In considering the Northern Shoveler, a common but underappreciated duck, the obvious starting point is not its brilliant plumage, nor even its fascinating and unusual social behavior, but rather its most prominent and highly specialized adaptation--its prodigious and uniquely-equipped bill.

Northern Shovelers have strikingly elongated bills, broader toward the tip, with comblike projections along the lateral edges. Shovelers' bills are adapted for their preferred mode of feeding--swimming along with bill lowered into the water, straining out small crustaceans and other invertebrates. Northern Shovelers are dabbling ducks (genus Anas), but unlike some other dabblers, including Mallards and Northern Pintails, shovelers do not commonly tip their heads and upper bodies forward into the water.

The preferred breeding habitat of the species is open, shallow wetlands. In western North America, the species' breeding range extends from northern Alaska southward and eastward through Saskatchewan, Alberta, Manitoba, North Dakota, and Montana, to its southern limits in the Central Valley of California, northern Nevada, south-central Utah, and northern New Mexico. Its eastern breeding range is more limited; it breeds in portions of southeastern Wisconsin, Michigan, southeast Ontario, southern Quebec, and very locally in other areas.

Males leave their breeding grounds in late August or early September, weeks earlier than females and young. Northern Shovelers winter in various wetland habitats, including both freshwater and saline marshes, throughout much of the southern and southwestern United States and Mexico. Most individuals winter in California, the Gulf Coast of Louisiana and Texas, and inland marshes in Mexico; some wintering shovelers may be found as far north as extreme southern British Columbia and as far south as the Pacific coast of Costa Rica.

The breeding range of the species also spans from northern and central Europe, east through Siberia to the Pacific Coast, and as far south as the Crimea and the Caucasus Mountains. Eurasian Northern Shovelers winter in southern Europe, parts of Egypt and sub-Saharan Africa, eastward through the Middle East across India and southeast Asia to southern China, Japan, and the Philippines.

Northern Shovelers form pairs on their wintering grounds, generally in December. Males exhibit elaborate courtship behavior, including various calls, turns, dips, and wing flaps. Northern Shovelers are monogamous, and remain paired longer than other dabbler species. Males behave territorially during the breeding season, defending their home ranges and mates from other male shovelers.

Females lay 8 to 12 eggs starting in mid-May. The nest is a simple scrape lined with down and usually surrounded on at least three sides by vegetation. New shoveler hatchlings are feathered, and can walk and swim. They leave the nest shortly after hatching. Only female shovelers care for the young.

Northern Shovelers issue a variety of vocalizations. Females utter short series of loud single quacks with even pauses at dusk from February throughout the mating season. They exhibit slightly different quacking patterns immediately before egg-laying, and when they are flushed from the nest. In courtship and copulation, males emit nasal "took" notes; in fall and early winter, males frequently issue a nasal "paaay." Northern Shovelers also make a rattling noise, unique among dabbling ducks, when they take flight.

Description:
Northern Shovelers are of medium size relative to other dabbling ducks. Adult males measure about 50 cm from bill tip to tail; females are about 10 percent smaller. For both sexes, the long bill is the species' most distinguishing feature. Both male and female Northern Shovelers also have light-blue patches on their upper-wing coverts; such blue markings are also characteristic of Cinnamon and Blue-winged teal, as well as two other shoveler species.

Breeding males have iridescent, dark green heads, black bills, and yellow eyes. (Male Mallards also have shiny green heads, but their eyes are dark and their bills yellow--and modestly proportioned.) The breasts of breeding male shovelers are pure white, and their flanks rufous. They show these bright colors from December to May, whereupon they molt into plainer plumage, with a dark-brown or blackish head, dusky eye line, dark brown breast and belly, and light brown flanks. The bills of nonbreeding adult males are orange at the base and along the edges, and black on most of the upper mandible.

Females and immature males are mostly brown and gray; the edges of their body feathers are pale, giving their plumage a highly textured appearance. Their bills resemble those of nonbreeding adult males.