing, 1999.

Hehner, Mike, Chris Dorsey, and Greg Breining. North American Game Birds (Hunting and Fishing Library Series). Chanhassen, MN: Creative Publishing International, 2002.

Shurtleff, Lawton L., and Christopher Savage. The Wood Duck and the Mandarin: The Northern Wood Ducks. Berkeley, CA: University of California Press, 1996.

Sibley, David Allen, Chris Elphik, and John B. Dunning, eds. The Sibley Guide to Bird Life and Behavior. New York: Knopf Publishing Group, 2001.

Periodicals:

Barrow, Mary Reid. "School Helps Duck Family, and Students Get an Education." The Virginian Pilot (May 16, 2004).

Web sites:

"The Birdhouse Network: Wood Duck." Lab of Ornithology. http://birds.cornell.edu/birdhouse/bird_bios/speciesaccounts/wooduc.html (accessed on May 25, 2004).

Canada Goose Conservation Society. http://www.cgcs.demon.co.uk/ (accessed on May 25, 2004).

Howard, L. "Anatidae." Animal Diversity Web. http://animaldiversity.ummz.umich.edu/site/accounts/information/Anatidae.html (accessed May 25, 2004).

"King Eider." Enature. http://www.enature.com/fieldguide/showSpeciesFT.asp?fotogID=548&curPageNum=1&recnum=BD0675 (accessed on May 25, 2004).

"Mute Swan." Tropical Birds of Paradise. http://www.auburnweb.com/paradise/birds/mute_swan.html (accessed on May 25, 2004).

"Nature: Wood Duck." Texas Parks and Wildlife Department. http://www.tpwd.state.tx.us/factsheets/birds/wood_duck/wood_duck.htm (accessed on June 1, 2004).