The Mallard duck is one of the most common waterfowl known in the world with large well-established populations in North America, Asia, Europe, New Zealand, Australia, and even South Africa. It is thought by experts to be the ancestor of most breeds of domestic ducks.

A migratory bird in the northern hemisphere, in summer months the Mallard may be found as far north as Greenland, and in winter months as far south as Central America, but in general is found in larger numbers in the more temperate middle latitudes.

They are best known for the distinctive green head of the male (see image above), while the female (see below) has a less dramatic mottled brown plumage. Ducklings (also see below) are notable for their dark yellow faces with a black band across the eyes.

Archeological and geological evidence suggest the species has been around since early Pleistocene times, about two million years ago, and have been part of human diet in Europe since at least prehistoric times. They are still a popular bird amongst modern hunters.

They are a larger bird, commonly weighing in at one kilogram (2.2 pounds), about 60 cm (two feet) long, with a wingspan of about 90 cm (three feet). The commonly known duck "quack" is made by the female, while the male's vocalizations are less dramatic.

Usually Mallards may be found living in most wetlands, ponds, and smaller rivers. They are always crowd-pleasers in parks and conservation areas. Diet usually consists of grazing on land or bobbing in the water for food from plants.

Mating is in the spring, and the males only stay with the female until she lays the eggs, at which point he wanders off. Nesting is most commonly on a river bank, but surprisingly for a water bird, not always in the immediate vicinity of water.

Ten to twelve eggs are common for a nest, and they are incubated to hatching in a month, with the ducklings ready to be out on their own in another two months. Later in the summer and during migration, Mallards form large flocks.

With Mallards being so wide-ranging, they tend to cross breed with whatever local species of duck they run into, making for a diversity of hybreds found around the world. In some cases, this may threaten the genetic singularity of the local species.