Male and female Mallard Ducks (Anas platyrhynchos) swimming at the Racine Zoo in Racine, Wisconsin.
The green head and yellow bill of the mallard duck is a familiar sight to many people living in the Northern hemisphere. In fact, the mallard is thought to be the most abundant and wide-ranging duck on Earth.
Mallards prefer calm, shallow sanctuaries, but can be found in almost any body of freshwater across Asia, Europe, and North America. They’re also found in saltwater and brackish water and are commonly found in wetlands.
The male, or drake, is the more distinctively colored of the mallards. Its iconic green head sits atop a white neckband that sets off a chestnut-colored chest and gray body. Females are mottled drab brown in color, but sport iridescent purple-blue wing feathers that are visible as a patch on their sides. They grow to about 26 inches (65 centimeters) in length and can weigh up to 3 pounds (1.4 kilograms).
Mallard groups can often be seen head dipping or completely upending in the water. They rarely dive though, spending their time near the surface and dabbling for invertebrates, fish, amphibians, and a variety of plants. They also graze on land, feeding on grains and plants.
Mated pairs migrate to and breed in the northern parts of their range and build nests on the ground or in a protected cavity. They normally lay about a dozen eggs, and the incubation period lasts just under a month. Mallards are territorial during much of this period, but once incubation is well underway, males abandon the nest and join a flock of other males.
Most mallard species are common and not considered threatened. However one threat to their populations includes hybridization with other ducks.
(Source: National Geographic http://animals.nationalgeographic.com/animals/birds/mallard-duck.html)
This page updated or reviewed in March 2011