The Mallard (Anas platyrhynchos) is a common and widespread duck species found in North America, Europe, Asia, and Australia. It is a medium-sized duck, with a length ranging from 20 to 28 inches and a wingspan of 32 to 39 inches. Adult males, also known as drakes, weigh between 1.9 and 3.5 pounds, while females, or hens, weigh between 1.6 and 2.8 pounds. The Mallard’s body is plump, with a long and broad bill and a rounded head.

One of the distinguishing field marks of the male Mallard is its vibrant green head, which contrasts with a white neck ring and a chestnut-brown breast. The rest of the body is grayish-brown with black and white markings on the wings. In contrast, the female Mallard has a mottled brownish-orange body, with a darker head and bill. Both sexes have a blue patch on their wings, which is visible in flight.

Mallards are migratory birds, with populations in North America and Europe flying south to warmer regions in the fall and returning north in the spring. In North America, Mallards breed across the continent, from Alaska and Canada to northern Mexico. Some populations also breed in Greenland and Iceland. During the winter, Mallards can be found in a variety of wetland habitats, such as ponds, lakes, and marshes.

Mallards are opportunistic feeders and will eat a variety of foods, including seeds, nuts, insects, and aquatic vegetation. They are also known to forage in agricultural fields for grain crops. In urban areas, Mallards can often be seen in parks, ponds, and rivers, where they are fed by humans.

In conclusion, the Mallard is a medium-sized duck species with a plump body, long and broad bill, and distinctive field marks. The male Mallard is easily recognizable by its vibrant green head, white neck ring, and chestnut-brown breast, while the female has a mottled brownish-orange body. Mallards are migratory birds that breed across North America and Europe and winter in wetland habitats. They are opportunistic feeders that will eat a variety of foods, including seeds, nuts, insects, and agricultural crops.